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- 39 percent reduced risk seen in a meta-analysis.
- Selenium effects may vary according to individual's characteristics.
A common mineral may provide protection against bladder cancer.
According to results of a study published in the September issue of Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research, selenium intake is associated with decreased risk of bladder cancer.
"The lower the levels of selenium, the higher the risk of developing bladder cancer," said lead researcher Núria Malats, M.D., Ph.D., leader of the Genetic and Molecular Epidemiology Group, Human Cancer Genetics Program, Spanish National Cancer Research Center.
Selenium is an essential micronutrient that is incorporated into about 25 proteins, called selenoproteins. Most of these selenoproteins are enzymes with antioxidant properties that prevent cellular damage caused by the by-products of oxygen metabolism, according to Malats.
The main dietary sources of this micronutrient are plant foods grown in selenium-rich soils, animals who graze on these soils and selenium-enriched products.
Using data from seven previously published studies, Malats and colleagues conducted a meta-analysis to evaluate selenium levels measured in serum and toenails and the risk of developing bladder cancer. The data included individuals mostly from the United States, but also from Belgium, Finland and the Netherlands.
The researchers noted a significant protective effect of selenium, mainly among women, which they believe may result from gender-specific differences in the mineral's accumulation and excretion in women.
"Although our results suggest a beneficial effect of high selenium intake for bladder cancer risk, more studies are needed to confirm these findings before an enforcement of high selenium intake is recommended," Malats said.
Cancer Epidemiology, Biomarkers & Prevention Editorial Board Member Elizabeth A. Platz, Sc.D., M.P.H., said, "these findings provide a valuable lead for what to do next to understand if there is a role for selenium supplementation in bladder cancer prevention."
Tuesday, August 31, 2010
Combining resistance and endurance training best for heart health
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A study of triathletes published in the online edition and October issue of Radiology reveals that the heart adapts to triathlon training by working more efficiently.
"To our knowledge, this is the first study using MRI to investigate effects of triathlon training on cardiac adaptations," said lead researcher Michael M. Lell, M.D., associate professor at the University of Erlangen-Nuremberg in Erlangen, Germany.
Dr. Lell and colleagues conducted cardiac MRI on 26 professional male triathletes (mean age 27.9) and 27 male controls (mean age 27.3), who were recreationally active no more than three hours per week. Triathletes in the study were top national and international competitors with six or more years of continuous training. Triathlons are multi-sport events consisting of swimming, cycling and running various distances in succession.
The cardiac MR images revealed that, compared to the recreational athletes, the triathletes had larger left atria and larger right and left ventricles. The triathletes' left and right ventricles also had greater muscle mass and wall thickness.
"In competitive athletes, it is important to distinguish physiological adaptations as a result of training from pathological conditions such as cardiomyopathy, the most common cause of sudden cardiac death," Dr. Lell said.
In cardiomyopathy, the size of the heart's four chambers and the thickness of the heart wall become asymmetrical, and the heart muscle is unable to pump effectively.
"The cardiac adaptations in the elite triathletes we studied were characterized by a balanced increase in left and right ventricular muscle mass, wall thickness, dilation and diastolic function," Dr. Lell said. "These adaptations reflect the nature of triathlon training, which has both endurance and resistance components."
Dynamic or endurance training includes activities such as running and swimming. Weightlifting is an example of static or resistance training, and cycling is a combination of both forms of exercise. Excessive training in either resistance or endurance disciplines leads to specific heart adaptations, and extreme endurance training is thought to be associated with a predisposition to sudden cardiac events.
"Cardiac adaptations in elite triathletes in our study were not associated with sudden cardiac death," Dr. Lell said.
The triathletes' resting heart rates were also 17 percent lower than those of the control group, which leads to greater cardiac blood supply and more economized heart function.
"The hearts of the triathletes in our study are stronger and able to manage the same workload with less effort," said Dr. Lell.
A study of triathletes published in the online edition and October issue of Radiology reveals that the heart adapts to triathlon training by working more efficiently.
"To our knowledge, this is the first study using MRI to investigate effects of triathlon training on cardiac adaptations," said lead researcher Michael M. Lell, M.D., associate professor at the University of Erlangen-Nuremberg in Erlangen, Germany.
