A study published in PLoS ONE today addresses the impact of neuroprotection on Alzheimer's disease. Remarkably, the study shows that even very modest neuroprotective effects at the cellular level can lead to dramatic reductions in the number of cases of Alzheimer's. Based on data derived from 26 epidemiological studies worldwide (comprising over 60,000 subjects), Dr de la Fuente-Fernandez developed a simple mathematical model that will allow researchers to test the effect of new neuroprotective drugs. Perhaps not too surprisingly, the study suggests however that the most effective neuroprotective therapy for Alzheimer's disease may well not be a pill, but education and intellectual activity. Mounting evidence accumulated over the last few ye ars supports the notion that intellectual activity increases what neuroscientists call "the cognitive reserve". According to the model, a mere 5% increase in the cognitive reserve in the general population would prevent one third of Alzheimer's cases. Dr de la Fuente-Fernandez, a neurologist at the Hospital A. Marcide in Ferrol (Spain), points out that public health policies aimed at implementing higher levels of education in the general population are likely the best strategy for preventing Alzheimer's disease.
Citation: de la Fuente-Fernández R (2006) Impact of Neuroprotection on Incidence of Alzheimer's Disease. PLoS ONE 1(1): e52. doi:10.1371/journal.pone.0000052
http://dx.doi.org/10.1371/journal.pone.0000052
Thursday, December 21, 2006
Antenatal fish oil supplements boost kids' hand-eye coordination
Fish oil supplements given to pregnant mums boost the hand-eye coordination of their babies as toddlers, reveals a small study published ahead of print in the Archives of Disease in Childhood (Fetal and Neonatal Edition).
The researchers base their findings on 98 pregnant women, who were either given 4g of fish oil supplements or 4g of olive oil supplements daily from 20 weeks of pregnancy until the birth of their babies.
Only non-smokers and those who did not routinely eat more than two weekly portions of fish were included in the study. Eighty three mothers completed the study.
Once the children had reached two and a half years of age, they were assessed using validated tests to measure growth and development.
These included tests of language, behaviour, practical reasoning and hand-eye coordination. In all, 72 children were assessed (33 in the fish oil group and 39 in the olive oil group).
There were no significant overall differences in language skills and growth between the two groups of children
But those whose mothers had taken fish oil supplements scored more highly on measures of receptive language (comprehension), average phrase length, and vocabulary.
And children whose mothers had taken fish oil supplements scored significantly higher in hand-eye coordination than those whose mothers had taken the olive oil supplements.
This finding held true even after taking into account other potentially influential factors, such as the mother's age and duration of breast feeding.
High cord blood levels of omega 3 fatty acids at birth (from fish oil) were strongly associated with good hand-eye coordination, while low levels of omega 6 fatty acids, found in many vegetable oils, were not.
Prompted by concerns about mercury content in certain types of fish, pharmaceutical grade fish oil supplements are becoming increasingly popular, say the authors.
The findings show that relatively high doses of omega 3 rich fish oil supplements in the second half of pregnancy do not seem to have any adverse effects on neurodevelopment or growth, they add.
The researchers base their findings on 98 pregnant women, who were either given 4g of fish oil supplements or 4g of olive oil supplements daily from 20 weeks of pregnancy until the birth of their babies.
Only non-smokers and those who did not routinely eat more than two weekly portions of fish were included in the study. Eighty three mothers completed the study.
Once the children had reached two and a half years of age, they were assessed using validated tests to measure growth and development.
These included tests of language, behaviour, practical reasoning and hand-eye coordination. In all, 72 children were assessed (33 in the fish oil group and 39 in the olive oil group).
There were no significant overall differences in language skills and growth between the two groups of children
But those whose mothers had taken fish oil supplements scored more highly on measures of receptive language (comprehension), average phrase length, and vocabulary.
And children whose mothers had taken fish oil supplements scored significantly higher in hand-eye coordination than those whose mothers had taken the olive oil supplements.
This finding held true even after taking into account other potentially influential factors, such as the mother's age and duration of breast feeding.
High cord blood levels of omega 3 fatty acids at birth (from fish oil) were strongly associated with good hand-eye coordination, while low levels of omega 6 fatty acids, found in many vegetable oils, were not.
Prompted by concerns about mercury content in certain types of fish, pharmaceutical grade fish oil supplements are becoming increasingly popular, say the authors.
The findings show that relatively high doses of omega 3 rich fish oil supplements in the second half of pregnancy do not seem to have any adverse effects on neurodevelopment or growth, they add.
Kidney Stones Occurring More Often in Children
Diet, Proper Hydration Keys to Prevention, Children's Center Doctors Say
Kidney stones in children - considered all but a medical aberration until recently - are now becoming a fairly common condition. It's a growing and disturbing trend that has pediatricians at the Johns Hopkins Children's Center, and around the country, sounding the alarm.
While doctors have yet to quantify the precise increase and tease out the factors behind it - better detection devices probably play some role - pediatricians agree that too much salt and too little drinking water in children's diets are probably the main culprits.
"More and more children with kidney stones are coming to us," says kidney specialist Alicia Neu, M.D., co-director of the kidney stone clinic at the Children's Center. "While this is somewhat unexpected, it is not totally surprising given that so many other conditions are on the rise in children due to poor diet, such as high blood pressure, type 2 diabetes and obesity to name a few."
Kidney stones are rarely a serious condition, but can be extremely painful and can cause urinary tract infections.
Limiting salt in the diet and drinking plenty of water are the best ways to prevent the most common types of kidney stones or slow their growth. Here are several simple tips to keep in mind:
- Doctors recommend consuming no more than 2.4 grams of sodium a day, or 6 grams (1 teaspoon) of table salt a day.
- Stay away from salty snacks, such as chips and pretzels, which are loaded with sodium.
- Processed foods, including smoked and cured meats, as well as sodas and canned products have the highest sodium content.
- Look for "no salt added" or "low sodium" labels when buying food.
- Rinse canned foods under water to remove some of the sodium.
- Tea, coffee, dark chocolate, spinach, nuts and wheat bran can also increase the risk of certain types of kidney stones.
- A child needs to drink two liters (64 ounces) of water a day.
- Sugar-laden juices and sodas don't count as proper hydration.
"Clearly, when it comes to water consumption, what is needed is a cultural change, and schools have to play a role in making bottled water available and limiting soft drinks, as well as allowing children to visit the restroom as needed," says urologist Yegappan Lakshmanan, M. D., co-director of the Center's pediatric stone clinic.
A good way for a child to tell if he or she is drinking enough water is the urge to urinate every three hours. If a child urinates less frequently than that, it might be a sign of dehydration, Lakshmanan says.
Signs and symptoms of kidney stones include:
- Intense pain in the lower-back and/or in the sides
- Frequent and painful urination
- Blood in the urine and/or cloudy urine
- Urinary tract infections, secondary to kidney stones, accompanied by fever
Kidney stones in children - considered all but a medical aberration until recently - are now becoming a fairly common condition. It's a growing and disturbing trend that has pediatricians at the Johns Hopkins Children's Center, and around the country, sounding the alarm.
While doctors have yet to quantify the precise increase and tease out the factors behind it - better detection devices probably play some role - pediatricians agree that too much salt and too little drinking water in children's diets are probably the main culprits.
"More and more children with kidney stones are coming to us," says kidney specialist Alicia Neu, M.D., co-director of the kidney stone clinic at the Children's Center. "While this is somewhat unexpected, it is not totally surprising given that so many other conditions are on the rise in children due to poor diet, such as high blood pressure, type 2 diabetes and obesity to name a few."
Kidney stones are rarely a serious condition, but can be extremely painful and can cause urinary tract infections.
Limiting salt in the diet and drinking plenty of water are the best ways to prevent the most common types of kidney stones or slow their growth. Here are several simple tips to keep in mind:
- Doctors recommend consuming no more than 2.4 grams of sodium a day, or 6 grams (1 teaspoon) of table salt a day.
- Stay away from salty snacks, such as chips and pretzels, which are loaded with sodium.
- Processed foods, including smoked and cured meats, as well as sodas and canned products have the highest sodium content.
- Look for "no salt added" or "low sodium" labels when buying food.
- Rinse canned foods under water to remove some of the sodium.
- Tea, coffee, dark chocolate, spinach, nuts and wheat bran can also increase the risk of certain types of kidney stones.
- A child needs to drink two liters (64 ounces) of water a day.
- Sugar-laden juices and sodas don't count as proper hydration.
"Clearly, when it comes to water consumption, what is needed is a cultural change, and schools have to play a role in making bottled water available and limiting soft drinks, as well as allowing children to visit the restroom as needed," says urologist Yegappan Lakshmanan, M. D., co-director of the Center's pediatric stone clinic.
A good way for a child to tell if he or she is drinking enough water is the urge to urinate every three hours. If a child urinates less frequently than that, it might be a sign of dehydration, Lakshmanan says.
Signs and symptoms of kidney stones include:
- Intense pain in the lower-back and/or in the sides
- Frequent and painful urination
- Blood in the urine and/or cloudy urine
- Urinary tract infections, secondary to kidney stones, accompanied by fever
Wednesday, December 20, 2006
Sippy Cups Linked to Cavities
The Center for Disease Control and Prevention compared the dental health of Americans from two periods: 1988-1994 and 1999-2002. The result: a 15.2 percent increase in cavities among 2- to 5-year-olds. More research shows that nearly one-third of toddlers with tooth decay used sippy cups. Thus, a few tips from the American Academy of Pediatric Dentistry:
• The sippy cup should not be used for long periods of time.
• Unless being used at mealtime, it should be filled only with water.
• Sippy cups should not be used at nap time or bedtime unless they have only water in them.
• Schedule regular visits with a pediatric dentist to help keep your child cavity-free.
• The sippy cup should not be used for long periods of time.
• Unless being used at mealtime, it should be filled only with water.
• Sippy cups should not be used at nap time or bedtime unless they have only water in them.
• Schedule regular visits with a pediatric dentist to help keep your child cavity-free.
Monday, December 18, 2006
Some alcohol protects against death from head injury
Patients who have low to moderate blood alcohol levels may be less likely to die after arriving at the hospital with a traumatic brain injury than those with no alcohol in their bloodstream, according to a report in the December issue of Archives of Surgery, one of the JAMA/Archives journals. However, those with the highest alcohol levels appear to have an increased risk of dying in the hospital.
Alcohol use is a major risk factor for trauma, according to background information in the article. About one-third to one-half of all patients hospitalized with trauma are intoxicated at the time of injury. However, the effect of alcohol on how patients fare after a traumatic brain injury—a leading cause of disability and death among young people—is unclear. Some human and animal studies suggest that alcohol may be neuroprotective, keeping the injury from worsening once it has occurred.
Homer C. N. Tien, M.D., F.R.C.S.C., Sunnybrook Health Sciences Centre, University of Toronto, and colleagues studied 1,158 consecutive patients who were evaluated at an academic level I trauma center for severe brain injury caused by blunt trauma between 1988 and 2003. Tests done when the patients were admitted determined blood alcohol concentration (BAC). This information, as well as data on demographics, type of injury, severity of the injury, length of hospital stay and whether the patient died or left the hospital, was gathered from the hospital’s trauma registry. The researchers also assessed a group of 528 patients with severe torso injuries, but no or mild head injuries, as a comparison.
Of the 1,158 traumatic brain injury patients, 740 had a BAC of zero, 315 had low to moderate BAC (0 to 230 milligrams per deciliter) and 103 had high BAC (230 milligrams per deciliter or higher); 403 died in the hospital. Those with a low to moderate BAC were less likely to die than those with no BAC (27.9 percent died vs. 36.3 percent). After adjusting for other factors that could influence the risk of death—including injury severity, blood transfusions and whether the trauma occurred in a motor vehicle crash—BAC was still associated with the risk of death. Those with a low to moderate BAC had 24 percent lower odds of dying in the hospital than those with no BAC. In contrast, those with a high BAC had 73 percent higher odds of dying than those with no BAC. Among patients with torso injuries, BAC was not related to the risk of death.
The authors mention that low to moderate doses of alcohol may protect the brain by stopping the mechanisms that contribute to secondary brain injury, which occurs when traumatized brain cells continue to be deprived of oxygen and worsens the damage caused by the initial event.
"There are major sociologic implications from implying that intoxicated patients with severe traumatic brain injury have better outcomes than non-intoxicated patients," the authors write. "We stress that our study only examined the role of alcohol on outcome in the post-injury phase because we examined only in-hospital deaths." About half of all individuals who die from trauma do so before they arrive at the hospital, they continue. Because alcohol use increases the likelihood of a severe injury, alcohol-related deaths comprise a large percentage of those who die before they have a chance to get to the hospital.
"Overall, people are still at much greater risk of dying if they drive while intoxicated," the authors conclude. "What our study implies is that there may be a role for an alcohol-based resuscitation fluid in improving outcomes in adequately resuscitated patients with severe head injury."
Alcohol use is a major risk factor for trauma, according to background information in the article. About one-third to one-half of all patients hospitalized with trauma are intoxicated at the time of injury. However, the effect of alcohol on how patients fare after a traumatic brain injury—a leading cause of disability and death among young people—is unclear. Some human and animal studies suggest that alcohol may be neuroprotective, keeping the injury from worsening once it has occurred.
Homer C. N. Tien, M.D., F.R.C.S.C., Sunnybrook Health Sciences Centre, University of Toronto, and colleagues studied 1,158 consecutive patients who were evaluated at an academic level I trauma center for severe brain injury caused by blunt trauma between 1988 and 2003. Tests done when the patients were admitted determined blood alcohol concentration (BAC). This information, as well as data on demographics, type of injury, severity of the injury, length of hospital stay and whether the patient died or left the hospital, was gathered from the hospital’s trauma registry. The researchers also assessed a group of 528 patients with severe torso injuries, but no or mild head injuries, as a comparison.
Of the 1,158 traumatic brain injury patients, 740 had a BAC of zero, 315 had low to moderate BAC (0 to 230 milligrams per deciliter) and 103 had high BAC (230 milligrams per deciliter or higher); 403 died in the hospital. Those with a low to moderate BAC were less likely to die than those with no BAC (27.9 percent died vs. 36.3 percent). After adjusting for other factors that could influence the risk of death—including injury severity, blood transfusions and whether the trauma occurred in a motor vehicle crash—BAC was still associated with the risk of death. Those with a low to moderate BAC had 24 percent lower odds of dying in the hospital than those with no BAC. In contrast, those with a high BAC had 73 percent higher odds of dying than those with no BAC. Among patients with torso injuries, BAC was not related to the risk of death.
The authors mention that low to moderate doses of alcohol may protect the brain by stopping the mechanisms that contribute to secondary brain injury, which occurs when traumatized brain cells continue to be deprived of oxygen and worsens the damage caused by the initial event.
"There are major sociologic implications from implying that intoxicated patients with severe traumatic brain injury have better outcomes than non-intoxicated patients," the authors write. "We stress that our study only examined the role of alcohol on outcome in the post-injury phase because we examined only in-hospital deaths." About half of all individuals who die from trauma do so before they arrive at the hospital, they continue. Because alcohol use increases the likelihood of a severe injury, alcohol-related deaths comprise a large percentage of those who die before they have a chance to get to the hospital.
"Overall, people are still at much greater risk of dying if they drive while intoxicated," the authors conclude. "What our study implies is that there may be a role for an alcohol-based resuscitation fluid in improving outcomes in adequately resuscitated patients with severe head injury."
Fewer sugary drinks during childhood may cut disease risk
Symptoms of heart disease and diabetes usually seen in adults are increasingly being found in adolescents according to a longitudinal study, which suggests that reducing the intake of sugar-sweetened beverages during childhood may lessen the risk of chronic disease in later life.
"Research on obesity and associated problems such as hypertension and type-2 diabetes has largely dealt with adults," says Alison Ventura, doctoral candidate at Penn State's Center for Childhood Obesity Research. "But with increasing rates of obesity in children, we are seeing these problems at much younger ages."
Ventura and her colleagues Eric Loken, assistant professor of human development and family studies, and Leann Birch, professor of human development and family studies, are studying the clustering of traits such as insulin resistance, abdominal obesity, hypertension, and high triglycerides combined with low HDL – good cholesterol – that are thought to be related to cardiovascular disease and diabetes in adults.
The clustering of these traits, otherwise known as metabolic syndrome, is a strong indicator for chronic disease, and is being diagnosed in an increasing number of U.S adults and adolescents.
"Researchers think insulin resistance is the underlying trait that leads to the other metabolic abnormalities," says Ventura. "It is now thought that obesity may be a trigger for insulin resistance, thus creating a cascade of risk."
However, the Penn State researcher adds there is little data on the prevalence of metabolic syndrome in children since they are not routinely screened. Her team is trying to find a risk profile for later disease among children having the symptoms for metabolic syndrome.
The current study, funded by the National Institutes of Health, looked at different traits such as blood pressure, waist circumference, and levels of HDL cholesterol, triglycerides, and glucose in 154 white non-Hispanic 13-year-old girls and their parents, from central Pennsylvania. This study also had data on the girls and their parents' dietary, activity and lifestyle patterns starting from when the girls were five-years-old.
"We first looked for different profiles for the indicators of metabolic syndrome when the girls were 13, then worked backwards to see what was causing them in the first place," says Ventura, whose findings appear this month (December) in the Journal of American Academy of Pediatrics.
The study found statistical support was the greatest for the presence of four different groups within the sample: These groups included girls with higher blood pressure and waist circumference values; girls with higher levels of triglycerides and lower levels of HDL cholesterol; girls with more desirable values on all of the metabolic syndrome indicators, and girls with more undesirable values on all of the indicators.
"We wanted to see if we could find higher and lower risk profiles in the sample," explains Ventura. "Next we wanted to see if there were certain characteristics across ages 5 to 11 that predicted having a higher or lower risk profile."
Results from the study further suggest that girls within the risk groups for hypertension and metabolic syndrome also had significantly greater increases in weight and fat mass between the ages of 5 and 13 compared to the other two groups. Those at higher risk for metabolic syndrome were also found to be consuming significantly more servings of sugary beverages between the ages of 5 and 9 compared to the other three groups.
The Penn State researcher , however, cautions on making general interpretations from the study.
"We do not have future data on these girls and so we can only speculate that girls in the high risk group might develop metabolic syndrome, heart disease or type-2 diabetes," she adds.
Though the study cannot definitely pinpoint which children will develop chronic diseases, Ventura says the results show evidence for metabolic syndrome in early adolescence. They also illustrate several possible disease trajectories that may be avoided by certain measures during early childhood. The researchers also point out that only girls were included in the study.
"Family history does play a role, but it appears that we can prevent the development of metabolic syndrome in children by taking certain actions in early life. Controlling weight gain and the intake of sugar-sweetened drinks may prevent a child from the risk of disease later in life," Ventura adds.
###
The Penn State Center for Childhood Obesity Research is at http://www.hhdev.psu.edu/ccor/
"Research on obesity and associated problems such as hypertension and type-2 diabetes has largely dealt with adults," says Alison Ventura, doctoral candidate at Penn State's Center for Childhood Obesity Research. "But with increasing rates of obesity in children, we are seeing these problems at much younger ages."
Ventura and her colleagues Eric Loken, assistant professor of human development and family studies, and Leann Birch, professor of human development and family studies, are studying the clustering of traits such as insulin resistance, abdominal obesity, hypertension, and high triglycerides combined with low HDL – good cholesterol – that are thought to be related to cardiovascular disease and diabetes in adults.
The clustering of these traits, otherwise known as metabolic syndrome, is a strong indicator for chronic disease, and is being diagnosed in an increasing number of U.S adults and adolescents.
"Researchers think insulin resistance is the underlying trait that leads to the other metabolic abnormalities," says Ventura. "It is now thought that obesity may be a trigger for insulin resistance, thus creating a cascade of risk."
However, the Penn State researcher adds there is little data on the prevalence of metabolic syndrome in children since they are not routinely screened. Her team is trying to find a risk profile for later disease among children having the symptoms for metabolic syndrome.
The current study, funded by the National Institutes of Health, looked at different traits such as blood pressure, waist circumference, and levels of HDL cholesterol, triglycerides, and glucose in 154 white non-Hispanic 13-year-old girls and their parents, from central Pennsylvania. This study also had data on the girls and their parents' dietary, activity and lifestyle patterns starting from when the girls were five-years-old.
"We first looked for different profiles for the indicators of metabolic syndrome when the girls were 13, then worked backwards to see what was causing them in the first place," says Ventura, whose findings appear this month (December) in the Journal of American Academy of Pediatrics.
The study found statistical support was the greatest for the presence of four different groups within the sample: These groups included girls with higher blood pressure and waist circumference values; girls with higher levels of triglycerides and lower levels of HDL cholesterol; girls with more desirable values on all of the metabolic syndrome indicators, and girls with more undesirable values on all of the indicators.
"We wanted to see if we could find higher and lower risk profiles in the sample," explains Ventura. "Next we wanted to see if there were certain characteristics across ages 5 to 11 that predicted having a higher or lower risk profile."
Results from the study further suggest that girls within the risk groups for hypertension and metabolic syndrome also had significantly greater increases in weight and fat mass between the ages of 5 and 13 compared to the other two groups. Those at higher risk for metabolic syndrome were also found to be consuming significantly more servings of sugary beverages between the ages of 5 and 9 compared to the other three groups.
The Penn State researcher , however, cautions on making general interpretations from the study.
"We do not have future data on these girls and so we can only speculate that girls in the high risk group might develop metabolic syndrome, heart disease or type-2 diabetes," she adds.
Though the study cannot definitely pinpoint which children will develop chronic diseases, Ventura says the results show evidence for metabolic syndrome in early adolescence. They also illustrate several possible disease trajectories that may be avoided by certain measures during early childhood. The researchers also point out that only girls were included in the study.
"Family history does play a role, but it appears that we can prevent the development of metabolic syndrome in children by taking certain actions in early life. Controlling weight gain and the intake of sugar-sweetened drinks may prevent a child from the risk of disease later in life," Ventura adds.
###
The Penn State Center for Childhood Obesity Research is at http://www.hhdev.psu.edu/ccor/
New Dyslexia Theory Blames 'Noise'
Poor filtering of unwanted data may be the root cause of common disorder
The National Institute of Child Health and Human Development defines dyslexia as "a specific learning disability that is neurobiological in origin. It is characterized by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities. These difficulties typically result from a deficit in the phonological component of language that is often unexpected in relation to other cognitive abilities and the provision of effective classroom instruction.
Secondary consequences may include problems in reading comprehension and reduced reading experience that can impede growth of vocabulary and background knowledge."
The dyslexic brain struggles to read because even small distractions can throw it off, according to a new model of dyslexia emerging from a group of recent studies.
The studies contradict an influential, 30-year-old theory that blamed dyslexia on a neural deficit in processing the fast sounds of language.
Instead, the studies suggest that children with dyslexia have bad filters for irrelevant data. As a result, they struggle to form solid mental categories for identifying letters and word sounds.
Such children may benefit from intensive training under "noisy" conditions to strengthen their mental templates, said University of Southern California neuroscientist Zhong-Lin Lu.
Lu was a co-author on three studies, along with lead author and former USC graduate student Anne Sperling (now at the National Institute of Mental Health), USC psychologist Franklin Manis and University of Wisconsin, Madison psychologist Mark Seidenberg.
The most recent study is due to be published later this month in Psychological Science.
Confusion about dyslexia rivals the confusion of dyslexia. Many still think that to have dyslexia means to mix up your letters (one of many possible symptoms having to do with word recognition, directional ability and decoding of symbols)
.
What is known is that dyslexia affects millions of children, with estimates of its incidence ranging from 5 to 15 percent.
Sperling, who conducted her research as a doctoral student at USC, said the new findings point to a deeper problem - not just a visual deficit - affecting all areas of perception.
Sperling said people with dyslexia appear to have shaky mental categories for the essential sounds that make up language.
"It's harder to make a [language] task automatic when your categories are fuzzier than they ought to be to begin with," she said.
"In terms of treatment, the results suggest that programs that foster the development of sharper perceptual categories for letters and letter sounds might be a good way to supplement existing dyslexia interventions," she added.
Lu said, "Train them in noise."
The new study in Psychological Science builds on similar results published by the team of Sperling, Lu, Manis and Seidenberg last year in Nature Neuroscience.
In addition, the same authors previously showed that poor readers also have trouble figuring out categories in simple card games.
Other recent studies lend support to the noise exclusion theory.
Johannes Ziegler of the Universite de Provence in Marseille, France, was the lead author on a study of dyslexia and auditory noise published this year in Proceedings of the National Academy of Sciences.
Ziegler said his results suggest that dyslexia stems from shaky categories for phonemes (the basic sounds of language).
"In silence, information is often redundant and dyslexics get away with the perception deficit," Ziegler said in an e-mail. "In noise, however, they can no longer compensate.
"What is important is that noisy environments are the rule and not the exception," he added, citing a study from South Bank University in the U.K. that found average noise levels in primary classrooms to be as high as near a busy intersection.
"What Sperling and Lu's data suggest is that the mechanism responsible for faulty phonological development is quite general and has to do with attention in a broad sense....
"This is a great paper of very high significance... As people like Steve Grossberg [of Boston University] have argued for many years, attention ... is crucial for stable learning of categories."
Ziegler called for preventive training for children with weak speech perception in noise in kindergarten or early primary grades, saying they are at greater risk for developing dyslexia.
He also cited a Northwestern University study from 2003 that documented negative effects from noise on children with learning deficits.
Lu said there is a "lot of evidence" of learning problems from ambient noise. In one such study, Manis and a collaborator from UCLA found that children with dyslexia struggled to discriminate similar sounds, like "spy" and "sky," because they weighed irrelevant differences in sounds equally with key distinctions.
Manis also cited research from Finland and the United States showing that infants with dyslexic parents lag behind their peers in forming categories for speech sounds.
In the conclusion to their study in Psychological Science, the authors speculate that the deficit in noise exclusion may have biochemical roots in abnormal levels of GABA, a neurotransmitter that helps the brain to filter out irrelevant information.
"This may become interesting for drug development," said Lu, who is testing this hypothesis with functional magnetic resonance imaging trials.
Lu and his collaborators interpret the new results as a rejection of the "magnocellular hypothesis" - named for a type of neuron involved in processing fast visual information - that influenced dyslexia research for decades.
The researchers found that the magnocellular pathway works normally both in children with dyslexia and in adult poor readers - as long as visual or aural noise is low.
As external noise goes up, the same subjects begin to score poorly on visual pattern tests.
The deficit persists even when the task requires only slow processing.
"The findings, and particularly the [slow processing] ones, are consistent with the hypothesis that ... dyslexic children have difficulty setting their signal filters to optimum and ignoring distracting noise," Lu said at the time of the Nature Neuroscience study.
The new study in Psychological Science was designed to replicate visual tests on motion perception from seminal experiments in the 1970s, with the addition of variable external noise. It also found no magnocellular deficit.
"These were the stimuli people used to establish the magnocellular hypothesis," Lu said. "This is a more direct test of what we said before [in the Nature Neuroscience study], which used different spatial and temporal patterns."
The National Institute of Child Health and Human Development defines dyslexia as "a specific learning disability that is neurobiological in origin. It is characterized by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities. These difficulties typically result from a deficit in the phonological component of language that is often unexpected in relation to other cognitive abilities and the provision of effective classroom instruction.
Secondary consequences may include problems in reading comprehension and reduced reading experience that can impede growth of vocabulary and background knowledge."
The dyslexic brain struggles to read because even small distractions can throw it off, according to a new model of dyslexia emerging from a group of recent studies.
The studies contradict an influential, 30-year-old theory that blamed dyslexia on a neural deficit in processing the fast sounds of language.
Instead, the studies suggest that children with dyslexia have bad filters for irrelevant data. As a result, they struggle to form solid mental categories for identifying letters and word sounds.
Such children may benefit from intensive training under "noisy" conditions to strengthen their mental templates, said University of Southern California neuroscientist Zhong-Lin Lu.
Lu was a co-author on three studies, along with lead author and former USC graduate student Anne Sperling (now at the National Institute of Mental Health), USC psychologist Franklin Manis and University of Wisconsin, Madison psychologist Mark Seidenberg.
The most recent study is due to be published later this month in Psychological Science.
Confusion about dyslexia rivals the confusion of dyslexia. Many still think that to have dyslexia means to mix up your letters (one of many possible symptoms having to do with word recognition, directional ability and decoding of symbols)
.
What is known is that dyslexia affects millions of children, with estimates of its incidence ranging from 5 to 15 percent.
Sperling, who conducted her research as a doctoral student at USC, said the new findings point to a deeper problem - not just a visual deficit - affecting all areas of perception.
Sperling said people with dyslexia appear to have shaky mental categories for the essential sounds that make up language.
"It's harder to make a [language] task automatic when your categories are fuzzier than they ought to be to begin with," she said.
"In terms of treatment, the results suggest that programs that foster the development of sharper perceptual categories for letters and letter sounds might be a good way to supplement existing dyslexia interventions," she added.
Lu said, "Train them in noise."
The new study in Psychological Science builds on similar results published by the team of Sperling, Lu, Manis and Seidenberg last year in Nature Neuroscience.
In addition, the same authors previously showed that poor readers also have trouble figuring out categories in simple card games.
Other recent studies lend support to the noise exclusion theory.
Johannes Ziegler of the Universite de Provence in Marseille, France, was the lead author on a study of dyslexia and auditory noise published this year in Proceedings of the National Academy of Sciences.
Ziegler said his results suggest that dyslexia stems from shaky categories for phonemes (the basic sounds of language).
"In silence, information is often redundant and dyslexics get away with the perception deficit," Ziegler said in an e-mail. "In noise, however, they can no longer compensate.
"What is important is that noisy environments are the rule and not the exception," he added, citing a study from South Bank University in the U.K. that found average noise levels in primary classrooms to be as high as near a busy intersection.
"What Sperling and Lu's data suggest is that the mechanism responsible for faulty phonological development is quite general and has to do with attention in a broad sense....
"This is a great paper of very high significance... As people like Steve Grossberg [of Boston University] have argued for many years, attention ... is crucial for stable learning of categories."
Ziegler called for preventive training for children with weak speech perception in noise in kindergarten or early primary grades, saying they are at greater risk for developing dyslexia.
He also cited a Northwestern University study from 2003 that documented negative effects from noise on children with learning deficits.
Lu said there is a "lot of evidence" of learning problems from ambient noise. In one such study, Manis and a collaborator from UCLA found that children with dyslexia struggled to discriminate similar sounds, like "spy" and "sky," because they weighed irrelevant differences in sounds equally with key distinctions.
Manis also cited research from Finland and the United States showing that infants with dyslexic parents lag behind their peers in forming categories for speech sounds.
In the conclusion to their study in Psychological Science, the authors speculate that the deficit in noise exclusion may have biochemical roots in abnormal levels of GABA, a neurotransmitter that helps the brain to filter out irrelevant information.
"This may become interesting for drug development," said Lu, who is testing this hypothesis with functional magnetic resonance imaging trials.
Lu and his collaborators interpret the new results as a rejection of the "magnocellular hypothesis" - named for a type of neuron involved in processing fast visual information - that influenced dyslexia research for decades.
The researchers found that the magnocellular pathway works normally both in children with dyslexia and in adult poor readers - as long as visual or aural noise is low.
As external noise goes up, the same subjects begin to score poorly on visual pattern tests.
The deficit persists even when the task requires only slow processing.
"The findings, and particularly the [slow processing] ones, are consistent with the hypothesis that ... dyslexic children have difficulty setting their signal filters to optimum and ignoring distracting noise," Lu said at the time of the Nature Neuroscience study.
The new study in Psychological Science was designed to replicate visual tests on motion perception from seminal experiments in the 1970s, with the addition of variable external noise. It also found no magnocellular deficit.
"These were the stimuli people used to establish the magnocellular hypothesis," Lu said. "This is a more direct test of what we said before [in the Nature Neuroscience study], which used different spatial and temporal patterns."
Saturday, December 16, 2006
Selenium's Health Benefits
Selenium and cancer
Observational studies indicate that death from cancer, including lung, colorectal, and prostate cancers, is lower among people with higher blood levels or intake of selenium . In addition, the incidence of nonmelanoma skin cancer is significantly higher in areas of the United States with low soil selenium content. The effect of selenium supplementation on the recurrence of different types of skin cancers was studied in seven dermatology clinics in the U.S. from 1983 through the early 1990s. Taking a daily supplement containing 200g of selenium did not affect recurrence of skin cancer, but significantly reduced the occurrence and death from total cancers. The incidence of prostate cancer, colorectal cancer, and lung cancer was notably lower in the group given selenium supplements.
Research suggests that selenium affects cancer risk in two ways. As an anti-oxidant, selenium can help protect the body from damaging effects of free radicals. Selenium may also prevent or slow tumor growth. Certain breakdown products of selenium are believed to prevent tumor growth by enhancing immune cell activity and suppressing development of blood vessels to the tumor .
The SELECT study, a long-term study sponsored by the NIH, is investigating whether supplemental selenium and/or vitamin E can decrease the risk of prostate cancer in healthy men. Past evidence as well as pre-clinical trials for the SELECT study suggests that these two nutrients may be effective in preventing prostate cancer. A daily supplement containing 200 g of selenium will be given to individuals in the selenium-only study group, while men in the combined-nutrients group will receive a daily supplement containing 200g selenium and 400 mg vitamin E. The study, which will span from 2001 to 2013, will include 32,400 healthy adult men .
Selenium and heart disease_
Some population surveys have suggested an association between lower antioxidant intake and a greater incidence of heart disease. Evidence also suggests that oxidative stress from free radicals, which are natural by-products of oxygen metabolism, may promote heart disease. For example, it is the oxidized form of low-density lipoproteins (LDL, often called "bad" cholesterol) that promotes plaque build-up in coronary arteries. Selenium is one of a group of antioxidants that may help limit the oxidation of LDL cholesterol and thereby help to prevent coronary artery disease . Currently there is insufficient evidence available to recommend selenium supplements for the prevention of coronary heart disease.
Selenium and arthritis_
Surveys indicate that individuals with rheumatoid arthritis, a chronic disease that causes pain, stiffness, swelling, and loss of function in joints, have reduced selenium levels in their blood. In addition, some individuals with arthritis have a low selenium intake. __The body's immune system naturally makes free radicals that can help destroy invading organisms and damaged tissue, but that can also harm healthy tissue. Selenium, as an antioxidant, may help to relieve symptoms of arthritis by controlling levels of free radicals. Current findings are considered preliminary, and further research is needed before selenium supplements can be recommended for individuals with arthritis.
Observational studies indicate that death from cancer, including lung, colorectal, and prostate cancers, is lower among people with higher blood levels or intake of selenium . In addition, the incidence of nonmelanoma skin cancer is significantly higher in areas of the United States with low soil selenium content. The effect of selenium supplementation on the recurrence of different types of skin cancers was studied in seven dermatology clinics in the U.S. from 1983 through the early 1990s. Taking a daily supplement containing 200g of selenium did not affect recurrence of skin cancer, but significantly reduced the occurrence and death from total cancers. The incidence of prostate cancer, colorectal cancer, and lung cancer was notably lower in the group given selenium supplements.
Research suggests that selenium affects cancer risk in two ways. As an anti-oxidant, selenium can help protect the body from damaging effects of free radicals. Selenium may also prevent or slow tumor growth. Certain breakdown products of selenium are believed to prevent tumor growth by enhancing immune cell activity and suppressing development of blood vessels to the tumor .
The SELECT study, a long-term study sponsored by the NIH, is investigating whether supplemental selenium and/or vitamin E can decrease the risk of prostate cancer in healthy men. Past evidence as well as pre-clinical trials for the SELECT study suggests that these two nutrients may be effective in preventing prostate cancer. A daily supplement containing 200 g of selenium will be given to individuals in the selenium-only study group, while men in the combined-nutrients group will receive a daily supplement containing 200g selenium and 400 mg vitamin E. The study, which will span from 2001 to 2013, will include 32,400 healthy adult men .
Selenium and heart disease_
Some population surveys have suggested an association between lower antioxidant intake and a greater incidence of heart disease. Evidence also suggests that oxidative stress from free radicals, which are natural by-products of oxygen metabolism, may promote heart disease. For example, it is the oxidized form of low-density lipoproteins (LDL, often called "bad" cholesterol) that promotes plaque build-up in coronary arteries. Selenium is one of a group of antioxidants that may help limit the oxidation of LDL cholesterol and thereby help to prevent coronary artery disease . Currently there is insufficient evidence available to recommend selenium supplements for the prevention of coronary heart disease.