Dr. Lell and colleagues conducted cardiac MRI on 26 professional male triathletes (mean age 27.9) and 27 male controls (mean age 27.3), who were recreationally active no more than three hours per week. Triathletes in the study were top national and international competitors with six or more years of continuous training. Triathlons are multi-sport events consisting of swimming, cycling and running various distances in succession.
The cardiac MR images revealed that, compared to the recreational athletes, the triathletes had larger left atria and larger right and left ventricles. The triathletes' left and right ventricles also had greater muscle mass and wall thickness.
"In competitive athletes, it is important to distinguish physiological adaptations as a result of training from pathological conditions such as cardiomyopathy, the most common cause of sudden cardiac death," Dr. Lell said.
In cardiomyopathy, the size of the heart's four chambers and the thickness of the heart wall become asymmetrical, and the heart muscle is unable to pump effectively.
"The cardiac adaptations in the elite triathletes we studied were characterized by a balanced increase in left and right ventricular muscle mass, wall thickness, dilation and diastolic function," Dr. Lell said. "These adaptations reflect the nature of triathlon training, which has both endurance and resistance components."
Dynamic or endurance training includes activities such as running and swimming. Weightlifting is an example of static or resistance training, and cycling is a combination of both forms of exercise. Excessive training in either resistance or endurance disciplines leads to specific heart adaptations, and extreme endurance training is thought to be associated with a predisposition to sudden cardiac events.
"Cardiac adaptations in elite triathletes in our study were not associated with sudden cardiac death," Dr. Lell said.
The triathletes' resting heart rates were also 17 percent lower than those of the control group, which leads to greater cardiac blood supply and more economized heart function.
"The hearts of the triathletes in our study are stronger and able to manage the same workload with less effort," said Dr. Lell.
Diverse diet of veggies may decrease lung cancer risk
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Adding a variety of vegetables to one's diet may help decrease the chance of getting lung cancer, and adding a variety of fruits and vegetables may decrease the risk of squamous cell lung cancer, especially among smokers.
Study results are published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
"Although quitting smoking is the most important preventive action in reducing lung cancer risk, consuming a mix of different types of fruit and vegetables may also reduce risk, independent of the amount, especially among smokers," said H. Bas Bueno-de-Mesquita, M.D., M.P.H., Ph.D., senior scientist and project director of cancer epidemiology at The National Institute for Public Health and the Environment, The Netherlands.
Using information from the ongoing, multi-centered European Prospective Investigation into Cancer and Nutrition (EPIC) study, Bueno-de-Mesquita and colleagues evaluated 452,187 participants with complete information, 1,613 of whom were diagnosed with lung cancer.
Information was obtained on 14 commonly eaten fruits and 26 commonly eaten vegetables. The fruits and vegetables evaluated in the EPIC study consisted of a wide variety of fresh, canned or dried products.
Previous results from the EPIC study showed that the quantity of vegetables and fruits may decrease risk of lung cancer; in particular the risk of one specific type of lung cancer, squamous cell carcinoma, decreased in current smokers.
Regardless of the amount, the researchers on the current study found that risk of lung cancer also decreased when a variety of vegetables were consumed. In addition, the risk of squamous cell carcinoma decreased substantially when a variety of fruits and vegetables were eaten. However, Bueno-de-Mesquita said that they "cannot exclude that these results can still be explained by smoking."
"Fruits and vegetables contain many different bioactive compounds, and it makes sense to assume that it is important that you not only eat the recommended amounts, but also consume a rich mix of these bioactive compounds by consuming a large variety," he said.
While previous research has shown the influence of the quantity of fruits and vegetables on cancer development, Stephen Hecht, Ph.D., editorial board member for Cancer Epidemiology, Biomarkers & Prevention, believes this study is one of the first to evaluate diversity of fruit and vegetable consumption, rather than quantity.
"The results are very interesting and demonstrate a protective effect in smokers. There are still over a billion smokers in the world, and many are addicted to nicotine and cannot stop in spite of their best efforts," added Hecht, who is the Wallin Land Grant Professor of Cancer Prevention at the Masonic Cancer Center, University of Minnesota.
Tobacco smoke contains a complex mixture of cancer causing agents. Therefore, a mixture of protective agents is needed to have any beneficial effect in reducing one's chance of lung cancer, Hecht said.