Selenium and arthritis_
Surveys indicate that individuals with rheumatoid arthritis, a chronic disease that causes pain, stiffness, swelling, and loss of function in joints, have reduced selenium levels in their blood. In addition, some individuals with arthritis have a low selenium intake. __The body's immune system naturally makes free radicals that can help destroy invading organisms and damaged tissue, but that can also harm healthy tissue. Selenium, as an antioxidant, may help to relieve symptoms of arthritis by controlling levels of free radicals. Current findings are considered preliminary, and further research is needed before selenium supplements can be recommended for individuals with arthritis.
Thursday, December 14, 2006
Moderate Drinking May Help Older Women Live Longer
Significant Benefits Found in Cardiovascular Health and Overall Quality of Life
A study published in Journal of the American Geriatrics Society finds that moderate alcohol intake (1-2 drinks/day for 3-6 days/week, depending on alcoholic content) may lead to increased quality of life and survival in older women. The Australian Longitudinal Study on Women’s Health followed nearly 12,000 women in their 70’s over a 6 year period. The group was comprised of non-drinkers, occasional drinkers and moderate drinkers.
The study found that non-drinkers and women who rarely drank had a significantly higher risk of dying during the survey period than did women who drank moderately. Of those who survived, the women who drank the least reported the lowest health-related quality of life. Previous studies have shown that women who have at least one drink per day stand at a lower risk for cardiovascular disease and ischemic stroke than non-drinkers.
“The results of this study indicate that moderate alcohol intake in keeping with current guidelines may carry some health benefits for older women,” says Dr. Julie Ellen Byles, author of the study. This contrasts previous studies which have suggested that moderate alcohol intake can be detrimental to older women and may lead to accidents, cancers, even dementia.
The potential causes of increased health and survival may be ingredients found in wine or ethanol, the social and pleasurable benefits of drinking or the improved appetite and nutrition that often accompanies modest alcohol intake. The author notes that the study does not advocate non-drinkers to begin drinking. Changes in diet need to be determined through consultation with a doctor due to the potential complications of mixing alcohol and medication.
A study published in Journal of the American Geriatrics Society finds that moderate alcohol intake (1-2 drinks/day for 3-6 days/week, depending on alcoholic content) may lead to increased quality of life and survival in older women. The Australian Longitudinal Study on Women’s Health followed nearly 12,000 women in their 70’s over a 6 year period. The group was comprised of non-drinkers, occasional drinkers and moderate drinkers.
The study found that non-drinkers and women who rarely drank had a significantly higher risk of dying during the survey period than did women who drank moderately. Of those who survived, the women who drank the least reported the lowest health-related quality of life. Previous studies have shown that women who have at least one drink per day stand at a lower risk for cardiovascular disease and ischemic stroke than non-drinkers.
“The results of this study indicate that moderate alcohol intake in keeping with current guidelines may carry some health benefits for older women,” says Dr. Julie Ellen Byles, author of the study. This contrasts previous studies which have suggested that moderate alcohol intake can be detrimental to older women and may lead to accidents, cancers, even dementia.
The potential causes of increased health and survival may be ingredients found in wine or ethanol, the social and pleasurable benefits of drinking or the improved appetite and nutrition that often accompanies modest alcohol intake. The author notes that the study does not advocate non-drinkers to begin drinking. Changes in diet need to be determined through consultation with a doctor due to the potential complications of mixing alcohol and medication.
Wednesday, December 13, 2006
Oral Cancer Detection
One person dies every hour from oral cancer in the United States. And while the American Cancer Society estimates that overall cancer incidence and deaths have decreased, oral cancer incidence rose 5.5 percent, and oral cancer deaths increased 1.5 percent over the last reporting period. Late detection of oral cancer is the primary cause of high mortality rates associated with this disease.
Midwest Dental doctors are offering a new screening tool that helps detect oral cancer earlier. Dr. Jeff Moos, president and CEO of Midwest Dental, announced that the new technology, known as ViziLite Plus is now available in all Midwest Dental practices, including the office in Chetek.
"Midwest Dental is committed to leading the fight against oral cancer and recognizes that early detection is the key to reducing the mortality rate associated with this disease," said Dr. Moos. "We are proud to provide ViziLite exams as an integral part of our current annual comprehensive oral cancer screening program and as a way to enhance and protect our patients' overall health."
According to the American Cancer Society, oral cancer is 82 percent curable if discovered in its early stages. ViziLite technology, when used in conjunction with the standard oral cancer examination, has been proven superior to the unaided exam in numerous clinical trials involving over 13,000 patients.
ViziLite is a quick and painless exam. The patient uses a rinse to dry the tissue in the mouth. Using a special glow stick, the dentist looks for abnormalities. Anything that is abnormal appears white, while healthy tissue absorbs the light and appears dark.
As with other types of cancer, age is the primary risk factor for oral cancer, with 95 percent of oral cancer victims being 40 and older. However, all adults age 18 and older are considered to be at increased risk for oral cancer. Oral cancer risk by patient profile is listed below:
Increased risk - Patients age 18-39; sexually active Human Papilloma Virus (HPV strain 16-18);
High risk - Patients age 40 and older; tobacco users 18 years and older;
Highest risk - Patients age 40 and older and lifestyle risk factors (tobacco use) and/or patients with a history of oral cancer.
The increased prevalence of (HPV) Human Papilloma Virus (a sexually transmitted disease linked to cervical cancer) has raised concern with oral cancer in young adults having no other risk factors.
"Many patients are glad to have us take this extra precaution to protect them from the devastation of oral cancer," said Dr. Moos. "The ViziLite exam can absolutely help save lives by allowing our doctors to detect pre-cancerous conditions as well as the disease itself."
Midwest Dental doctors are offering a new screening tool that helps detect oral cancer earlier. Dr. Jeff Moos, president and CEO of Midwest Dental, announced that the new technology, known as ViziLite Plus is now available in all Midwest Dental practices, including the office in Chetek.
"Midwest Dental is committed to leading the fight against oral cancer and recognizes that early detection is the key to reducing the mortality rate associated with this disease," said Dr. Moos. "We are proud to provide ViziLite exams as an integral part of our current annual comprehensive oral cancer screening program and as a way to enhance and protect our patients' overall health."
According to the American Cancer Society, oral cancer is 82 percent curable if discovered in its early stages. ViziLite technology, when used in conjunction with the standard oral cancer examination, has been proven superior to the unaided exam in numerous clinical trials involving over 13,000 patients.
ViziLite is a quick and painless exam. The patient uses a rinse to dry the tissue in the mouth. Using a special glow stick, the dentist looks for abnormalities. Anything that is abnormal appears white, while healthy tissue absorbs the light and appears dark.
As with other types of cancer, age is the primary risk factor for oral cancer, with 95 percent of oral cancer victims being 40 and older. However, all adults age 18 and older are considered to be at increased risk for oral cancer. Oral cancer risk by patient profile is listed below:
Increased risk - Patients age 18-39; sexually active Human Papilloma Virus (HPV strain 16-18);
High risk - Patients age 40 and older; tobacco users 18 years and older;
Highest risk - Patients age 40 and older and lifestyle risk factors (tobacco use) and/or patients with a history of oral cancer.
The increased prevalence of (HPV) Human Papilloma Virus (a sexually transmitted disease linked to cervical cancer) has raised concern with oral cancer in young adults having no other risk factors.
"Many patients are glad to have us take this extra precaution to protect them from the devastation of oral cancer," said Dr. Moos. "The ViziLite exam can absolutely help save lives by allowing our doctors to detect pre-cancerous conditions as well as the disease itself."
Year-round contraceptive, elimination of menstrual cycles safe, study shows
Researchers for the first time have demonstrated the safety and effectiveness of continuous-use oral contraceptives that can eliminate menstrual cycles, according to a study published in the December issue of Contraception.
While low-dose oral contraceptives reducing the number of menstrual periods to four are on the market, this study marks the first time researchers have shown that it's safe to eliminate them, said lead investigator David F. Archer, M.D., professor of obstetrics and gynecology at Eastern Virginia Medical School.
"It is felt that the relief of menstrual cycle symptoms during continuous use of the contraceptive is a significant improvement in the quality of life," said Archer.
Traditional birth-control regimens include 21 days of active hormones with seven days of placebos to continue monthly menstruation. During menstruation, many women suffer a variety of symptoms including headaches, bloating and irritability, Archer said.
In the study, conducted at 92 sites in North America, researchers used a birth-control pill consisting of 20 micrograms of ethinyl estradiol and 90 micrograms of levonorgestrel, a formulation being developed by Wyeth Pharmaceuticals under the name Lybrel. Healthy, sexually active women between 18 and 49 years old were given a continuous regimen without any breaks or placebos.
During the course of the study, which lasted more than 18 months, the median and mean number of bleeding days decreased progressively. For the 2134 subjects enrolled, 79 percent reported an absence of bleeding after one year while 58.7 percent reported cessation of menstrual cycles.
The study results demonstrated that the continuous-use, low-dose regimen was safe and as effective as traditional oral contraceptives.
While low-dose oral contraceptives reducing the number of menstrual periods to four are on the market, this study marks the first time researchers have shown that it's safe to eliminate them, said lead investigator David F. Archer, M.D., professor of obstetrics and gynecology at Eastern Virginia Medical School.
"It is felt that the relief of menstrual cycle symptoms during continuous use of the contraceptive is a significant improvement in the quality of life," said Archer.
Traditional birth-control regimens include 21 days of active hormones with seven days of placebos to continue monthly menstruation. During menstruation, many women suffer a variety of symptoms including headaches, bloating and irritability, Archer said.
In the study, conducted at 92 sites in North America, researchers used a birth-control pill consisting of 20 micrograms of ethinyl estradiol and 90 micrograms of levonorgestrel, a formulation being developed by Wyeth Pharmaceuticals under the name Lybrel. Healthy, sexually active women between 18 and 49 years old were given a continuous regimen without any breaks or placebos.
During the course of the study, which lasted more than 18 months, the median and mean number of bleeding days decreased progressively. For the 2134 subjects enrolled, 79 percent reported an absence of bleeding after one year while 58.7 percent reported cessation of menstrual cycles.
The study results demonstrated that the continuous-use, low-dose regimen was safe and as effective as traditional oral contraceptives.
Fish oil to protect against disease
by: Dr. Michael Dody on 11/30/2006
You want to increase your overall health and energy level. You want to prevent heart disease, cancer, depression and Alzheimer's. Perhaps you also want to treat rheumatoid arthritis, diabetes, ulcerative colitis, Raynaud's disease and a host of other diseases. One of the most important things you can do for all of these is increase your intake of the omega-3 fats found in fish oil and cod liver oil, and reduce your intake of omega-6 fats.
These two types of fat, omega-3 and omega-6, are both essential for human health. However, the typical American consumes far too many omega-6 fats in their diet while consuming very low levels of omega-3. The ideal ratio of omega-6 to omega-3 fats is 1:1. Our ancestors evolved over millions of years on this ratio. Today, though, our ratio of omega-6 to omega-3 averages from 20:1 to 50:1! That spells serious danger for you, and as is now (finally!) being reported throughout even the mainstream health media, lack of omega-3 from fish oil is one of the most serious health issues plaguing contemporary society.
The primary sources of omega-6 are corn, soy, canola, safflower and sunflower oil; these oils are overabundant in the typical diet, which explains our excess omega-6 levels. Avoid or limit these oils. Omega-3, meanwhile, is typically found in flaxseed oil, walnut oil, and fish.
By far, the best type of omega-3 fats are those found in that last category, fish. That's because the omega-3 in fish is high in two fatty acids crucial to human health, DHA and EPA. These two fatty acids are pivotal in preventing heart disease, cancer, and many other diseases. The human brain is also highly dependent on DHA - low DHA levels have been linked to depression, schizophrenia, memory loss, and a higher risk of developing Alzheimer's. Researchers are now also linking inadequate intake of these omega-3 fats in pregnant women to premature birth and low birth weight, and to hyperactivity in children.
Sadly, though, eating most fresh fish, whether from the ocean, lakes and streams, or farm-raised, is no longer recommended. Mercury levels in almost all fish have now hit dangerously high levels across the world, and the risk of this mercury to your health now outweighs the fish's omega-3 benefits. However, because fish would otherwise be immensely healthy, I had been searching for a safe source of fish for some time -- and finally discovered one. The Vital Choice Alaskan wild red salmon is the one source of salmon or any fish that, via independent lab-testing, I have discovered is safe from mercury and other toxins. In addition to being mercury-free, the Vital Choice Alaskan salmon is loaded with omega-3 with EPA and DHA , is high in antioxidants to help you live longer, and tastes absolutely delicious.
Routine consumption of fish oil is another highly recommended method of increasing your omega-3 intake and improving your health, and is also the most convenient for today's busy lifestyles. Fish oil contains high levels of the best omega-3 fats - those with the EPA and DHA fatty acids - and, as it is in pure form, does not pose the mercury risk of fresh fish.
You want to increase your overall health and energy level. You want to prevent heart disease, cancer, depression and Alzheimer's. Perhaps you also want to treat rheumatoid arthritis, diabetes, ulcerative colitis, Raynaud's disease and a host of other diseases. One of the most important things you can do for all of these is increase your intake of the omega-3 fats found in fish oil and cod liver oil, and reduce your intake of omega-6 fats.
These two types of fat, omega-3 and omega-6, are both essential for human health. However, the typical American consumes far too many omega-6 fats in their diet while consuming very low levels of omega-3. The ideal ratio of omega-6 to omega-3 fats is 1:1. Our ancestors evolved over millions of years on this ratio. Today, though, our ratio of omega-6 to omega-3 averages from 20:1 to 50:1! That spells serious danger for you, and as is now (finally!) being reported throughout even the mainstream health media, lack of omega-3 from fish oil is one of the most serious health issues plaguing contemporary society.
The primary sources of omega-6 are corn, soy, canola, safflower and sunflower oil; these oils are overabundant in the typical diet, which explains our excess omega-6 levels. Avoid or limit these oils. Omega-3, meanwhile, is typically found in flaxseed oil, walnut oil, and fish.
By far, the best type of omega-3 fats are those found in that last category, fish. That's because the omega-3 in fish is high in two fatty acids crucial to human health, DHA and EPA. These two fatty acids are pivotal in preventing heart disease, cancer, and many other diseases. The human brain is also highly dependent on DHA - low DHA levels have been linked to depression, schizophrenia, memory loss, and a higher risk of developing Alzheimer's. Researchers are now also linking inadequate intake of these omega-3 fats in pregnant women to premature birth and low birth weight, and to hyperactivity in children.
Sadly, though, eating most fresh fish, whether from the ocean, lakes and streams, or farm-raised, is no longer recommended. Mercury levels in almost all fish have now hit dangerously high levels across the world, and the risk of this mercury to your health now outweighs the fish's omega-3 benefits. However, because fish would otherwise be immensely healthy, I had been searching for a safe source of fish for some time -- and finally discovered one. The Vital Choice Alaskan wild red salmon is the one source of salmon or any fish that, via independent lab-testing, I have discovered is safe from mercury and other toxins. In addition to being mercury-free, the Vital Choice Alaskan salmon is loaded with omega-3 with EPA and DHA , is high in antioxidants to help you live longer, and tastes absolutely delicious.
Routine consumption of fish oil is another highly recommended method of increasing your omega-3 intake and improving your health, and is also the most convenient for today's busy lifestyles. Fish oil contains high levels of the best omega-3 fats - those with the EPA and DHA fatty acids - and, as it is in pure form, does not pose the mercury risk of fresh fish.
Current Issues and Controversies about Vitamin E
Vitamin E and Heart Disease
Preliminary research has led to a widely held belief that vitamin E may help prevent or delay coronary heart disease.
Researchers have reported that oxidative changes to LDL-cholesterol (sometimes called "bad" cholesterol) promote blockages (atherosclerosis) in coronary arteries that may lead to heart attacks. Vitamin E may help prevent or delay coronary heart disease by limiting the oxidation of LDL-cholesterol. Vitamin E also may help prevent the formation of blood clots, which could lead to a heart attack. Observational studies have associated lower rates of heart disease with higher vitamin E intake. A study of approximately 90,000 nurses suggested that the incidence of heart disease was 30% to 40% lower among nurses with the highest intake of vitamin E from diet and supplements. Researchers found that the apparent benefit was mainly associated with intake of vitamin E from dietary supplements. High vitamin E intake from food was not associated with significant cardiac risk reduction. A 1994 review of 5,133 Finnish men and women aged 30-69 years also suggested that increased dietary intake of vitamin E was associated with decreased mortality (death) from heart disease.
Even though these observations are promising, randomized clinical trials raise questions about the efficacy of vitamin E supplements in the prevention of heart disease. The Heart Outcomes Prevention Evaluation (HOPE) Study followed almost 10,000 patients for 4.5 years who were at high risk for heart attack or stroke. In this intervention study the subjects who received 265 mg (400 IU) of vitamin E daily did not experience significantly fewer cardiovascular events or hospitalizations for heart failure or chest pain when compared to those who received a placebo (sugar pill). The researchers suggested that it is unlikely that the vitamin E supplement provided any protection against cardiovascular disease in the HOPE study. This study is continuing, with the goal of determining whether a longer duration of intervention with vitamin E supplements will provide any protection against cardiovascular disease.
In a study sponsored by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health, postmenopausal women with heart disease who took supplements providing 400 IU vitamin E and 500 mg vitamin C twice a day, either alone or in combination with hormones, did not have fewer heart attacks or deaths. There was also no change in progression of their coronary disease. This study, The Women's Angiographic Vitamin and Estrogen (WAVE) trial, studied 423 postmenopausal women at seven clinical centers in the U.S. and Canada. In postmenopausal women with coronary disease enrolled in this trial, neither hormone replacement therapy nor antioxidant vitamin supplements provided cardiovascular benefit.
Results of the Women's Health Study, the Women's Antioxidant and Cardiovascular Study and the SuVIMAX study, all of which are investigating the effects of vitamin supplements on the progression of coronary heart disease, are due in 2005 and will provide additional information on the association between vitamin E supplements and cardiovascular disease.
Vitamin E and Cancer
'
Antioxidants such as vitamin E are believed to help protect cell membranes against the damaging effects of free radicals, which may contribute to the development of chronic diseases such as cancer. Vitamin E also may block the formation of nitrosamines, which are carcinogens formed in the stomach from nitrites consumed in the diet. It also may protect against the development of cancers by enhancing immune function. Unfortunately, human trials and surveys that have tried to associate vitamin E intake with incidence of cancer have been generally inconclusive.
Some evidence associates higher intake of vitamin E with a decreased incidence of prostate cancer and breast cancer. However, an examination of the effect of dietary factors, including vitamin E, on incidence of postmenopausal breast cancer in over 18,000 women from New York State did not associate a greater vitamin E intake with a reduced risk of developing breast cancer.
A study of women in Iowa provides evidence that an increased dietary intake of vitamin E may decrease the risk of colon cancer, especially in women under 65 years of age. On the other hand, a study of 87,998 females from the Nurses' Health Study and 47,344 males from the Health Professionals Follow-up Study failed to support the theory that an increased dietary intake of vitamin E may decrease the risk of colon cancer.
The American Cancer society recently released the results of a long-term study that evaluated the effect of regular use of vitamin C and vitamin E supplements on bladder cancer mortality in almost 1,000,000 adults in the U.S. The study, conducted between the years 1982 to 1998, found that subjects who regularly consumed a vitamin E supplement for longer than 10 years had a reduced risk of death from bladder cancer. No benefit was seen from vitamin C supplements.
At this time researchers cannot confidently recommend vitamin E supplements for the prevention of cancer because the evidence on this issue is inconsistent and limited.
Vitamin E and Cataracts
Cataracts are abnormal growths in the lens of the eye. These growths cloud vision. They also increase the risk of disability and blindness in aging adults. Antioxidants are being studied to determine whether they can help prevent or delay cataract growth. Observational studies have found that lens clarity, which is used to diagnose cataracts, was better in regular users of vitamin E supplements and in persons with higher blood levels of vitamin E. A study of middle-aged male smokers, however, did not demonstrate any effect from vitamin E supplements on the incidence of cataract formation. The effects of smoking, a major risk factor for developing cataracts, may have overridden any potential benefit from the vitamin E, but the conflicting results also indicate a need for further studies before researchers can confidently recommend extra vitamin E for the prevention of cataracts.
Preliminary research has led to a widely held belief that vitamin E may help prevent or delay coronary heart disease.
Researchers have reported that oxidative changes to LDL-cholesterol (sometimes called "bad" cholesterol) promote blockages (atherosclerosis) in coronary arteries that may lead to heart attacks. Vitamin E may help prevent or delay coronary heart disease by limiting the oxidation of LDL-cholesterol. Vitamin E also may help prevent the formation of blood clots, which could lead to a heart attack. Observational studies have associated lower rates of heart disease with higher vitamin E intake. A study of approximately 90,000 nurses suggested that the incidence of heart disease was 30% to 40% lower among nurses with the highest intake of vitamin E from diet and supplements. Researchers found that the apparent benefit was mainly associated with intake of vitamin E from dietary supplements. High vitamin E intake from food was not associated with significant cardiac risk reduction. A 1994 review of 5,133 Finnish men and women aged 30-69 years also suggested that increased dietary intake of vitamin E was associated with decreased mortality (death) from heart disease.
Even though these observations are promising, randomized clinical trials raise questions about the efficacy of vitamin E supplements in the prevention of heart disease. The Heart Outcomes Prevention Evaluation (HOPE) Study followed almost 10,000 patients for 4.5 years who were at high risk for heart attack or stroke. In this intervention study the subjects who received 265 mg (400 IU) of vitamin E daily did not experience significantly fewer cardiovascular events or hospitalizations for heart failure or chest pain when compared to those who received a placebo (sugar pill). The researchers suggested that it is unlikely that the vitamin E supplement provided any protection against cardiovascular disease in the HOPE study. This study is continuing, with the goal of determining whether a longer duration of intervention with vitamin E supplements will provide any protection against cardiovascular disease.
In a study sponsored by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health, postmenopausal women with heart disease who took supplements providing 400 IU vitamin E and 500 mg vitamin C twice a day, either alone or in combination with hormones, did not have fewer heart attacks or deaths. There was also no change in progression of their coronary disease. This study, The Women's Angiographic Vitamin and Estrogen (WAVE) trial, studied 423 postmenopausal women at seven clinical centers in the U.S. and Canada. In postmenopausal women with coronary disease enrolled in this trial, neither hormone replacement therapy nor antioxidant vitamin supplements provided cardiovascular benefit.
Results of the Women's Health Study, the Women's Antioxidant and Cardiovascular Study and the SuVIMAX study, all of which are investigating the effects of vitamin supplements on the progression of coronary heart disease, are due in 2005 and will provide additional information on the association between vitamin E supplements and cardiovascular disease.
Vitamin E and Cancer
'
Antioxidants such as vitamin E are believed to help protect cell membranes against the damaging effects of free radicals, which may contribute to the development of chronic diseases such as cancer. Vitamin E also may block the formation of nitrosamines, which are carcinogens formed in the stomach from nitrites consumed in the diet. It also may protect against the development of cancers by enhancing immune function. Unfortunately, human trials and surveys that have tried to associate vitamin E intake with incidence of cancer have been generally inconclusive.
Some evidence associates higher intake of vitamin E with a decreased incidence of prostate cancer and breast cancer. However, an examination of the effect of dietary factors, including vitamin E, on incidence of postmenopausal breast cancer in over 18,000 women from New York State did not associate a greater vitamin E intake with a reduced risk of developing breast cancer.
A study of women in Iowa provides evidence that an increased dietary intake of vitamin E may decrease the risk of colon cancer, especially in women under 65 years of age. On the other hand, a study of 87,998 females from the Nurses' Health Study and 47,344 males from the Health Professionals Follow-up Study failed to support the theory that an increased dietary intake of vitamin E may decrease the risk of colon cancer.
The American Cancer society recently released the results of a long-term study that evaluated the effect of regular use of vitamin C and vitamin E supplements on bladder cancer mortality in almost 1,000,000 adults in the U.S. The study, conducted between the years 1982 to 1998, found that subjects who regularly consumed a vitamin E supplement for longer than 10 years had a reduced risk of death from bladder cancer. No benefit was seen from vitamin C supplements.
At this time researchers cannot confidently recommend vitamin E supplements for the prevention of cancer because the evidence on this issue is inconsistent and limited.
Vitamin E and Cataracts
Cataracts are abnormal growths in the lens of the eye. These growths cloud vision. They also increase the risk of disability and blindness in aging adults. Antioxidants are being studied to determine whether they can help prevent or delay cataract growth. Observational studies have found that lens clarity, which is used to diagnose cataracts, was better in regular users of vitamin E supplements and in persons with higher blood levels of vitamin E. A study of middle-aged male smokers, however, did not demonstrate any effect from vitamin E supplements on the incidence of cataract formation. The effects of smoking, a major risk factor for developing cataracts, may have overridden any potential benefit from the vitamin E, but the conflicting results also indicate a need for further studies before researchers can confidently recommend extra vitamin E for the prevention of cataracts.
Tuesday, December 12, 2006
Resveratrol Could Protect Against Stroke
Resveratrol, a compound found in grapes, red wine and peanuts, can improve blood flow in the brain by 30 per cent, thereby reducing the risk of stroke, according to the results of a rat study.
Researchers at the National Taiwan Normal University and the National Chia-Yi University report that rats with induced reduction of blood flow (ischemia) in the brain experienced an improved blood flow from a single dose of resveratrol.
“We found that resveratrol administration… led to cerebral blood flow elevation and protected animals from ischemia-induced neuron loss,” said lead author Kwok Tung Lu.
Strokes occur when blood clots or an artery bursts in the brain and interrupts the blood supply to a part of the brain. It is the leading cause of disability and the third leading cause of death in Europe and the US. According to the Stroke Alliance for Europe (SAFE), about 575,000 deaths are stroke related in Europe every year. In the US, every 45 seconds someone will experience a stroke, according to the American Stroke Association.
The new study, published in the Journal of Agricultural and Food Chemistry (Vol. 54, pp. 3126-3131), divided 60 adult male Wistar rats into three equal groups. The first group was the control. The second group underwent the induction of cerebral ischemia, and the third group underwent the same operation but also received an intravenous dose of resveratrol (20 milligrams per kilogram body weight).
Although no change to mean blood pressure or heart rate was observed, cerebral blood flow in the second group decreased by 65 per cent compared to the control group. The ischemia plus resveratrol group's blood flow also decreased, but by only 35 per cent.
The researchers also found that the concentration of nitric oxide (NO) in the affected part of the brain was 25 per cent higher than for both the control and ischemia-only group. NO is a molecule used by lining of blood vessels (endothelium) to signal to the surrounding muscle to relax – this dilates the blood vessel and increases the blood flow.
“We suggested that resveratrol may elicit neuroprotective effects by stimulating NO formation or release, which increases cerebral blood flow,” said Lu.
The authors said that further investigation of the effects of resveratrol was needed. Of particular interest is the dose needed to produce protection While resveratrol has been the subject of various studies, particularly in relation to heart health, recent studies have reported brain protecting effects from grape juice or wine – an effect linked to a synergy between the various polyphenols present.
A recent study using Concord grape juice by researchers from Tuft's University reported that the combination of the polyphenols could decrease the effects of aging on the brain.
“It may be that the whole is greater than the sum of its parts,” lead author Barbara Shukitt-Hale wrote in the journal Nutrition (Vol. 22, pp. 295-302).
The amount of resveratrol in a bottle of red wine can vary between types of grapes and growing seasons. But nearly all dark red wines – merlot, cabernet, zinfandel, shiraz and pinot noir – contain resveratrol.
The health implications of red wine consumption appear to be filtering through to the consumer. A report from analysts Euromonitor in 2004 predicted that still red wine will exhibit by far the fastest growth in both volume and value terms between 2002 and 2007.
Their study claims that red wine is forecast to record global value sales of $82bn (€61.5bn) in 2007, a rise of some 31 per cent from 2002.
However, experts are quick to warn that moderation is the key. A study from Harvard University last year reported that people who have three or more alcoholic drinks per day have a significantly higher risk of stroke. Lowest risk was observed for those who had one, or maybe two, drinks every other day.
Researchers at the National Taiwan Normal University and the National Chia-Yi University report that rats with induced reduction of blood flow (ischemia) in the brain experienced an improved blood flow from a single dose of resveratrol.
“We found that resveratrol administration… led to cerebral blood flow elevation and protected animals from ischemia-induced neuron loss,” said lead author Kwok Tung Lu.
Strokes occur when blood clots or an artery bursts in the brain and interrupts the blood supply to a part of the brain. It is the leading cause of disability and the third leading cause of death in Europe and the US. According to the Stroke Alliance for Europe (SAFE), about 575,000 deaths are stroke related in Europe every year. In the US, every 45 seconds someone will experience a stroke, according to the American Stroke Association.
The new study, published in the Journal of Agricultural and Food Chemistry (Vol. 54, pp. 3126-3131), divided 60 adult male Wistar rats into three equal groups. The first group was the control. The second group underwent the induction of cerebral ischemia, and the third group underwent the same operation but also received an intravenous dose of resveratrol (20 milligrams per kilogram body weight).
Although no change to mean blood pressure or heart rate was observed, cerebral blood flow in the second group decreased by 65 per cent compared to the control group. The ischemia plus resveratrol group's blood flow also decreased, but by only 35 per cent.
The researchers also found that the concentration of nitric oxide (NO) in the affected part of the brain was 25 per cent higher than for both the control and ischemia-only group. NO is a molecule used by lining of blood vessels (endothelium) to signal to the surrounding muscle to relax – this dilates the blood vessel and increases the blood flow.
“We suggested that resveratrol may elicit neuroprotective effects by stimulating NO formation or release, which increases cerebral blood flow,” said Lu.
The authors said that further investigation of the effects of resveratrol was needed. Of particular interest is the dose needed to produce protection While resveratrol has been the subject of various studies, particularly in relation to heart health, recent studies have reported brain protecting effects from grape juice or wine – an effect linked to a synergy between the various polyphenols present.
A recent study using Concord grape juice by researchers from Tuft's University reported that the combination of the polyphenols could decrease the effects of aging on the brain.
“It may be that the whole is greater than the sum of its parts,” lead author Barbara Shukitt-Hale wrote in the journal Nutrition (Vol. 22, pp. 295-302).
The amount of resveratrol in a bottle of red wine can vary between types of grapes and growing seasons. But nearly all dark red wines – merlot, cabernet, zinfandel, shiraz and pinot noir – contain resveratrol.
The health implications of red wine consumption appear to be filtering through to the consumer. A report from analysts Euromonitor in 2004 predicted that still red wine will exhibit by far the fastest growth in both volume and value terms between 2002 and 2007.
Their study claims that red wine is forecast to record global value sales of $82bn (€61.5bn) in 2007, a rise of some 31 per cent from 2002.
However, experts are quick to warn that moderation is the key. A study from Harvard University last year reported that people who have three or more alcoholic drinks per day have a significantly higher risk of stroke. Lowest risk was observed for those who had one, or maybe two, drinks every other day.
Red wine again linked to slowing Alzheimer's
A Mount Sinai School of Medicine study found giving mice with amyloid plaques red wine slows their memory loss and brain cell death - adding to a body of science linking compounds in the beverage to slowing the Alzheimer's disease-related symptom.
In the study - set to for publication in November's Federation of American Societies for Experimental Biology Journal - wine-drinking mice learned to escape from a maze significantly faster than mice drinking alcohol-spiked water or water.
The results could have implications for formulators in the production of supplements for age-related conditions.
According to the Alzheimers Society, there are nearly 18 million people in the world with dementia. Around 55 percent of those who suffer from dementia have Alzheimer's.
In the Mount Sinai study, the mice's wine intake was aligned to what is the equivalent of moderate consumption in humans - a five-ounce glass per day for women and two for men.
In the past, both alcohol and a red wine compound, resveratrol, have been linked to a reduction in the onset of dementia.
For several months, the Mount Sinai mice were given cabernet sauvignon or ethanol in their drinking water, while another group of mice drank plain water. All the mice had amyloid plaques in their brains that occur in humans with Alzheimer's disease.
The research team, led by Dr. Giulio Maria Pasinetti, assessed the mice's memory by testing their ability to get out of a maze. The wine-drinking mice were able to exit the maze significantly faster than those drinking alcohol-spiked water or water only, the scientists found.
The study only advocates moderate red wine consumption as part of an overall healthy lifestyle.
In the study - set to for publication in November's Federation of American Societies for Experimental Biology Journal - wine-drinking mice learned to escape from a maze significantly faster than mice drinking alcohol-spiked water or water.
The results could have implications for formulators in the production of supplements for age-related conditions.
According to the Alzheimers Society, there are nearly 18 million people in the world with dementia. Around 55 percent of those who suffer from dementia have Alzheimer's.
In the Mount Sinai study, the mice's wine intake was aligned to what is the equivalent of moderate consumption in humans - a five-ounce glass per day for women and two for men.
In the past, both alcohol and a red wine compound, resveratrol, have been linked to a reduction in the onset of dementia.
For several months, the Mount Sinai mice were given cabernet sauvignon or ethanol in their drinking water, while another group of mice drank plain water. All the mice had amyloid plaques in their brains that occur in humans with Alzheimer's disease.
The research team, led by Dr. Giulio Maria Pasinetti, assessed the mice's memory by testing their ability to get out of a maze. The wine-drinking mice were able to exit the maze significantly faster than those drinking alcohol-spiked water or water only, the scientists found.
The study only advocates moderate red wine consumption as part of an overall healthy lifestyle.
Red Wine Compound May Extend Life
- Resveratrol, a polyphenol found in red wine, extended survival rates of mice and prevented the negative effects of high-calorie diets, says a new study published in Nature.
The study, described by an independent expert as potentially “the breakthrough of the year”, adds to a growing body of research linking resveratrol and red wine consumption to a range of beneficial health effects, including brain and mental health, and cardiovascular health.
"The "healthspan" benefits we saw in the obese mice [fed] resveratrol, such as increased insulin sensitivity, decreased glucose levels, healthier heart and liver tissues, are positive clinical indicators and may mean we can stave off in humans age-related diseases such as type 2 diabetes, heart disease, and cancer, but only time and more research will tell," said co-author David Sinclair from Harvard Medical School.
The new study, published on-line in Nature (doi: 10.1038/nature05354), looked at the effects of the feeding middle-aged mice (52 weeks old) one of three diets: a standard mouse diet, a high calorie (fat) diet and a high calorie (fat) diet supplemented with resveratrol.
At 60 weeks of age, the researchers report that the survival curves of the high calorie and the high calorie/resveratrol groups began to diverge, with the resveratrol group showing a 3-4 month advantage in survival.
When the mice reached ‘old age' (114 weeks), lead author Joseph Baur and his colleagues report that more than 50 per cent of the high calorie mice had died compared to less than 33 per cent of the high calorie mice receiving resveratrol.
Baur reported that the high calorie mice (no resveratrol supplement) were found to have increased plasma levels of insulin, glucose and insulin-like growth factor (IGF) 1 - markers that in humans predict the onset of diabetes - when compared with their overweight counterparts supplemented with resveratrol.
Pathological studies of the heart tissues of mice from the three diet groups showed that the abundance of fatty lesions, degeneration and inflammation were significantly less for the standard diet and resveratrol-supplemented group (1.6 and 1.2 points on a relative scale of 0-4), compared to the high calorie diet group (3.2 points).
"After six months, resveratrol essentially prevented most of the negative effects of the high calorie diet," said Rafael de Cabo, Ph.D., from the National Institute on Aging (NIA).
The mechanism behind the apparent benefits is proposed to be related to activation of an enzyme called SIRT1. To determine this, they looked at the amount of a specific chemical modification (acetylation) on the molecule PGC-1alpha. The research team found that levels of PGC-1alpha were three-fold lower in the resveratrol-supplemented mice than in the high calorie mice, consistent with what would be expected when SIRT1 was being activated by resveratrol, they said.
“This study shows that an orally available small molecul at doses achievable in humans can safely reduce many of the negative consequences of excess caloric intake, with an overall improvement in health and survival,” concluded the researchers.
While the results are very promising, Richard Hodes, M.D., director of the NIA, added a note of perspective and caution: "At the same time, it should be cautioned that this is a study of male mice, and we still have much to learn about resveratrol's safety and effectiveness in humans."
Professor Steve Bloom, an obesity researcher at Imperial College, London, told the BBC: "If we start with the idea that there is an evolutionary advantage for the life expectation of each species, and this is tied into scarcity or abundance of food.