"Nevertheless, the public should be made aware and be reminded that the only proven way to reduce your risk for lung cancer is to avoid tobacco in all its forms," he said.
Adding a variety of vegetables to one's diet may help decrease the chance of getting lung cancer, and adding a variety of fruits and vegetables may decrease the risk of squamous cell lung cancer, especially among smokers.
Study results are published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
"Although quitting smoking is the most important preventive action in reducing lung cancer risk, consuming a mix of different types of fruit and vegetables may also reduce risk, independent of the amount, especially among smokers," said H. Bas Bueno-de-Mesquita, M.D., M.P.H., Ph.D., senior scientist and project director of cancer epidemiology at The National Institute for Public Health and the Environment, The Netherlands.
Using information from the ongoing, multi-centered European Prospective Investigation into Cancer and Nutrition (EPIC) study, Bueno-de-Mesquita and colleagues evaluated 452,187 participants with complete information, 1,613 of whom were diagnosed with lung cancer.
Information was obtained on 14 commonly eaten fruits and 26 commonly eaten vegetables. The fruits and vegetables evaluated in the EPIC study consisted of a wide variety of fresh, canned or dried products.
Previous results from the EPIC study showed that the quantity of vegetables and fruits may decrease risk of lung cancer; in particular the risk of one specific type of lung cancer, squamous cell carcinoma, decreased in current smokers.
Regardless of the amount, the researchers on the current study found that risk of lung cancer also decreased when a variety of vegetables were consumed. In addition, the risk of squamous cell carcinoma decreased substantially when a variety of fruits and vegetables were eaten. However, Bueno-de-Mesquita said that they "cannot exclude that these results can still be explained by smoking."
"Fruits and vegetables contain many different bioactive compounds, and it makes sense to assume that it is important that you not only eat the recommended amounts, but also consume a rich mix of these bioactive compounds by consuming a large variety," he said.
While previous research has shown the influence of the quantity of fruits and vegetables on cancer development, Stephen Hecht, Ph.D., editorial board member for Cancer Epidemiology, Biomarkers & Prevention, believes this study is one of the first to evaluate diversity of fruit and vegetable consumption, rather than quantity.
"The results are very interesting and demonstrate a protective effect in smokers. There are still over a billion smokers in the world, and many are addicted to nicotine and cannot stop in spite of their best efforts," added Hecht, who is the Wallin Land Grant Professor of Cancer Prevention at the Masonic Cancer Center, University of Minnesota.
Tobacco smoke contains a complex mixture of cancer causing agents. Therefore, a mixture of protective agents is needed to have any beneficial effect in reducing one's chance of lung cancer, Hecht said.
"Nevertheless, the public should be made aware and be reminded that the only proven way to reduce your risk for lung cancer is to avoid tobacco in all its forms," he said.
Monday, August 30, 2010
Jon's Health Tips - Latest Health Research
Lots of new research in the last 3 weeks, almost all of which confirms or reinforces my own practices.
1. I already take L-arginine amino acid – I will be taking more of it starting today:
L-arginine amino acid produces a 'striking' endurance boost:
2. Playing soccer 3 times a week, and kayaking 2-3 times a week will keep be alive and bright:
Light and moderate physical activity reduces the risk of early death
And
Even walking can enhance the connectivity of important brain circuits, combat declines in brain function associated with aging and increase performance on cognitive tasks.
3. I’ll continue to drink to this:
Findings confirm an association between moderate drinking and reduced mortality among older adults.
And
Moderate drinking, especially wine, associated with better cognitive function
But
Alcohol intake increases certain types of (relatively rare) breast cancer, but not of the most common breast cancer
And
Women who drink beer more likely to develop psoriasis
4. I’m going to try to drink less bottled green tea and more brewed green tea,
Bottled tea beverages may contain fewer polyphenols than brewed tea
5. But I drink bottled tea before soccer games mainly for the caffeine:
Caffeine Only Benefit Of Energy Drinks
6. I have to keep up
My berry consumption:
Eating berries may activate the brain's natural housekeeper for healthy aging
My Mediterranean diet:
Mediterranean diet = skin cancer prevention
Avoiding red and processed meats
Healthier protein-rich foods instead of red and processed meats may reduce heart disease risk
My 85% cocoa dark chocolate consumption:
Moderate chocolate consumption linked to lower risks of heart failure
My green leafy vegetables:
Green leafy vegetables reduce diabetes risk
And my green tea
Green Tea Extract Appears to Keep Cancer in Check
7. A reader alerted me to this research
Increased Risk of Stroke Associated With Nonsteroidal Anti-Inflammatory Drugs
And more bad news about one NSAID:
Acetaminophen use in adolescents linked to doubled risk of asthma
But I did some further research about the one NSAID I use regularly:
Aspirin lowers stroke risk.