"If there is plenty of food, you'll live a very active life for a while, and then drop dead. If there isn't much food, because reproduction takes more energy, it is better to keep a small number of animals going for longer.
"There is a system to regulate it, and it looks like resveratrol bypasses this system or may be an endogenous part of that system.
"This paper is extremely interesting - it could be the breakthrough of the year, with massive possibilities for… human beings."
In an accompanying article (Nature, doi:10.1038/nature05308), Matt Kaeberlein and Peter Rabinovitch, from the University of Washington, said: "The safety of resveratrol at the high doses in humans comparable to those used by [the researchers] is unknown, especially over the course of years or even decades, when relatively modest side-effects could have dramatic consequences."
"For now, we counsel patience. Just sit back and relax with a glass of red wine - which alas, has only 0.3 per cent of the relative resveratrol dose given to the gluttonous mice," they said.
The amount of resveratrol in a bottle of red wine can vary between types of grapes and growing seasons, and can vary between 0.2 and 5.8 milligrams per litre. But nearly all dark red wines – merlot, cabernet, zinfandel, shiraz and pinot noir – contain resveratrol.
The study, described by an independent expert as potentially “the breakthrough of the year”, adds to a growing body of research linking resveratrol and red wine consumption to a range of beneficial health effects, including brain and mental health, and cardiovascular health.
"The "healthspan" benefits we saw in the obese mice [fed] resveratrol, such as increased insulin sensitivity, decreased glucose levels, healthier heart and liver tissues, are positive clinical indicators and may mean we can stave off in humans age-related diseases such as type 2 diabetes, heart disease, and cancer, but only time and more research will tell," said co-author David Sinclair from Harvard Medical School.
The new study, published on-line in Nature (doi: 10.1038/nature05354), looked at the effects of the feeding middle-aged mice (52 weeks old) one of three diets: a standard mouse diet, a high calorie (fat) diet and a high calorie (fat) diet supplemented with resveratrol.
At 60 weeks of age, the researchers report that the survival curves of the high calorie and the high calorie/resveratrol groups began to diverge, with the resveratrol group showing a 3-4 month advantage in survival.
When the mice reached ‘old age' (114 weeks), lead author Joseph Baur and his colleagues report that more than 50 per cent of the high calorie mice had died compared to less than 33 per cent of the high calorie mice receiving resveratrol.
Baur reported that the high calorie mice (no resveratrol supplement) were found to have increased plasma levels of insulin, glucose and insulin-like growth factor (IGF) 1 - markers that in humans predict the onset of diabetes - when compared with their overweight counterparts supplemented with resveratrol.
Pathological studies of the heart tissues of mice from the three diet groups showed that the abundance of fatty lesions, degeneration and inflammation were significantly less for the standard diet and resveratrol-supplemented group (1.6 and 1.2 points on a relative scale of 0-4), compared to the high calorie diet group (3.2 points).
"After six months, resveratrol essentially prevented most of the negative effects of the high calorie diet," said Rafael de Cabo, Ph.D., from the National Institute on Aging (NIA).
The mechanism behind the apparent benefits is proposed to be related to activation of an enzyme called SIRT1. To determine this, they looked at the amount of a specific chemical modification (acetylation) on the molecule PGC-1alpha. The research team found that levels of PGC-1alpha were three-fold lower in the resveratrol-supplemented mice than in the high calorie mice, consistent with what would be expected when SIRT1 was being activated by resveratrol, they said.
“This study shows that an orally available small molecul at doses achievable in humans can safely reduce many of the negative consequences of excess caloric intake, with an overall improvement in health and survival,” concluded the researchers.
While the results are very promising, Richard Hodes, M.D., director of the NIA, added a note of perspective and caution: "At the same time, it should be cautioned that this is a study of male mice, and we still have much to learn about resveratrol's safety and effectiveness in humans."
Professor Steve Bloom, an obesity researcher at Imperial College, London, told the BBC: "If we start with the idea that there is an evolutionary advantage for the life expectation of each species, and this is tied into scarcity or abundance of food.
"If there is plenty of food, you'll live a very active life for a while, and then drop dead. If there isn't much food, because reproduction takes more energy, it is better to keep a small number of animals going for longer.
"There is a system to regulate it, and it looks like resveratrol bypasses this system or may be an endogenous part of that system.
"This paper is extremely interesting - it could be the breakthrough of the year, with massive possibilities for… human beings."
In an accompanying article (Nature, doi:10.1038/nature05308), Matt Kaeberlein and Peter Rabinovitch, from the University of Washington, said: "The safety of resveratrol at the high doses in humans comparable to those used by [the researchers] is unknown, especially over the course of years or even decades, when relatively modest side-effects could have dramatic consequences."
"For now, we counsel patience. Just sit back and relax with a glass of red wine - which alas, has only 0.3 per cent of the relative resveratrol dose given to the gluttonous mice," they said.
The amount of resveratrol in a bottle of red wine can vary between types of grapes and growing seasons, and can vary between 0.2 and 5.8 milligrams per litre. But nearly all dark red wines – merlot, cabernet, zinfandel, shiraz and pinot noir – contain resveratrol.
Resveratrol in Red Wine Cuts Colorectal Cancer Risk
Drinking more than three glasses of red wine a week could cut the risk of colorectal cancer by almost 70 per cent, researchers told the 71st Annual Scientific Meeting of the American College of Gastroenterology in Las Vegas.
The potential benefits of the wine have been put down to the resveratrol content of the wine, and adds to an ever growing body of science linking the compound to a range of beneficial health effects, including brain and mental health, and cardiovascular health.
Colorectal cancer accounts for nine per cent of new cancer cases every year worldwide. The highest incidence rates are in the developed world, while Asia and Africa have the lowest incidence rates.
It remains one of the most curable cancers if diagnosis is made early.
The new research, by Joseph Anderson, and his colleagues from the Stony Brook University in New York looked at the drinking habits of 360 red and white drinkers with similar lifestyles and found that, while white wine consumption was not found to have any association with colorectal cancer incidence, regular red wine consumption was linked to a 68 per cent reduced risk of the cancer.
And the researchers told attendees that the active component in wine that may be behind the apparent benefits is most likely resveratrol, an anti-fungal chemical that occurs naturally under the skin of red wine grapes.
“The concentration is significantly higher in red wine than in white wine, because the skins are removed earlier during white-wine production, lessening the amount that is extracted,” said Dr. Anderson.
However, grapes and wine are reported to contain more than 600 different components, including well-characterized antioxidant molecules. Therefore, excluding the possibility that several compounds work in synergy with small amounts of resveratrol to protect against colorectal cancer seems premature.
Indeed, while resveratrol has been the subject of various studies, particularly in relation to heart health, recent studies have reported brain protecting effects from grape juice or wine – an effect linked to a synergy between the various polyphenols present.
A recent study using Concord grape juice by researchers from Tuft's University reported that the combination of the polyphenols could decrease the effects of aging on the brain.
“It may be that the whole is greater than the sum of its parts,” lead author Barbara Shukitt-Hale wrote in the journal Nutrition (Vol. 22, pp. 295-302).
The amount of resveratrol in a bottle of red wine can vary between types of grapes and growing seasons, and can vary between 0.2 and 5.8 milligrams per litre. But nearly all dark red wines – merlot, cabernet, zinfandel, shiraz and pinot noir – contain resveratrol.
The potential benefits of the wine have been put down to the resveratrol content of the wine, and adds to an ever growing body of science linking the compound to a range of beneficial health effects, including brain and mental health, and cardiovascular health.
Colorectal cancer accounts for nine per cent of new cancer cases every year worldwide. The highest incidence rates are in the developed world, while Asia and Africa have the lowest incidence rates.
It remains one of the most curable cancers if diagnosis is made early.
The new research, by Joseph Anderson, and his colleagues from the Stony Brook University in New York looked at the drinking habits of 360 red and white drinkers with similar lifestyles and found that, while white wine consumption was not found to have any association with colorectal cancer incidence, regular red wine consumption was linked to a 68 per cent reduced risk of the cancer.
And the researchers told attendees that the active component in wine that may be behind the apparent benefits is most likely resveratrol, an anti-fungal chemical that occurs naturally under the skin of red wine grapes.
“The concentration is significantly higher in red wine than in white wine, because the skins are removed earlier during white-wine production, lessening the amount that is extracted,” said Dr. Anderson.
However, grapes and wine are reported to contain more than 600 different components, including well-characterized antioxidant molecules. Therefore, excluding the possibility that several compounds work in synergy with small amounts of resveratrol to protect against colorectal cancer seems premature.
Indeed, while resveratrol has been the subject of various studies, particularly in relation to heart health, recent studies have reported brain protecting effects from grape juice or wine – an effect linked to a synergy between the various polyphenols present.
A recent study using Concord grape juice by researchers from Tuft's University reported that the combination of the polyphenols could decrease the effects of aging on the brain.
“It may be that the whole is greater than the sum of its parts,” lead author Barbara Shukitt-Hale wrote in the journal Nutrition (Vol. 22, pp. 295-302).
The amount of resveratrol in a bottle of red wine can vary between types of grapes and growing seasons, and can vary between 0.2 and 5.8 milligrams per litre. But nearly all dark red wines – merlot, cabernet, zinfandel, shiraz and pinot noir – contain resveratrol.
How can people avoid adding holiday weight?
Although some Americans gain five to seven pounds with a diet of big meals and sweets between Thanksgiving and New Year’s Day, most people only gain a pound or two during the holidays, according to a UT Southwestern Medical Center registered dietitian.
But even a slight weight gain, if left intact, can accumulate yearly and endanger health.
“The problem is in gaining a pound or two and not working it off, even with good intentions and New Year’s resolutions. The gain stays on and adds up each year; in a decade it’s 10 or 20 pounds,” said Lona Sandon, assistant professor of clinical nutrition. “That can lead to obesity and related health problems such as hypertension, stroke, diabetes and other maladies.”
So how can people avoid adding holiday weight?
Healthy food choices, eating habits, food preparation and exercise, Ms. Sandon said.
“First, focus on choosing healthy foods instead of concentrating on what you shouldn’t have,” she said. “For instance, seek out cranberries, which have a high level of antioxidants, which protect cells and help the body block urinary-tract infections and prevent plaque formation on teeth.”
Ms. Sandon listed several other healthy or calorie-saving food choices:
Fresh game, such as venison or wild turkey, is usually leaner than store-bought meat.
Salad with leafy greens and colorful vegetables is a high-fiber, low-calorie choice.
Nuts are regarded as “heart-healthy.” Research suggests walnuts have cardiovascular benefits; pecans, peanuts and other nuts have “good” fats.
Sweet potatoes contain Vitamin A — essential to a strong immune system.
A glass of red wine, which has been found to have a positive effect on cholesterol levels and blood pressure, is less caloric that a glass of eggnog.
The key is moderation, Ms. Sandon said. Eating large portions of even healthy foods can prompt weight gain. Even an extra 150 calories per day – the amount in a 12-ounce soda or a chocolate chip cookie — can add up to a pound of extra weight in about three weeks.
Ms. Sandon offers further tips to help keep pounds from piling up:
Avoid fast food. and set consistent meal times.
Don’t starve all day before a big feast, and you’ll be less likely to overeat.
Eat slowly, and wait a few minutes after one serving to see if you are full.
Socialize away from the buffet table, removing a temptation to overeat.
Bring a low-calorie dish to family feasts.
Food preparation tips
Food preparation can go a long way toward keeping holiday weight off, not to mention preventing food poisoning, Ms. Sandon said.
Here are some calorie-cutting cooking tips:
Use broth to sauté instead of butter — 104 calories saved per tablespoon.
Use nonfat milk instead of whole milk — 60 calories saved per cup.
Use plain, nonfat yogurt instead of cream — 720 calories saved per cup.
Once food is ready, don’t leave it out on the buffet tables for more than two hours. Doing so allows bacteria to build and spurs food-borne illnesses, leading to nausea or worse, Ms. Sandon said.
Also, keep your hands, work surfaces and cooking utensils clean.
Exercising
Exercising regularly is also important for good health, Ms. Sandon said. At least 30 minutes of vigorous physical activity each day is a good rule of thumb, but here are some other tips:
Organize a touch football game during halftime of televised football games.
Arrange holiday-related activities, such as ice-skating or skiing.
Take a walk to see holiday displays.
Walk an extra lap around the mall, even if you’ve finished shopping.
But even a slight weight gain, if left intact, can accumulate yearly and endanger health.
“The problem is in gaining a pound or two and not working it off, even with good intentions and New Year’s resolutions. The gain stays on and adds up each year; in a decade it’s 10 or 20 pounds,” said Lona Sandon, assistant professor of clinical nutrition. “That can lead to obesity and related health problems such as hypertension, stroke, diabetes and other maladies.”
So how can people avoid adding holiday weight?
Healthy food choices, eating habits, food preparation and exercise, Ms. Sandon said.
“First, focus on choosing healthy foods instead of concentrating on what you shouldn’t have,” she said. “For instance, seek out cranberries, which have a high level of antioxidants, which protect cells and help the body block urinary-tract infections and prevent plaque formation on teeth.”
Ms. Sandon listed several other healthy or calorie-saving food choices:
Fresh game, such as venison or wild turkey, is usually leaner than store-bought meat.
Salad with leafy greens and colorful vegetables is a high-fiber, low-calorie choice.
Nuts are regarded as “heart-healthy.” Research suggests walnuts have cardiovascular benefits; pecans, peanuts and other nuts have “good” fats.
Sweet potatoes contain Vitamin A — essential to a strong immune system.
A glass of red wine, which has been found to have a positive effect on cholesterol levels and blood pressure, is less caloric that a glass of eggnog.
The key is moderation, Ms. Sandon said. Eating large portions of even healthy foods can prompt weight gain. Even an extra 150 calories per day – the amount in a 12-ounce soda or a chocolate chip cookie — can add up to a pound of extra weight in about three weeks.
Ms. Sandon offers further tips to help keep pounds from piling up:
Avoid fast food. and set consistent meal times.
Don’t starve all day before a big feast, and you’ll be less likely to overeat.
Eat slowly, and wait a few minutes after one serving to see if you are full.
Socialize away from the buffet table, removing a temptation to overeat.
Bring a low-calorie dish to family feasts.
Food preparation tips
Food preparation can go a long way toward keeping holiday weight off, not to mention preventing food poisoning, Ms. Sandon said.
Here are some calorie-cutting cooking tips:
Use broth to sauté instead of butter — 104 calories saved per tablespoon.
Use nonfat milk instead of whole milk — 60 calories saved per cup.
Use plain, nonfat yogurt instead of cream — 720 calories saved per cup.
Once food is ready, don’t leave it out on the buffet tables for more than two hours. Doing so allows bacteria to build and spurs food-borne illnesses, leading to nausea or worse, Ms. Sandon said.
Also, keep your hands, work surfaces and cooking utensils clean.
Exercising
Exercising regularly is also important for good health, Ms. Sandon said. At least 30 minutes of vigorous physical activity each day is a good rule of thumb, but here are some other tips:
Organize a touch football game during halftime of televised football games.
Arrange holiday-related activities, such as ice-skating or skiing.
Take a walk to see holiday displays.
Walk an extra lap around the mall, even if you’ve finished shopping.
Acid Reflux Disease Linked to Obesity
New Study May Explain Known Connection Between Obesity And Esophageal Cancer
According to a new article in The American Journal of Gastroenterology, gastroesophageal reflux disease (GRD), more commonly known as, acid reflux, is linked to obesity. Since (GRD) is strongly associated with more serious conditions, such as esophageal ulcers and cancer, weight reduction therapy may be useful in treatment and prevention of these conditions.
“The condition is very common, but previous studies have not been successful at pinpointing risk factors for the condition,” says Douglas Corley, author of the study. “Because we reviewed the results of 20 studies on the subject, we were able to better identify and understand the association between obesity and acid reflux.”
In a nation becoming increasingly aware of the dangers of obesity, this new finding provides yet another reason to discuss weight management with a physician. “We know that an increase in body weight increases the chance of having heartburn and acid reflux, which can increase the risk of esophageal ulcers and cancer,” says Corley. “While we can’t say at this time that weight loss therapy is definitely the solution to this condition, it certainly warrants further research as a treatment.”
According to a new article in The American Journal of Gastroenterology, gastroesophageal reflux disease (GRD), more commonly known as, acid reflux, is linked to obesity. Since (GRD) is strongly associated with more serious conditions, such as esophageal ulcers and cancer, weight reduction therapy may be useful in treatment and prevention of these conditions.
“The condition is very common, but previous studies have not been successful at pinpointing risk factors for the condition,” says Douglas Corley, author of the study. “Because we reviewed the results of 20 studies on the subject, we were able to better identify and understand the association between obesity and acid reflux.”
In a nation becoming increasingly aware of the dangers of obesity, this new finding provides yet another reason to discuss weight management with a physician. “We know that an increase in body weight increases the chance of having heartburn and acid reflux, which can increase the risk of esophageal ulcers and cancer,” says Corley. “While we can’t say at this time that weight loss therapy is definitely the solution to this condition, it certainly warrants further research as a treatment.”
Older men treated for early prostate cancer live longer
Older men treated for early prostate cancer live longer than those who are not
An observational study published in JAMA finds men who were treated 31 percent less likely to die
Recent findings from an observational study by researchers at the University of Pennsylvania School of Medicine suggest that men between 65 and 80 years of age who received treatment for early stage, localized prostate cancer lived significantly longer than men who did not receive treatment. The study will be published in the December 13th issue of the Journal of the American Medical Association.
Thanks to better cancer prevention education and the resulting wide-spread increase in using prostate-specific antigen (PSA) screenings, more men are being diagnosed with early-stage and low-or intermediate-grade prostate cancer. Studies have shown that the slow-developing nature of prostate cancer during its earliest stages makes treatment options, such as a radical prostatectomy (surgical removal of the prostate) and radiation therapy, controversial with unpredictable outcomes. Often, recently diagnosed men of this group were advised to just "watch and wait" to see how their situation progressed.
"For this study we looked back over the existing data of a large population of prostate cancer patients, aged 65 to 80, with small tumors that were at a low or intermediate risk of spreading," said senior author Katrina Armstrong, MD, MSCE, who worked on the study with colleagues from Penn's Abramson Cancer Center, Center for Clinical Epidemiology and Biostatistics, Leonard Davis Institute of Health and Economics, and Division of Internal Medicine, and Fox Chase Cancer Center. "After accounting for all their differences, we discovered that the men – who within six months of diagnosis underwent surgery or radiation therapy – were 31 percent less likely to die than those who did not undergo treatment during that time."
Researchers acquired the necessary data for this study from the Surveillance, Epidemiology, and End Results (SEER) Medicare database, a population-based cancer registry which encompasses approximately 14 percent of the US population. Data was included on 44,630 men, aged 65 to 80, who were diagnosed between 1991-1999, with prostate cancer and had survived more than a year after diagnosis. All patients were followed-up until death or December 31st, 2002, the end of the study. Of the 44,630 men, 32,022 (71.8 percent) were actively treated with either surgery or radiation therapy during the first six months after diagnosis. The remaining group of 12,608 (28.3 percent) were classified as having received "observation" and did not undergo surgery, radiation or hormonal therapy.
During the 12-years of follow-up, researchers found that the patients who received treatment had a 31 percent lower risk of death. In the observation-only group, 37 percent of the patients died whereas only 23.8 percent of those in the treatment group died.
Since this was not a randomized, controlled study but a retrospective analysis of existing data, the researches had to perform extensive statistical adjustments to account for study participants differences. Even with all these differences taken into account, there was still a significant improvement in the overall survival of those men who received active treatment. "This benefit was also seen across the board in all subgroups examined, including African-American men and older men aged 75-80 at diagnosis," added Armstrong. "However, as we summarized in the study, because observational data can never completely adjust for potential selection bias and confounding, our results must be validated by rigorous randomized controlled trials of elderly men with localized prostate cancer before the findings can be used to influence treatment decisions."
An observational study published in JAMA finds men who were treated 31 percent less likely to die
Recent findings from an observational study by researchers at the University of Pennsylvania School of Medicine suggest that men between 65 and 80 years of age who received treatment for early stage, localized prostate cancer lived significantly longer than men who did not receive treatment. The study will be published in the December 13th issue of the Journal of the American Medical Association.
Thanks to better cancer prevention education and the resulting wide-spread increase in using prostate-specific antigen (PSA) screenings, more men are being diagnosed with early-stage and low-or intermediate-grade prostate cancer. Studies have shown that the slow-developing nature of prostate cancer during its earliest stages makes treatment options, such as a radical prostatectomy (surgical removal of the prostate) and radiation therapy, controversial with unpredictable outcomes. Often, recently diagnosed men of this group were advised to just "watch and wait" to see how their situation progressed.
"For this study we looked back over the existing data of a large population of prostate cancer patients, aged 65 to 80, with small tumors that were at a low or intermediate risk of spreading," said senior author Katrina Armstrong, MD, MSCE, who worked on the study with colleagues from Penn's Abramson Cancer Center, Center for Clinical Epidemiology and Biostatistics, Leonard Davis Institute of Health and Economics, and Division of Internal Medicine, and Fox Chase Cancer Center. "After accounting for all their differences, we discovered that the men – who within six months of diagnosis underwent surgery or radiation therapy – were 31 percent less likely to die than those who did not undergo treatment during that time."
Researchers acquired the necessary data for this study from the Surveillance, Epidemiology, and End Results (SEER) Medicare database, a population-based cancer registry which encompasses approximately 14 percent of the US population. Data was included on 44,630 men, aged 65 to 80, who were diagnosed between 1991-1999, with prostate cancer and had survived more than a year after diagnosis. All patients were followed-up until death or December 31st, 2002, the end of the study. Of the 44,630 men, 32,022 (71.8 percent) were actively treated with either surgery or radiation therapy during the first six months after diagnosis. The remaining group of 12,608 (28.3 percent) were classified as having received "observation" and did not undergo surgery, radiation or hormonal therapy.
During the 12-years of follow-up, researchers found that the patients who received treatment had a 31 percent lower risk of death. In the observation-only group, 37 percent of the patients died whereas only 23.8 percent of those in the treatment group died.
Since this was not a randomized, controlled study but a retrospective analysis of existing data, the researches had to perform extensive statistical adjustments to account for study participants differences. Even with all these differences taken into account, there was still a significant improvement in the overall survival of those men who received active treatment. "This benefit was also seen across the board in all subgroups examined, including African-American men and older men aged 75-80 at diagnosis," added Armstrong. "However, as we summarized in the study, because observational data can never completely adjust for potential selection bias and confounding, our results must be validated by rigorous randomized controlled trials of elderly men with localized prostate cancer before the findings can be used to influence treatment decisions."
Look For New Natural Sugar Substitute
The California Dental Hygienists' Association (CDHA) recommends consumers be sure to check labels for a natural sugar substitute called xylitol, an important breakthrough in preventing cavities.
Xylitol - a natural sugar substitute that is derived most commonly from birch trees and corn stock - is increasingly being used in candy, gum, toothpaste and mouthwash. It can make a difference in the oral health of every member of a family because xylitol's molecular make up is different than that of traditional sugars so it does not foster an environment necessary for bacteria to decay teeth.
"The holiday season is prime time for tooth decay," said Susan McLearan, CDHA's president. "As dental hygienists we want to raise awareness about an exciting new alternative to traditional sugars and artificial sweeteners."
Studies of xylitol have shown that it can even help repair teeth by stimulating the re-mineralization of teeth already affect by cavities. It also inhibits the further growth of bacteria in the mouth, is low calorie and is safe for diabetics.
In 2005, the U.S. Food and Drug Administration approved the product as a dental caries and periodontal disease preventive. The agency recommends it be used two to three times daily so that the mouth and body are exposed to about 10 grams, chewing the gum or suck the mints for at least five minutes. Xylitol in every stocking can help prevent the spread of this contagious disease dental caries.
Dental caries can be spread from person to person as families share simple items such as spoons. When combined with proper oral hygiene and regular dental care, the use of xylitol products can significantly reduce the risk of cavities and gum infections.
One final note: Do not take in more than 40 grams of xylitol at a time as it can create bowel problems. Also, do not put xylitol in your pet's stockings. Just like chocolate, pets cannot process the product.
Xylitol - a natural sugar substitute that is derived most commonly from birch trees and corn stock - is increasingly being used in candy, gum, toothpaste and mouthwash. It can make a difference in the oral health of every member of a family because xylitol's molecular make up is different than that of traditional sugars so it does not foster an environment necessary for bacteria to decay teeth.
"The holiday season is prime time for tooth decay," said Susan McLearan, CDHA's president. "As dental hygienists we want to raise awareness about an exciting new alternative to traditional sugars and artificial sweeteners."
Studies of xylitol have shown that it can even help repair teeth by stimulating the re-mineralization of teeth already affect by cavities. It also inhibits the further growth of bacteria in the mouth, is low calorie and is safe for diabetics.
In 2005, the U.S. Food and Drug Administration approved the product as a dental caries and periodontal disease preventive. The agency recommends it be used two to three times daily so that the mouth and body are exposed to about 10 grams, chewing the gum or suck the mints for at least five minutes. Xylitol in every stocking can help prevent the spread of this contagious disease dental caries.
Dental caries can be spread from person to person as families share simple items such as spoons. When combined with proper oral hygiene and regular dental care, the use of xylitol products can significantly reduce the risk of cavities and gum infections.
One final note: Do not take in more than 40 grams of xylitol at a time as it can create bowel problems. Also, do not put xylitol in your pet's stockings. Just like chocolate, pets cannot process the product.
Monday, December 11, 2006
Alcohol and health: 2 glasses a day lengthen your life
Alcohol and health: 2 glasses a day lengthen your life
A new study provides further evidence that alcohol, when consumed in moderation, reduces the risk of death, and not just that due to cardiovascular disease
A study performed by the Research Laboratories of the Catholic University of Campobasso (Italy) confirms the beneficial effects that moderate consumption of alcohol has on our health. But this time it is not just cardiovascular disease that gets advantage from this: drinking in moderation reduces all-cause mortality.
The research, published on the American journal Archives of Internal Medicine, assembled 34 scientific studies conducted during the last years worldwide using the statistic procedure of meta-analysis, that al-lows to match different studies to achieve general results. In this way it has been possible to examine data concerning over a million of people, for which alcohol drinking habits were associated with all-cause mortality.
The conclusions researchers from the Catholic University of Campobasso came to clearly show that drinking in moderation (a couple of wine or beer glasses a day) has beneficial effects on health. But that is not all: while the greatest part of the studies conducted on this issue have looked at cardiovascular disease, a term that includes clinical events of various severity, the study published on the Archives of Internal Medicine shows a positive effect of alcohol on an unquestionably hard parameter as overall mortality.
"Our data" says Augusto Di Castelnuovo, lead author of the study, "show that consumption of little amounts of alcohol leads to a reduction of mortality up to 18%. But after a certain number of glasses things radically change: who drinks too much not only looses this advantage, but increases his own risk of death in relation to the amount of alcohol consumed".
The study shows very important differences between men and women. Whereas men report a beneficial effect after consuming 2-4 doses maximum (a dose refers to one glass of wine or beer), women should be aware: for them, the protection guaranteed from alcohol consumption disappears just after two glasses a day.
"It might be- says Licia Iacoviello, Head of the Laboratory of Genetic and Environmental Epidemiology, where the research has been performed- "a fact linked to the metabolism. We know that women metabolize alcohol in a different way and the blood concentration reaches higher levels. Therefore, consuming more than two doses might lead to several harmful effects, such as liver diseases or increased risk of certain forms of tumour".
The meta- analysis conducted by the Catholic University found that the protection given by a moderate consumption of alcohol for American men is lower than the one observed for Europeans. For women, instead, the situation is substantially the same both in USA and Europe. An explanation might be found in the different ways in consuming alcohol. Europeans are more inclined to drink wine rather than other beverages and use to do it while having meals. Two habits different from Americans’. In relation to women, the way they consume alcohol is roughly the same in both continents, thus they respond identically. However, the debate is still open and more research is needed.
Another significant data emerging from the study is related to the so called "confounding factors". During the past years, it has been thought that the protecting effect of alcohol might be ascribed to other factors. It might be, in fact, that people enjoying alcohol drinks in moderation are more concerned about their own health: it may turn out that they are more likely to do sport or to consume healthier food.
In other words it might be that they have a better lifestyle and this could be the cause, not necessarily alcohol, that keeps them in good health.
"We’ve carefully examined this aspect," Di Castelnuovo continues. "Our data suggest that, even considering all main confounding factors (as dietary habits, physical activity or the health of people studied), a moderate consumption of alcoholic beverages keeps on showing a real positive effect".
"The core of this study is not just about alcohol"- says Giovanni de Gaetano, director of the Research Laboratories at the Catholic University- "it is also the way we drink that makes the difference: little amounts, preferably during meals, this appears to be the right way. This is another feature of the Mediterranean diet, where alcohol, wine above all, is the ideal partner of a dinner or lunch, but that’s all: the rest of the day must be absolutely alcohol- free. The message carried by scientific studies like ours is simple: alcohol can be a respectful guest on our table, but it is good just when it goes with a healthy lifestyle, where moderation leads us toward a consumption inspired by quality not by quantity".
A new study provides further evidence that alcohol, when consumed in moderation, reduces the risk of death, and not just that due to cardiovascular disease
A study performed by the Research Laboratories of the Catholic University of Campobasso (Italy) confirms the beneficial effects that moderate consumption of alcohol has on our health. But this time it is not just cardiovascular disease that gets advantage from this: drinking in moderation reduces all-cause mortality.
The research, published on the American journal Archives of Internal Medicine, assembled 34 scientific studies conducted during the last years worldwide using the statistic procedure of meta-analysis, that al-lows to match different studies to achieve general results. In this way it has been possible to examine data concerning over a million of people, for which alcohol drinking habits were associated with all-cause mortality.
The conclusions researchers from the Catholic University of Campobasso came to clearly show that drinking in moderation (a couple of wine or beer glasses a day) has beneficial effects on health. But that is not all: while the greatest part of the studies conducted on this issue have looked at cardiovascular disease, a term that includes clinical events of various severity, the study published on the Archives of Internal Medicine shows a positive effect of alcohol on an unquestionably hard parameter as overall mortality.
"Our data" says Augusto Di Castelnuovo, lead author of the study, "show that consumption of little amounts of alcohol leads to a reduction of mortality up to 18%. But after a certain number of glasses things radically change: who drinks too much not only looses this advantage, but increases his own risk of death in relation to the amount of alcohol consumed".
The study shows very important differences between men and women. Whereas men report a beneficial effect after consuming 2-4 doses maximum (a dose refers to one glass of wine or beer), women should be aware: for them, the protection guaranteed from alcohol consumption disappears just after two glasses a day.
"It might be- says Licia Iacoviello, Head of the Laboratory of Genetic and Environmental Epidemiology, where the research has been performed- "a fact linked to the metabolism. We know that women metabolize alcohol in a different way and the blood concentration reaches higher levels. Therefore, consuming more than two doses might lead to several harmful effects, such as liver diseases or increased risk of certain forms of tumour".
The meta- analysis conducted by the Catholic University found that the protection given by a moderate consumption of alcohol for American men is lower than the one observed for Europeans. For women, instead, the situation is substantially the same both in USA and Europe. An explanation might be found in the different ways in consuming alcohol. Europeans are more inclined to drink wine rather than other beverages and use to do it while having meals. Two habits different from Americans’. In relation to women, the way they consume alcohol is roughly the same in both continents, thus they respond identically. However, the debate is still open and more research is needed.
Another significant data emerging from the study is related to the so called "confounding factors". During the past years, it has been thought that the protecting effect of alcohol might be ascribed to other factors. It might be, in fact, that people enjoying alcohol drinks in moderation are more concerned about their own health: it may turn out that they are more likely to do sport or to consume healthier food.
In other words it might be that they have a better lifestyle and this could be the cause, not necessarily alcohol, that keeps them in good health.
"We’ve carefully examined this aspect," Di Castelnuovo continues. "Our data suggest that, even considering all main confounding factors (as dietary habits, physical activity or the health of people studied), a moderate consumption of alcoholic beverages keeps on showing a real positive effect".
"The core of this study is not just about alcohol"- says Giovanni de Gaetano, director of the Research Laboratories at the Catholic University- "it is also the way we drink that makes the difference: little amounts, preferably during meals, this appears to be the right way. This is another feature of the Mediterranean diet, where alcohol, wine above all, is the ideal partner of a dinner or lunch, but that’s all: the rest of the day must be absolutely alcohol- free. The message carried by scientific studies like ours is simple: alcohol can be a respectful guest on our table, but it is good just when it goes with a healthy lifestyle, where moderation leads us toward a consumption inspired by quality not by quantity".
Diets may lead to bone loss
Men and women who lose weight by cutting calories also may be losing bone density, but weight loss through exercise does not seem to produce the same effect, according to a report in the December 11/25 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Most U.S. adults are either overweight or obese, according to background information in the article. The primary treatment for these conditions is lifestyle modification, including exercise and low-calorie diets. However, decreasing body weight is associated with decreased bone mineral density, which increases the risk for osteoporosis (weakening of the bones) and hip fractures in older men and women.
Dennis T. Villareal, M.D., Washington University School of Medicine, St. Louis, and colleagues studied the effects of weight loss on bone loss in 48 adults (30 women and 18 men, with an average age of 57). Nineteen were assigned to follow a calorie-restricted diet (to decrease energy intake by 16 percent for three months, then by 20 percent for nine months), 19 to eat the same number of calories and begin an exercise program (to maintain energy intake, but increase energy expenditure by 16 percent for three months and 20 percent for nine months) and 10 to receive information on healthy lifestyles only when requested. All participants were weighed at the beginning of the study and again after one, three, six, nine and 12 months. Bone mineral density was measured every three months using a technique known as dual-energy x-ray absorptiometry. At the start of the study and after six months and 12 months, blood samples were taken to test for hormones and chemical markers that show whether bone tissue is being absorbed and regenerated.
Forty-six of the participants completed the study. After one year, those in the calorie restriction group lost an average of 8.2 kilograms or 18.1 pounds, those in the exercise intervention group lost 6.7 kilograms or 14.8 pounds and those in the healthy lifestyle group maintained their weight. Individuals in the calorie-restriction group also lost an average of 2.2 percent of their bone density in the lower spine, 2.2 percent at the hip and 2.1 percent at the top end of the femur—all high-risk fracture sites. There were no significant changes in bone mineral density in the exercise or healthy lifestyle groups. In both weight-loss groups, bone turnover—which occurs when old bone is broken down—increased, as indicated by the markers of bone turnover in the blood.
"A common explanation given for the bone loss induced by weight loss is reduction in mechanical stress on the weight-bearing skeleton (i.e., hip and spine)," the authors write. "Accordingly, the preservation of bone mineral density in the exercise group could be mediated through exercise-induced bone loading." In addition, although both weight-loss groups experienced an increase in bone turnover, this was only detrimental to the calorie restriction group. Muscles pulling on bones during exercise is thought to produce strains in the skeleton that stimulate new bone production. "Our results are consistent with an osteoprotective effect of exercise-induced mechanical strain on the skeleton and consequent increase in bone turnover," the authors continue.
"These findings have important implications in designing an appropriate weight-loss therapy program in middle-aged adults, particularly in the subset of patients who may already be at increased risk for bone fracture," they conclude.
Most U.S. adults are either overweight or obese, according to background information in the article. The primary treatment for these conditions is lifestyle modification, including exercise and low-calorie diets. However, decreasing body weight is associated with decreased bone mineral density, which increases the risk for osteoporosis (weakening of the bones) and hip fractures in older men and women.
Dennis T. Villareal, M.D., Washington University School of Medicine, St. Louis, and colleagues studied the effects of weight loss on bone loss in 48 adults (30 women and 18 men, with an average age of 57). Nineteen were assigned to follow a calorie-restricted diet (to decrease energy intake by 16 percent for three months, then by 20 percent for nine months), 19 to eat the same number of calories and begin an exercise program (to maintain energy intake, but increase energy expenditure by 16 percent for three months and 20 percent for nine months) and 10 to receive information on healthy lifestyles only when requested. All participants were weighed at the beginning of the study and again after one, three, six, nine and 12 months. Bone mineral density was measured every three months using a technique known as dual-energy x-ray absorptiometry. At the start of the study and after six months and 12 months, blood samples were taken to test for hormones and chemical markers that show whether bone tissue is being absorbed and regenerated.