8. So it’s good that I take aspirin, etc. because I’m at greater risk than some – you want to argue with me about that:
Antagonistic people may increase heart attack, stroke risk
9. I'm very happy with my statin regime:
Free statins with fast food could neutralize heart risk, scientists say
10. I will continue to take zinc:
Adequate zinc eases pneumonia in elderly
11. I stopped drinking cranberry juice and taking cranberry pills earlier this summer. Guess what I’m suffering right now:
Cranberry Juice Fights Bacteria That Cause Urinary Tract Infections
12. I may have to resume taking folate supplements, although my diet is pretty good on that, but I'm not bummed about it:
Lower levels of folate=symptoms of dementia and poor brain function, also called "cognitive decline"
Not what I usually cover, but important:
RECOGNIZING A STROKE
1. I already take L-arginine amino acid – I will be taking more of it starting today:
L-arginine amino acid produces a 'striking' endurance boost:
Research from the University of Exeter has revealed taking a dietary supplement to boost nitric oxide in the body can significantly boost stamina during high-intensity exercise.
The study has important implications for athletes, as results suggest that taking the supplement can allow people to exercise up to 20% longer .
The report, published on-line by the Journal of Applied Physiology, found taking the supplement:
- Improves severe-intensity exercise endurance by 20%
- Significantly reduces systolic blood pressure
- Reduces the oxygen cost of exercise
2. Playing soccer 3 times a week, and kayaking 2-3 times a week will keep be alive and bright:
Light and moderate physical activity reduces the risk of early death
And
Even walking can enhance the connectivity of important brain circuits, combat declines in brain function associated with aging and increase performance on cognitive tasks.
3. I’ll continue to drink to this:
Findings confirm an association between moderate drinking and reduced mortality among older adults.
And
Moderate drinking, especially wine, associated with better cognitive function
But
Alcohol intake increases certain types of (relatively rare) breast cancer, but not of the most common breast cancer
We found that women who drank one or more drinks per day had about double the risk of lobular type breast cancer, but no increase in their risk of ductal type breast cancer. It is important to note that ductal cancer is much more common than lobular cancer accounting for about 70 percent of all breast cancers whereas lobular cancer accounts for only about 10-15 percent of cases.
And
Women who drink beer more likely to develop psoriasis
Regular beer—but not light beer or other types of alcohol—appears to be associated with an increased risk of developing psoriasis.
Women who drank five or more beers per week had a risk for the condition that was 1.8 times higher. Light beer, red wine, white wine and liquor were not associated with psoriasis risk.
4. I’m going to try to drink less bottled green tea and more brewed green tea,
Bottled tea beverages may contain fewer polyphenols than brewed tea
Measurements of healthful antioxidant levels in commercial bottled tea beverages has concluded that health-conscious consumers may not be getting what they pay for: healthful doses of those antioxidants, or "poylphenols," that may ward off a range of diseases. Analysis of tea beverages found that the polyphenol content is extremely low."
5. But I drink bottled tea before soccer games mainly for the caffeine:
Caffeine Only Benefit Of Energy Drinks
"Most of the performance-enhancing effects of energy drinks can be linked to their caffeine content," she says. "Caffeine has been consistently been observed to enhance aerobic performance, although its effects on anaerobic performance may vary."