Forty-six of the participants completed the study. After one year, those in the calorie restriction group lost an average of 8.2 kilograms or 18.1 pounds, those in the exercise intervention group lost 6.7 kilograms or 14.8 pounds and those in the healthy lifestyle group maintained their weight. Individuals in the calorie-restriction group also lost an average of 2.2 percent of their bone density in the lower spine, 2.2 percent at the hip and 2.1 percent at the top end of the femur—all high-risk fracture sites. There were no significant changes in bone mineral density in the exercise or healthy lifestyle groups. In both weight-loss groups, bone turnover—which occurs when old bone is broken down—increased, as indicated by the markers of bone turnover in the blood.
"A common explanation given for the bone loss induced by weight loss is reduction in mechanical stress on the weight-bearing skeleton (i.e., hip and spine)," the authors write. "Accordingly, the preservation of bone mineral density in the exercise group could be mediated through exercise-induced bone loading." In addition, although both weight-loss groups experienced an increase in bone turnover, this was only detrimental to the calorie restriction group. Muscles pulling on bones during exercise is thought to produce strains in the skeleton that stimulate new bone production. "Our results are consistent with an osteoprotective effect of exercise-induced mechanical strain on the skeleton and consequent increase in bone turnover," the authors continue.
"These findings have important implications in designing an appropriate weight-loss therapy program in middle-aged adults, particularly in the subset of patients who may already be at increased risk for bone fracture," they conclude.
Prevent cancer, use olive oil
Innovative research article in the FASEB Journal suggests olive oil has a significant impact on cancer rates.
If you want to avoid developing cancer, then you might want to add eating more olive oil to your list of New Year's resolutions. In a study to be published in the January 2007 issue of The FASEB Journal, scientists from five European countries describe how the anti-cancer effects of olive oil may account for the significant difference in cancer rates among Northern and Southern Europeans.
The authors drew this conclusion based on the outcomes of volunteers from Denmark, Finland, Germany, Italy, and Spain, who consumed 25 milliliters (a little less than a quarter cup) of olive oil every day for three weeks. During this time, the researchers examined urine samples of the subjects for specific compounds known to be waste by-products of oxidative damage to cells, a precursor to cancer. At the beginning of the trial, the presence of these waste by-products was much higher in Northern European subjects than their Southern European counterparts. By the end of three weeks, however, the presence of this compound in Northern European subjects was substantially reduced.
"Determining the health benefits of any particular food is challenging because of it involves relatively large numbers of people over significant periods of time," said lead investigator Henrik E. Poulsen, M.D. of Rigshospitalet, Denmark. "In our study, we overcame these challenges by measuring how olive oil affected the oxidation of our genes, which is closely linked to development of disease. This approach allows us to determine if olive oil or any other food makes a difference. Our findings must be confirmed, but every piece of evidence so far points to olive oil being a healthy food. By the way, it also tastes great."
Another interesting finding in the study suggests that researchers are just beginning to unlock the mysteries of this ancient "health food." Specifically, the researchers found evidence that the phenols in olive oil are not the only compounds that reduced oxidative damage. Phenols are known antioxidant compounds that are present in a wide range of everyday foods, such as dark chocolate, red wine, tea, fruits, and vegetables. Despite reducing the level of phenols in the olive oil, the study's subjects still showed that they were receiving the same level of health benefits.
"Every New Year people make resolutions that involve eating less fat to improve their health," said Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal. "This academically sound, practically useful study shows that what you eat is just as important as how much you eat. No wonder Plato taught wisdom in an olive grove called Academe."
If you want to avoid developing cancer, then you might want to add eating more olive oil to your list of New Year's resolutions. In a study to be published in the January 2007 issue of The FASEB Journal, scientists from five European countries describe how the anti-cancer effects of olive oil may account for the significant difference in cancer rates among Northern and Southern Europeans.
The authors drew this conclusion based on the outcomes of volunteers from Denmark, Finland, Germany, Italy, and Spain, who consumed 25 milliliters (a little less than a quarter cup) of olive oil every day for three weeks. During this time, the researchers examined urine samples of the subjects for specific compounds known to be waste by-products of oxidative damage to cells, a precursor to cancer. At the beginning of the trial, the presence of these waste by-products was much higher in Northern European subjects than their Southern European counterparts. By the end of three weeks, however, the presence of this compound in Northern European subjects was substantially reduced.
"Determining the health benefits of any particular food is challenging because of it involves relatively large numbers of people over significant periods of time," said lead investigator Henrik E. Poulsen, M.D. of Rigshospitalet, Denmark. "In our study, we overcame these challenges by measuring how olive oil affected the oxidation of our genes, which is closely linked to development of disease. This approach allows us to determine if olive oil or any other food makes a difference. Our findings must be confirmed, but every piece of evidence so far points to olive oil being a healthy food. By the way, it also tastes great."
Another interesting finding in the study suggests that researchers are just beginning to unlock the mysteries of this ancient "health food." Specifically, the researchers found evidence that the phenols in olive oil are not the only compounds that reduced oxidative damage. Phenols are known antioxidant compounds that are present in a wide range of everyday foods, such as dark chocolate, red wine, tea, fruits, and vegetables. Despite reducing the level of phenols in the olive oil, the study's subjects still showed that they were receiving the same level of health benefits.
"Every New Year people make resolutions that involve eating less fat to improve their health," said Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal. "This academically sound, practically useful study shows that what you eat is just as important as how much you eat. No wonder Plato taught wisdom in an olive grove called Academe."
Saturday, December 9, 2006
Mind Controls Pain, Instruments
The term "mind control" has an ominous, Orwellian ring to it. But when it's the owner of the mind at the controls, the benefits can be tremendous, as two groups of researchers showed this past year.
Sean Mackey, MD, PhD, assistant professor of anesthesia, used the power of a new technology called real-time functional magnetic resonance imaging, or rtfMRI, to help patients learn to reduce their own pain.
Subjects were placed inside an MRI scanner where they were able to watch their brain activity. They were then shown "live" action images of an area of the brain responsible for processing pain, and given various mental strategies to try to alter their brain activity.
"As an example, we asked them to think about changing the meaning of the pain," Mackey said. "Instead of thinking of it as a terrible experience, to think of it as something relatively pleasant. Over time, subjects showed an increased ability to change their brain and by doing so to modulate their pain."
Mackey said more studies still have to be done to see if the method holds up.
Another brainy advance came from Krishna Shenoy, PhD, assistant professor of electrical engineering and of neuroscience. His work brought a long-standing science fiction concept — the idea of a disembodied brain linked to a computer apparatus by which it controls the world — one step closer to reality.
Actually, Shenoy has a more humanitarian aim: helping paralyzed people interact with the world around them. He and his team of researchers used a prosthesis called a brain-computer interface — consisting of electrodes attached to a subject's head — to record brain waves. The device then sends the signals to a computer, which translates them into commands to control the prosthesis.
A big barrier to making such prostheses practical has been the slowness of translating signals into action. Shenoy's team developed a new algorithm that quadrupled the processing speed. The group published its results this year. Shenoy said that his team's work — done with rhesus macaque monkeys — coupled with advances from other researchers working with human subjects, shows it will be possible to devise a truly functional prosthesis for the paralyzed.
Sean Mackey, MD, PhD, assistant professor of anesthesia, used the power of a new technology called real-time functional magnetic resonance imaging, or rtfMRI, to help patients learn to reduce their own pain.
Subjects were placed inside an MRI scanner where they were able to watch their brain activity. They were then shown "live" action images of an area of the brain responsible for processing pain, and given various mental strategies to try to alter their brain activity.
"As an example, we asked them to think about changing the meaning of the pain," Mackey said. "Instead of thinking of it as a terrible experience, to think of it as something relatively pleasant. Over time, subjects showed an increased ability to change their brain and by doing so to modulate their pain."
Mackey said more studies still have to be done to see if the method holds up.
Another brainy advance came from Krishna Shenoy, PhD, assistant professor of electrical engineering and of neuroscience. His work brought a long-standing science fiction concept — the idea of a disembodied brain linked to a computer apparatus by which it controls the world — one step closer to reality.
Actually, Shenoy has a more humanitarian aim: helping paralyzed people interact with the world around them. He and his team of researchers used a prosthesis called a brain-computer interface — consisting of electrodes attached to a subject's head — to record brain waves. The device then sends the signals to a computer, which translates them into commands to control the prosthesis.
A big barrier to making such prostheses practical has been the slowness of translating signals into action. Shenoy's team developed a new algorithm that quadrupled the processing speed. The group published its results this year. Shenoy said that his team's work — done with rhesus macaque monkeys — coupled with advances from other researchers working with human subjects, shows it will be possible to devise a truly functional prosthesis for the paralyzed.
Friday, December 8, 2006
Is Caffeine Addictive? A Review of the Literature
Abstract
The common-sense use of the term addiction is that regular consumption is irresistible and that it creates problems. Caffeine use does not fit this profile. Its intake does no harm to the individual or to society, and its users are not compelled to consume it. Though cessation of regular use may result in symptoms such as headache and lethargy, these are easily and reliably reversed by ingestion of caffeine. Some have argued that continued caffeine use is an attempt to suppress low grade withdrawal symptoms such as sleepiness and lethargy. In some moderate users, this is possible; however, in experimental contexts, the phenomenon is too inconsistent to constitute a reliably valid syndrome.
Click here to view the complete essay as an Adobe Acrobat PDF.
The common-sense use of the term addiction is that regular consumption is irresistible and that it creates problems. Caffeine use does not fit this profile. Its intake does no harm to the individual or to society, and its users are not compelled to consume it. Though cessation of regular use may result in symptoms such as headache and lethargy, these are easily and reliably reversed by ingestion of caffeine. Some have argued that continued caffeine use is an attempt to suppress low grade withdrawal symptoms such as sleepiness and lethargy. In some moderate users, this is possible; however, in experimental contexts, the phenomenon is too inconsistent to constitute a reliably valid syndrome.
Click here to view the complete essay as an Adobe Acrobat PDF.
How to Cut Down on 'Mindless Eating'
How to cut down on high-fat 'mindless eating' is the focus of Cornell professor's new book.
The average person makes more than 200 food-related decisions every day, day in and day out -- yet isn't aware of 90 percent of them, says Cornell marketing professor Brian Wansink in his new book, "Mindless Eating: Why We Eat More Than We Think" (Bantam Books).
We eat not to satisfy hunger so much, he says, but as a mindless response to cues and signals to eat.
Huge portions, oversized plates, all-night restaurants, bowls of tempting foods in full view, eating on the run or at the desk while multitasking are just a few of the mindless-eating pitfalls detailed in the book.
"We overeat because there are signals and cues around us that tell us to eat. It's simply not in our nature to pause after every bite and contemplate whether we're full," Wansink writes in his first chapter, noting that if the cues are right, we'll even eat cold, limp, soggy and stale food.
"For many of us, as long as there are still a few milk-soaked Froot Loops left at the bottom of the cereal bowl, there is still work to be done. It doesn't matter if we're full, and it doesn't matter if we don't really like what we're eating. We eat as if it is our mission to finish them."
Wansink is the John S. Dyson Professor of Marketing in the Department of Applied Economics and Management at Cornell and director of the Cornell Food and Brand Lab, staffed by interdisciplinary researchers who have conducted more than 200 studies on the psychology behind what people eat and how often they eat it.
His book, written for the lay audience, not only features numerous drawings, charts and boxes but also a multitude of tips on how to become a more mindful eater, which should automatically help consumers slim down without dieting.
Among his many suggestions:
Don't keep tempting foods out in full view but put them in inconvenient places.
Don't use oversized dishes, glasses and bowls.
Beware of the "health halo": When eating food tagged as "low fat," don't reward yourself by adding a host of high-calorie extras.
Use such "restaurant rules" as sitting next to the slowest eater, being the last person to start eating, setting your fork down after every bite and always sharing a dessert, keeping in mind that the first two bites are the best.
Don't deprive yourself -- just eat comfort foods in smaller amounts.
After all, "The best diet is the one you don't know you're on," says Wansink, emphasizing that making small changes can reap big results in the long term.
The average person makes more than 200 food-related decisions every day, day in and day out -- yet isn't aware of 90 percent of them, says Cornell marketing professor Brian Wansink in his new book, "Mindless Eating: Why We Eat More Than We Think" (Bantam Books).
We eat not to satisfy hunger so much, he says, but as a mindless response to cues and signals to eat.
Huge portions, oversized plates, all-night restaurants, bowls of tempting foods in full view, eating on the run or at the desk while multitasking are just a few of the mindless-eating pitfalls detailed in the book.
"We overeat because there are signals and cues around us that tell us to eat. It's simply not in our nature to pause after every bite and contemplate whether we're full," Wansink writes in his first chapter, noting that if the cues are right, we'll even eat cold, limp, soggy and stale food.
"For many of us, as long as there are still a few milk-soaked Froot Loops left at the bottom of the cereal bowl, there is still work to be done. It doesn't matter if we're full, and it doesn't matter if we don't really like what we're eating. We eat as if it is our mission to finish them."
Wansink is the John S. Dyson Professor of Marketing in the Department of Applied Economics and Management at Cornell and director of the Cornell Food and Brand Lab, staffed by interdisciplinary researchers who have conducted more than 200 studies on the psychology behind what people eat and how often they eat it.
His book, written for the lay audience, not only features numerous drawings, charts and boxes but also a multitude of tips on how to become a more mindful eater, which should automatically help consumers slim down without dieting.
Among his many suggestions:
Don't keep tempting foods out in full view but put them in inconvenient places.
Don't use oversized dishes, glasses and bowls.
Beware of the "health halo": When eating food tagged as "low fat," don't reward yourself by adding a host of high-calorie extras.
Use such "restaurant rules" as sitting next to the slowest eater, being the last person to start eating, setting your fork down after every bite and always sharing a dessert, keeping in mind that the first two bites are the best.
Don't deprive yourself -- just eat comfort foods in smaller amounts.
After all, "The best diet is the one you don't know you're on," says Wansink, emphasizing that making small changes can reap big results in the long term.
Thursday, December 7, 2006
Not ready to quit? Try cutting back
In a review article in the December Nicotine and Tobacco Research, researchers at the University of Vermont have found an unexpected, effective alternative to motivate smokers to quit smoking – cutting back. According to the qualitative review of 19 studies on smoking reduction in individuals who did not want to quit, this method, typically coupled with the use of nicotine replacement products, led to an increase in quitting in 16 of the studies.
"Cutting back is approved as a method of quitting in several European countries, but not in the United States," said lead author John Hughes, M.D., a professor of psychiatry at the University of Vermont College of Medicine. "Our review contradicts the commonly held belief that quitting requires stopping abruptly and provides evidence that smokers can quit successfully by reducing the amount of cigarettes smoked. Furthermore, our review indicates cutting back is often a great way to start changing smoking that can lead to eventual quitting."
Hughes's report is the largest review of smoking reduction studies published to date. Among the 19 studies reviewed (many of which were randomized, placebo-controlled trials), the two considered the most important involved randomized, controlled trials that assigned smokers to either reduce or not reduce. Both of these studies found that smoking reduction leads to more cessation. Also, in three studies, the effect of reduction was found to be similar to the effect of providing smoking cessation advice. Based on this finding, Hughes suggests that clinicians try recommending reduction for smokers who have not responded to repeated cessation advice.
Hughes and colleague Matthew Carpenter warn that smokers do need to understand that there is no good evidence that cutting back alone decreases smoking-related health risks and thus clinicians should promote reduction only as a step towards eventual cessation to their patients.
"Cutting back is approved as a method of quitting in several European countries, but not in the United States," said lead author John Hughes, M.D., a professor of psychiatry at the University of Vermont College of Medicine. "Our review contradicts the commonly held belief that quitting requires stopping abruptly and provides evidence that smokers can quit successfully by reducing the amount of cigarettes smoked. Furthermore, our review indicates cutting back is often a great way to start changing smoking that can lead to eventual quitting."
Hughes's report is the largest review of smoking reduction studies published to date. Among the 19 studies reviewed (many of which were randomized, placebo-controlled trials), the two considered the most important involved randomized, controlled trials that assigned smokers to either reduce or not reduce. Both of these studies found that smoking reduction leads to more cessation. Also, in three studies, the effect of reduction was found to be similar to the effect of providing smoking cessation advice. Based on this finding, Hughes suggests that clinicians try recommending reduction for smokers who have not responded to repeated cessation advice.
Hughes and colleague Matthew Carpenter warn that smokers do need to understand that there is no good evidence that cutting back alone decreases smoking-related health risks and thus clinicians should promote reduction only as a step towards eventual cessation to their patients.
Solitary drug, alcohol and cigarette use puts adolescents at higher risk
Adolescents who use alcohol, cigarettes and marijuana while alone are more likely to have health and behavioral problems as young adults than their peers who consume the substances only in social settings, according to a RAND Corporation study issued today.
Solitary alcohol, cigarette and marijuana users are less likely to graduate from college, more likely to have substance use problems as young adults, and tend to report poorer physical health by age 23 than their peers who were social substance users, according to the study by the nonprofit research organization.
"While substance use is a problem in itself, these findings suggest that risk among solitary users is especially high," said Joan Tucker, a RAND psychologist and lead author of the study. "Solitary use is a warning sign that youth will be less productive and have more problems as young adults -- more problems, even, than others who also used substances during childhood. The challenge is to identify these at-risk children and find out what type of assistance might benefit them."
Among the 8th graders studied, 16 percent had smoked cigarettes while alone, 17 percent had engaged in solitary drinking and 4 percent had used marijuana while alone.
Prior research has found that adolescent substance users are at risk for a wide range of problems during adolescence that persist into young adulthood, such as low academic achievement, stealing and other social problems.
The RAND Health study, published in the December edition of the journal Psychology of Addictive Behaviors, is the first to study adolescent solitary substance users and track their functioning over time.
The results come from a study of about 6,000 adolescents from California and Oregon enrolled in a program to evaluate Project ALERT, a drug use prevention program developed by RAND for middle school children. People involved in the study were asked about their substance use and a variety of other issues several times during middle school and high school, and again at age 23.
Researchers found that during adolescence, those who used alcohol, cigarettes and marijuana alone were at higher risk for a variety of troubling behaviors as compared with social-only users. Solitary users admitted to more delinquent behavior, such as stealing and acting out at school, and were less inclined to talk to their parents about personal problems.
Solitary users also were less engaged with school. This was evidenced by their lower grades, less time spent on homework and less time devoted to school activities. However, solitary users spent significantly more time going to parties and dating than other substance-using youth.