6. I have to keep up
My berry consumption:
Eating berries may activate the brain's natural housekeeper for healthy aging
My Mediterranean diet:
Mediterranean diet = skin cancer prevention
Avoiding red and processed meats
Healthier protein-rich foods instead of red and processed meats may reduce heart disease risk
The data also showed that eating more servings of poultry, fish and nuts was significantly associated with a decreased risk of coronary heart disease. Compared to one serving each day of red meat, women who substituted other protein-rich foods experienced significantly lower risk of coronary heart disease:
30 percent lower risk with one serving each day of nuts
24 percent lower risk with one serving each day of fish
19 percent lower risk with one serving each day of poultry
13 percent lower risk with one serving each day of low-fat dairy products
My 85% cocoa dark chocolate consumption:
Moderate chocolate consumption linked to lower risks of heart failure
Women who ate an average of one to two servings of the high-quality chocolate per week had a 32 percent lower risk of developing heart failure.
Those who had one to three servings per month had a 26 percent lower risk.
My green leafy vegetables:
Green leafy vegetables reduce diabetes risk
And my green tea
Green Tea Extract Appears to Keep Cancer in Check
7. A reader alerted me to this research
Increased Risk of Stroke Associated With Nonsteroidal Anti-Inflammatory Drugs
And more bad news about one NSAID:
Acetaminophen use in adolescents linked to doubled risk of asthma
But I did some further research about the one NSAID I use regularly:
Aspirin lowers stroke risk.
8. So it’s good that I take aspirin, etc. because I’m at greater risk than some – you want to argue with me about that:
Antagonistic people may increase heart attack, stroke risk
Antagonistic people, particularly those who are competitive and aggressive, may be increasing their risk of heart attack or stroke.
9. I'm very happy with my statin regime:
Free statins with fast food could neutralize heart risk, scientists say
Fast food outlets could provide statin drugs free of charge so that customers can neutralize the heart disease dangers of fatty food, researchers at Imperial College London suggest in a new study published this week
Fast food outlets could provide statin drugs free of charge so that customers can neutralise the heart disease dangers of fatty food, researchers at Imperial College London suggest in a new study published this week.
Statins reduce the amount of unhealthy "LDL" cholesterol in the blood. A wealth of trial data has proven them to be highly effective at lowering a person's heart attack risk.
One statin, simvastatin, is already available in Great Britain in low doses (10mg) over the counter at pharmacies without a prescription
Statins have among the best safety profiles of any medication. A very small proportion of regular statin users experience significant side effects, with problems in the liver and kidneys reported in between 1 in 1,000 and 1 in 10,000 people.
10. I will continue to take zinc:
Adequate zinc eases pneumonia in elderly
11. I stopped drinking cranberry juice and taking cranberry pills earlier this summer. Guess what I’m suffering right now:
Cranberry Juice Fights Bacteria That Cause Urinary Tract Infections
12. I may have to resume taking folate supplements, although my diet is pretty good on that, but I'm not bummed about it:
Lower levels of folate=symptoms of dementia and poor brain function, also called "cognitive decline"
An analysis of volunteers' blood samples showed that lower levels of one B vitamin, folate, were associated with symptoms of dementia and poor brain function, also called "cognitive decline," as determined by standard tests of memory and other factors. The impairments were detectable even though less than 1 percent of the volunteers were actually deficient in folate.
In women, but not men, low levels of folate were associated with symptoms of depression.
Not what I usually cover, but important:
RECOGNIZING A STROKE
Sometimes symptoms of a stroke are difficult to identify. Unfortunately, the lack of awareness spells disaster. The stroke victim may suffer death or severe brain damage when people nearby fail to recognize the symptoms of a stroke.
Now doctors say a bystander can recognize a stroke by asking three simple questions:
S *Ask the individual to SMILE.
T *Ask the person to TALK and SPEAK A SIMPLE SENTENCE (Coherently)
(i.e. It is sunny out today.)
R *Ask him or her to RAISE BOTH ARMS.
If he or she has trouble with ANY ONE of these tasks, call emergency number immediately and describe the symptoms to the dispatcher.
New sign of a stroke - Stick Out Your Tongue.
Another 'sign' of a stroke is this: Ask the person to 'stick' out his tongue. If the tongue is 'crooked', if it goes to one side or the other, that is also an indication of a stroke.
A neurologist says that if he can get to a stroke victim within 3 hours, he can totally reverse the effects of a stroke...totally. He said the trick was getting a stroke recognized, diagnosed and then getting the patient medically cared for within 3 hours, which is tough..
Risk of Stroke from Aspirin
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The American Heart Association:
Another study:
The Mayo Clinic agrees:
The American Heart Association:
Background— Low-dose aspirin is an important therapeutic option in the secondary prevention of myocardial infarction (MI) and ischemic stroke, especially in light of its unique cost-effectiveness and widespread availability. In addition, based on the results of a number of large studies, aspirin is also widely used in the primary prevention of MI. This review provides an update of the available data to offer greater clarity regarding the risks of aspirin with respect to hemorrhagic stroke, as well as insights regarding patient selection to minimize the risk of this complication.
Summary of Review— In the secondary prevention of cardiovascular, cerebrovascular, and ischemic events, the evidence supports that the benefits of aspirin treatment significantly outweigh the risk of a major hemorrhage. The evidence from primary prevention of MI studies, including that from the recent Women’s Health Study evaluation of aspirin use in healthy women, demonstrate that the increased risk for hemorrhagic stroke is small, is comparable to the secondary prevention studies, and fails to achieve statistical significance. A reasonable estimate of the risk of hemorrhagic stroke associated with the use of aspirin in primary prevention patients is 0.2 events per 1000 patient-years, which is comparable to estimates of the risk associated with the use of aspirin in secondary prevention patients.
Conclusions— When considering whether aspirin is appropriate, the absolute therapeutic cardiovascular benefits of aspirin must be balanced with the possible risks associated with its use, with the most serious being hemorrhagic stroke.
Another study:
This study revealed that the 100 mg dose of aspirin every other day caused a 24 percent drop in the risk of ischemic stroke, which is the more common kind of stroke, and an insignificant increase in the risk of hemorrhagic stroke, hence the overall reduction in stroke risk of 17 percent.
The Mayo Clinic agrees:
For men of all ages, aspirin can:
Prevent a first and second heart attack
Reduce heart disease risk
For women younger than 65, aspirin can:
Prevent a first stroke
Prevent a second heart attack
Reduce heart disease risk
For women 65 and older, aspirin can:
Prevent a first and second heart attack
Prevent a first stroke
Reduce heart disease risk
Friday, August 27, 2010
L-arginine amino acid produces a 'striking' endurance boost
Ω
Research from the University of Exeter has revealed taking a dietary supplement to boost nitric oxide in the body can significantly boost stamina during high-intensity exercise.
The study has important implications for athletes, as results suggest that taking the supplement can allow people to exercise up to 20% longer and could produce a 1-2% improvement in race times.
This comes on the back of previous research from Exeter which showed that the high nitrate content of beetroot juice, which also boosts nitric oxide in the body, has a similar effect on performance.
However, the latest study gets the nitric oxide into the body through a different biological process – and now the researchers are hoping to find out whether combining the two methods could bring an even greater improvement in athletic performance.
Professor Andrew Jones, from the University's School of Sport and Health Sciences, said: "The research found that when the dietary supplement was used there was a striking increase in performance by altering the use of oxygen during exercise.
"This is important for endurance athletes as we would expect the supplement to bring a 1-2% improvement in race times. While this may seem small, this is a very meaningful improvement – particularly at elite levels where small gains can be the difference between winning and losing."
For the research, nine healthy males were put through several different physical challenges on a cycling ergometer to measure their performance under different levels of exercise intensity.
Participants were randomly assigned to take either a blackcurrant cordial placebo drink or the genuine supplement, which was Ark 1 from Arkworld International Limited – which contains the L-arginine amino acid which enhances the production of nitric oxide in the body.
The report, published on-line by the Journal of Applied Physiology, found taking the supplement:
- Improves severe-intensity exercise endurance by 20%
- Significantly reduces systolic blood pressure
- Reduces the oxygen cost of exercise
Research from the University of Exeter has revealed taking a dietary supplement to boost nitric oxide in the body can significantly boost stamina during high-intensity exercise.
The study has important implications for athletes, as results suggest that taking the supplement can allow people to exercise up to 20% longer and could produce a 1-2% improvement in race times.
This comes on the back of previous research from Exeter which showed that the high nitrate content of beetroot juice, which also boosts nitric oxide in the body, has a similar effect on performance.
However, the latest study gets the nitric oxide into the body through a different biological process – and now the researchers are hoping to find out whether combining the two methods could bring an even greater improvement in athletic performance.