"This dispels the notion that these solitary users are lonely, socially isolated teens," Tucker said.
Consistent with their active social life, solitary substance users typically felt that substance use has positive effects on their behavior, allowing them to relax, have more fun, and get away from their problems. In contrast, they were less likely than social-only users to think substance use is harmful -- that it impairs physical and cognitive functioning, and factors into behavioral problems.
In addition, solitary users reported higher frequency and quantity of substance use compared to social-only users. On average:
Solitary users in 8th grade reported using alcohol, cigarettes or marijuana three to five days in the past month. On the days they used the substances, they smoked three to seven cigarettes, had two to three alcoholic drinks, or smoked marijuana three or more times.
Social-only users in 8th grade reported using substances less than one to two days in the past month. On the days they used the substances, they smoked one to two cigarettes, had one drink, or smoked marijuana twice.
Solitary alcohol, cigarette and marijuana users are less likely to graduate from college, more likely to have substance use problems as young adults, and tend to report poorer physical health by age 23 than their peers who were social substance users, according to the study by the nonprofit research organization.
"While substance use is a problem in itself, these findings suggest that risk among solitary users is especially high," said Joan Tucker, a RAND psychologist and lead author of the study. "Solitary use is a warning sign that youth will be less productive and have more problems as young adults -- more problems, even, than others who also used substances during childhood. The challenge is to identify these at-risk children and find out what type of assistance might benefit them."
Among the 8th graders studied, 16 percent had smoked cigarettes while alone, 17 percent had engaged in solitary drinking and 4 percent had used marijuana while alone.
Prior research has found that adolescent substance users are at risk for a wide range of problems during adolescence that persist into young adulthood, such as low academic achievement, stealing and other social problems.
The RAND Health study, published in the December edition of the journal Psychology of Addictive Behaviors, is the first to study adolescent solitary substance users and track their functioning over time.
The results come from a study of about 6,000 adolescents from California and Oregon enrolled in a program to evaluate Project ALERT, a drug use prevention program developed by RAND for middle school children. People involved in the study were asked about their substance use and a variety of other issues several times during middle school and high school, and again at age 23.
Researchers found that during adolescence, those who used alcohol, cigarettes and marijuana alone were at higher risk for a variety of troubling behaviors as compared with social-only users. Solitary users admitted to more delinquent behavior, such as stealing and acting out at school, and were less inclined to talk to their parents about personal problems.
Solitary users also were less engaged with school. This was evidenced by their lower grades, less time spent on homework and less time devoted to school activities. However, solitary users spent significantly more time going to parties and dating than other substance-using youth.
"This dispels the notion that these solitary users are lonely, socially isolated teens," Tucker said.
Consistent with their active social life, solitary substance users typically felt that substance use has positive effects on their behavior, allowing them to relax, have more fun, and get away from their problems. In contrast, they were less likely than social-only users to think substance use is harmful -- that it impairs physical and cognitive functioning, and factors into behavioral problems.
In addition, solitary users reported higher frequency and quantity of substance use compared to social-only users. On average:
Solitary users in 8th grade reported using alcohol, cigarettes or marijuana three to five days in the past month. On the days they used the substances, they smoked three to seven cigarettes, had two to three alcoholic drinks, or smoked marijuana three or more times.
Social-only users in 8th grade reported using substances less than one to two days in the past month. On the days they used the substances, they smoked one to two cigarettes, had one drink, or smoked marijuana twice.
Does too much protein in the diet increase cancer risk?
A great deal of research connects nutrition with cancer risk. Overweight people are at higher risk of developing post-menopausal breast cancer, endometrial cancer, colon cancer, kidney cancer and a certain type of esophageal cancer. Now preliminary findings from researchers at Washington University School of Medicine in St. Louis suggest that eating less protein may help protect against certain cancers that are not directly associated with obesity.
The research, published in the December issue of the American Journal of Clinical Nutrition, shows that lean people on a long-term, low-protein, low-calorie diet or participating in regular endurance exercise training have lower levels of plasma growth factors and certain hormones linked to cancer risk.
"However, people on a low-protein, low-calorie diet had considerably lower levels of a particular plasma growth factor called IGF-1 than equally lean endurance runners," says the study's first author Luigi Fontana, M.D., Ph.D., assistant professor of medicine at Washington University and an investigator at the Istituto Superiore di Sanità in Rome, Italy. "That suggests to us that a diet lower in protein may have a greater protective effect against cancer than endurance exercise, independently of body fat mass."
The study involved three groups of people. The first ate a low-protein, low-calorie, raw food vegetarian diet and was made up of 21 lean men and women. Another group consisted of 21 lean subjects who did regular endurance running, averaging about 48 miles per week. The runners ate a standard Western diet, consuming more calories and protein than group one. The third group included 21 sedentary people who also consumed a standard Western diet, higher in sugars, processed refined grains and animal products. The subjects were matched for age, sex and other demographic factors, and no one smoked or had diabetes, cardiovascular disease, cancer, lung disease or other chronic illness.
Protein intake was, not surprisingly, lowest in the low-protein group. They averaged a daily intake of 0.73 grams of protein per kilogram of body weight. Endurance runners ate 1.6 grams and sedentary people on the Western diet, 1.23 grams. The recommended daily allowance for protein intake is 0.8 grams. That's about three ounces of protein per day for a 220-pound man.
"It's interesting to us that both the runners and especially the sedentary people consumed about 50 percent more protein than recommended," says Fontana. "We know that if we consume 50 percent more calories than recommended, we will become obese. But there is not a lot of research on whether chronic over-consumption of protein also has harmful effects."
Fontana and colleagues found significantly lower blood levels of plasma insulin-like growth factor 1 (IGF-1) in the low-protein diet group than in either the equally lean runners or the sedentary people eating a standard Western diet. Past research has linked pre-menopausal breast cancer, prostate cancer and certain types of colon cancer to high levels of IGF-1, a powerful growth factor that promotes cell proliferation. Data from animal studies also suggest that lower IGF-1 levels are associated with maximal lifespan.
"Our findings show that in normal weight people IGF-1 levels are related to protein intake, independent of body weight and fat mass," Fontana says. "I believe our findings suggest that protein intake may be very important in regulating cancer risk."
He calls the study a hypothesis-generating paper that suggests connections between dietary protein and epidemiological studies that show associations between IGF-1 levels and the risk of cancer. But he says more research is needed to clarify what that connection is.
The researchers also found that the group of endurance runners in the study consumed the highest number of calories, averaging more than 2,600 per day. Those on a standard Western diet consumed just over 2,300 calories daily, while those in the low-calorie, low-protein group ate just under 2,000 calories a day. Members of the latter group also tended to weigh less than sedentary people but slightly more than the endurance runners. The average body mass index (BMI) in the low-protein, low-calorie group was 21.3. BMI averaged 21.1 among the runners and 26.5 among those who were sedentary. BMI is a measurement of weight divided by height squared. People with a BMI greater than 25 are considered overweight.
Fontana says most of us don't eat nearly enough fruits and vegetables or enough whole-grains, cereals or beans. "Many people are eating too many animal products — such as meat, cheese, eggs and butter — as well as refined grains and free sugars," he says. "Our intake of vegetables and fruits is low, and beans are vastly underconsumed in the U.S. and Europe these days. "
He believes diets would be healthier if we ate more whole grains, beans, fruits and vegetables and far fewer animal products. He recommends mostly fish, low-fat dairy products and, occasionally, some red meat. Such a diet would both cut total calories and reduce the amount of protein we consume to a level closer to the range recommended by the nutrition experts of the Food Nutrition Board of the National Academy of Sciences. It also might result in lower levels of IGF-1.
"Eating too many calories increases our risk of developing obesity, diabetes, cardiovascular disease and of certain types of cancer related to obesity," Fontana says. "We hope to further clarify what happens to cancer risk when we are chronically eating more protein than we need."
The research, published in the December issue of the American Journal of Clinical Nutrition, shows that lean people on a long-term, low-protein, low-calorie diet or participating in regular endurance exercise training have lower levels of plasma growth factors and certain hormones linked to cancer risk.
"However, people on a low-protein, low-calorie diet had considerably lower levels of a particular plasma growth factor called IGF-1 than equally lean endurance runners," says the study's first author Luigi Fontana, M.D., Ph.D., assistant professor of medicine at Washington University and an investigator at the Istituto Superiore di Sanità in Rome, Italy. "That suggests to us that a diet lower in protein may have a greater protective effect against cancer than endurance exercise, independently of body fat mass."
The study involved three groups of people. The first ate a low-protein, low-calorie, raw food vegetarian diet and was made up of 21 lean men and women. Another group consisted of 21 lean subjects who did regular endurance running, averaging about 48 miles per week. The runners ate a standard Western diet, consuming more calories and protein than group one. The third group included 21 sedentary people who also consumed a standard Western diet, higher in sugars, processed refined grains and animal products. The subjects were matched for age, sex and other demographic factors, and no one smoked or had diabetes, cardiovascular disease, cancer, lung disease or other chronic illness.
Protein intake was, not surprisingly, lowest in the low-protein group. They averaged a daily intake of 0.73 grams of protein per kilogram of body weight. Endurance runners ate 1.6 grams and sedentary people on the Western diet, 1.23 grams. The recommended daily allowance for protein intake is 0.8 grams. That's about three ounces of protein per day for a 220-pound man.
"It's interesting to us that both the runners and especially the sedentary people consumed about 50 percent more protein than recommended," says Fontana. "We know that if we consume 50 percent more calories than recommended, we will become obese. But there is not a lot of research on whether chronic over-consumption of protein also has harmful effects."
Fontana and colleagues found significantly lower blood levels of plasma insulin-like growth factor 1 (IGF-1) in the low-protein diet group than in either the equally lean runners or the sedentary people eating a standard Western diet. Past research has linked pre-menopausal breast cancer, prostate cancer and certain types of colon cancer to high levels of IGF-1, a powerful growth factor that promotes cell proliferation. Data from animal studies also suggest that lower IGF-1 levels are associated with maximal lifespan.
"Our findings show that in normal weight people IGF-1 levels are related to protein intake, independent of body weight and fat mass," Fontana says. "I believe our findings suggest that protein intake may be very important in regulating cancer risk."
He calls the study a hypothesis-generating paper that suggests connections between dietary protein and epidemiological studies that show associations between IGF-1 levels and the risk of cancer. But he says more research is needed to clarify what that connection is.
The researchers also found that the group of endurance runners in the study consumed the highest number of calories, averaging more than 2,600 per day. Those on a standard Western diet consumed just over 2,300 calories daily, while those in the low-calorie, low-protein group ate just under 2,000 calories a day. Members of the latter group also tended to weigh less than sedentary people but slightly more than the endurance runners. The average body mass index (BMI) in the low-protein, low-calorie group was 21.3. BMI averaged 21.1 among the runners and 26.5 among those who were sedentary. BMI is a measurement of weight divided by height squared. People with a BMI greater than 25 are considered overweight.
Fontana says most of us don't eat nearly enough fruits and vegetables or enough whole-grains, cereals or beans. "Many people are eating too many animal products — such as meat, cheese, eggs and butter — as well as refined grains and free sugars," he says. "Our intake of vegetables and fruits is low, and beans are vastly underconsumed in the U.S. and Europe these days. "
He believes diets would be healthier if we ate more whole grains, beans, fruits and vegetables and far fewer animal products. He recommends mostly fish, low-fat dairy products and, occasionally, some red meat. Such a diet would both cut total calories and reduce the amount of protein we consume to a level closer to the range recommended by the nutrition experts of the Food Nutrition Board of the National Academy of Sciences. It also might result in lower levels of IGF-1.
"Eating too many calories increases our risk of developing obesity, diabetes, cardiovascular disease and of certain types of cancer related to obesity," Fontana says. "We hope to further clarify what happens to cancer risk when we are chronically eating more protein than we need."
Smoking worsens knee osteoarthritis
New findings from a study led by a Mayo Clinic rheumatologist indicate that men with knee osteoarthritis who smoke experience greater cartilage loss and more severe pain than men who do not smoke. Results will be published online this week in the Annals of the Rheumatic Diseases.
Knee osteoarthritis is one of the leading causes of disability in elders.
“This is a novel finding,” says Shreyasee Amin, M.D., Mayo Clinic rheumatologist and lead study researcher. “Previous studies showed no association between cigarette smoking and knee osteoarthritis or even a protective effect of smoking.”
The finding that cigarette smoking plays a role in the worsening of knee osteoarthritis is important, says Dr. Amin, as it is a potentially modifiable risk factor.
To conduct this study, the researchers examined 159 men with symptomatic knee osteoarthritis who participated in a prospective study on the natural history of the condition, the Boston Osteoarthritis of the Knee Study. The current study focused on men, as there were too few women in the original group studied who smoked (4 percent). The researchers took MRIs (magnetic resonance images) of the more symptomatic knee of each patient at the study beginning, and also 15 and 30 months later. Cartilage loss over follow-up, based on knee MRIs, was determined at the tibiofemoral joint (the connection between the thighbone and shinbone) and the patellofemoral joint (the junction of the knee cap and the thigh bone) in the knees, and a scoring tool was used to assess knee pain severity. Nineteen, or 12 percent, of the men were current smokers at the study’s start. These men also were leaner and younger than other study participants, so the researchers adjusted for these factors. The investigators found current smokers had a 2.3 fold increased risk of cartilage loss at the medial tibiofemoral joint and a 2.5 fold increased risk of cartilage loss at the patellofemoral joint compared to the men who had quit smoking or never smoked. Current smokers also had higher pain scores than men who were not current smokers, at the beginning of the study (60.5 vs. 45.0, with 100 as the highest possible pain score) and at follow up (59.4 vs. 44.3).
The association between smoking and cartilage loss in knee osteoarthritis could be explained by one or more of the following theories, according to the researchers:
Smoking may disorder the cells and inhibit cell proliferation in the knee cartilage
Smoking may increase oxidant stress, which contributes to cartilage loss
Smoking may raise carbon monoxide levels in arterial blood, contributing to tissue hypoxia (insufficient blood oxygenation), which could impair cartilage repair
Dr. Amin and colleagues believe that the increased pain experienced by smokers with knee osteoarthritis may not be due to the effect of smoking on cartilage loss, as cartilage does not have pain fibers. They have several theories for the link:
Smoking may affect other knee joint structures mediating knee pain
Smoking may affect one’s pain threshold for knee or other musculoskeletal pain
Dr. Amin says these findings are provocative and deserve further study, especially given the number of potential ways in which cigarette smoking could have a negative effect on knee joint cartilage.
Osteoarthritis, sometimes called degenerative joint disease or osteoarthrosis, is the most common form of arthritis. Osteoarthritis is characterized by the breakdown of joint cartilage and may affect any bodily joint, including those in the fingers, hips, knees, lower back and feet, though weight-bearing joints such as the knees are most susceptible. As cartilage slowly deteriorates over the years, chronic pain or varying amounts of discomfort can arise when standing and walking, and swelling also may occur with knee osteoarthritis. Over time, the cartilage deteriorates, and its smooth surface roughens. Eventually, if the cartilage wears down completely, bone may rub on bone, causing the ends of the bones to become damaged and the joints to become more painful. There is no known cause or cure for osteoarthritis, but available treatments can relieve pain and help patients remain active.
Knee osteoarthritis is one of the leading causes of disability in elders.
“This is a novel finding,” says Shreyasee Amin, M.D., Mayo Clinic rheumatologist and lead study researcher. “Previous studies showed no association between cigarette smoking and knee osteoarthritis or even a protective effect of smoking.”
The finding that cigarette smoking plays a role in the worsening of knee osteoarthritis is important, says Dr. Amin, as it is a potentially modifiable risk factor.
To conduct this study, the researchers examined 159 men with symptomatic knee osteoarthritis who participated in a prospective study on the natural history of the condition, the Boston Osteoarthritis of the Knee Study. The current study focused on men, as there were too few women in the original group studied who smoked (4 percent). The researchers took MRIs (magnetic resonance images) of the more symptomatic knee of each patient at the study beginning, and also 15 and 30 months later. Cartilage loss over follow-up, based on knee MRIs, was determined at the tibiofemoral joint (the connection between the thighbone and shinbone) and the patellofemoral joint (the junction of the knee cap and the thigh bone) in the knees, and a scoring tool was used to assess knee pain severity. Nineteen, or 12 percent, of the men were current smokers at the study’s start. These men also were leaner and younger than other study participants, so the researchers adjusted for these factors. The investigators found current smokers had a 2.3 fold increased risk of cartilage loss at the medial tibiofemoral joint and a 2.5 fold increased risk of cartilage loss at the patellofemoral joint compared to the men who had quit smoking or never smoked. Current smokers also had higher pain scores than men who were not current smokers, at the beginning of the study (60.5 vs. 45.0, with 100 as the highest possible pain score) and at follow up (59.4 vs. 44.3).
The association between smoking and cartilage loss in knee osteoarthritis could be explained by one or more of the following theories, according to the researchers:
Smoking may disorder the cells and inhibit cell proliferation in the knee cartilage
Smoking may increase oxidant stress, which contributes to cartilage loss
Smoking may raise carbon monoxide levels in arterial blood, contributing to tissue hypoxia (insufficient blood oxygenation), which could impair cartilage repair
Dr. Amin and colleagues believe that the increased pain experienced by smokers with knee osteoarthritis may not be due to the effect of smoking on cartilage loss, as cartilage does not have pain fibers. They have several theories for the link:
Smoking may affect other knee joint structures mediating knee pain
Smoking may affect one’s pain threshold for knee or other musculoskeletal pain
Dr. Amin says these findings are provocative and deserve further study, especially given the number of potential ways in which cigarette smoking could have a negative effect on knee joint cartilage.
Osteoarthritis, sometimes called degenerative joint disease or osteoarthrosis, is the most common form of arthritis. Osteoarthritis is characterized by the breakdown of joint cartilage and may affect any bodily joint, including those in the fingers, hips, knees, lower back and feet, though weight-bearing joints such as the knees are most susceptible. As cartilage slowly deteriorates over the years, chronic pain or varying amounts of discomfort can arise when standing and walking, and swelling also may occur with knee osteoarthritis. Over time, the cartilage deteriorates, and its smooth surface roughens. Eventually, if the cartilage wears down completely, bone may rub on bone, causing the ends of the bones to become damaged and the joints to become more painful. There is no known cause or cure for osteoarthritis, but available treatments can relieve pain and help patients remain active.
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