Professor Andrew Jones, from the University's School of Sport and Health Sciences, said: "The research found that when the dietary supplement was used there was a striking increase in performance by altering the use of oxygen during exercise.
"This is important for endurance athletes as we would expect the supplement to bring a 1-2% improvement in race times. While this may seem small, this is a very meaningful improvement – particularly at elite levels where small gains can be the difference between winning and losing."
For the research, nine healthy males were put through several different physical challenges on a cycling ergometer to measure their performance under different levels of exercise intensity.
Participants were randomly assigned to take either a blackcurrant cordial placebo drink or the genuine supplement, which was Ark 1 from Arkworld International Limited – which contains the L-arginine amino acid which enhances the production of nitric oxide in the body.
The report, published on-line by the Journal of Applied Physiology, found taking the supplement:
- Improves severe-intensity exercise endurance by 20%
- Significantly reduces systolic blood pressure
- Reduces the oxygen cost of exercise
Walking can enhance the connectivity of important brain circuits, combat declines in brain function associated with aging and increase performance on
Ω
A group of “professional couch potatoes,” as one researcher described them, has proven that even moderate exercise – in this case walking at one’s own pace for 40 minutes three times a week – can enhance the connectivity of important brain circuits, combat declines in brain function associated with aging and increase performance on cognitive tasks.
Moderate walking three times per week for a year increased brain connectivity and brain function in older adults, the researchers found. | Photo by Elise McAuley for the Exercise Psychology Laboratory at the U. of I.
The study, in Frontiers in Aging Neuroscience, followed 65 adults, aged 59 to 80, who joined a walking group or stretching and toning group for a year. All of the participants were sedentary before the study, reporting less than two episodes of physical activity lasting 30 minutes or more in the previous six months. The researchers also measured brain activity in 32 younger (18- to 35-year-old) adults.
Rather than focusing on specific brain structures, the study looked at activity in brain regions that function together as networks.
“Almost nothing in the brain gets done by one area – it’s more of a circuit,” said University of Illinois psychology professor and Beckman Institute Director Art Kramer, who led the study with kinesiology and community health professor Edward McAuley and doctoral student Michelle Voss. “These networks can become more or less connected. In general, as we get older, they become less connected, so we were interested in the effects of fitness on connectivity of brain networks that show the most dysfunction with age.”
Neuroscientists have identified several distinct brain circuits. Perhaps the most intriguing is the default mode network (DMN), which dominates brain activity when a person is least engaged with the outside world – either passively observing something or simply daydreaming.
Previous studies found that a loss of coordination in the DMN is a common symptom of aging and in extreme cases can be a marker of disease, Voss said.
“For example, people with Alzheimer’s disease tend to have less activity in the default mode network and they tend to have less connectivity,” she said. Low connectivity means that the different parts of the circuit are not operating in sync. Like poorly trained athletes on a rowing team, the brain regions that make up the circuit lack coordination and so do not function at optimal efficiency or speed, Voss said.
In a healthy young brain, activity in the DMN quickly diminishes when a person engages in an activity that requires focus on the external environment. Older people, people with Alzheimer’s disease and those who are schizophrenic have more difficulty “down-regulating” the DMN so that other brain networks can come to the fore, Kramer said.
A recent study by Kramer, Voss and their colleagues found that older adults who are more fit tend to have better connectivity in specific regions of the DMN than their sedentary peers. Those with more connectivity in the DMN also tend to be better at planning, prioritizing, strategizing and multi-tasking.
The new study used functional magnetic resonance imaging (fMRI) to determine whether aerobic activity increased connectivity in the DMN or other brain networks. The researchers measured participants’ brain connectivity and performance on cognitive tasks at the beginning of the study, at six months and after a year of either walking or toning and stretching.
At the end of the year, DMN connectivity was significantly improved in the brains of the older walkers, but not in the stretching and toning group, the researchers report.
The walkers also had increased connectivity in parts of another brain circuit (the fronto-executive network, which aids in the performance of complex tasks) and they did significantly better on cognitive tests than their toning and stretching peers.
Previous studies have found that aerobic exercise can enhance the function of specific brain structures, Kramer said. This study shows that even moderate aerobic exercise also improves the coordination of important brain networks.
“The higher the connectivity, the better the performance on some of these cognitive tasks, especially the ones we call executive control tasks – things like planning, scheduling, dealing with ambiguity, working memory and multitasking,” Kramer said. These are the very skills that tend to decline with aging, he said.
A group of “professional couch potatoes,” as one researcher described them, has proven that even moderate exercise – in this case walking at one’s own pace for 40 minutes three times a week – can enhance the connectivity of important brain circuits, combat declines in brain function associated with aging and increase performance on cognitive tasks.
Moderate walking three times per week for a year increased brain connectivity and brain function in older adults, the researchers found. | Photo by Elise McAuley for the Exercise Psychology Laboratory at the U. of I.
The study, in Frontiers in Aging Neuroscience, followed 65 adults, aged 59 to 80, who joined a walking group or stretching and toning group for a year. All of the participants were sedentary before the study, reporting less than two episodes of physical activity lasting 30 minutes or more in the previous six months. The researchers also measured brain activity in 32 younger (18- to 35-year-old) adults.
Rather than focusing on specific brain structures, the study looked at activity in brain regions that function together as networks.
“Almost nothing in the brain gets done by one area – it’s more of a circuit,” said University of Illinois psychology professor and Beckman Institute Director Art Kramer, who led the study with kinesiology and community health professor Edward McAuley and doctoral student Michelle Voss. “These networks can become more or less connected. In general, as we get older, they become less connected, so we were interested in the effects of fitness on connectivity of brain networks that show the most dysfunction with age.”
Neuroscientists have identified several distinct brain circuits. Perhaps the most intriguing is the default mode network (DMN), which dominates brain activity when a person is least engaged with the outside world – either passively observing something or simply daydreaming.
Previous studies found that a loss of coordination in the DMN is a common symptom of aging and in extreme cases can be a marker of disease, Voss said.
“For example, people with Alzheimer’s disease tend to have less activity in the default mode network and they tend to have less connectivity,” she said. Low connectivity means that the different parts of the circuit are not operating in sync. Like poorly trained athletes on a rowing team, the brain regions that make up the circuit lack coordination and so do not function at optimal efficiency or speed, Voss said.
In a healthy young brain, activity in the DMN quickly diminishes when a person engages in an activity that requires focus on the external environment. Older people, people with Alzheimer’s disease and those who are schizophrenic have more difficulty “down-regulating” the DMN so that other brain networks can come to the fore, Kramer said.
A recent study by Kramer, Voss and their colleagues found that older adults who are more fit tend to have better connectivity in specific regions of the DMN than their sedentary peers. Those with more connectivity in the DMN also tend to be better at planning, prioritizing, strategizing and multi-tasking.
The new study used functional magnetic resonance imaging (fMRI) to determine whether aerobic activity increased connectivity in the DMN or other brain networks. The researchers measured participants’ brain connectivity and performance on cognitive tasks at the beginning of the study, at six months and after a year of either walking or toning and stretching.
At the end of the year, DMN connectivity was significantly improved in the brains of the older walkers, but not in the stretching and toning group, the researchers report.
The walkers also had increased connectivity in parts of another brain circuit (the fronto-executive network, which aids in the performance of complex tasks) and they did significantly better on cognitive tests than their toning and stretching peers.
Previous studies have found that aerobic exercise can enhance the function of specific brain structures, Kramer said. This study shows that even moderate aerobic exercise also improves the coordination of important brain networks.
“The higher the connectivity, the better the performance on some of these cognitive tasks, especially the ones we call executive control tasks – things like planning, scheduling, dealing with ambiguity, working memory and multitasking,” Kramer said. These are the very skills that tend to decline with aging, he said.
Blood Clots/Stroke - They Now Have a Fourth Indicator, the Tongue.
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STROKE IDENTIFICATION:
During a BBQ, a woman stumbled and took a little fall - she assured everyone that she was fine (they offered to call the paramedics). She said she had just tripped over a brick because of her new shoes.
They got her cleaned up and got her a new plate of food. While she appeared a bit shaken up, Jane went about enjoying herself for the rest of the evening.
Jane's husband called later telling everyone that his wife had been taken to the hospital and at 6:00 p.m. Jane passed away. She had suffered a stroke at the BBQ. Had they known how to identify the signs of a stroke, perhaps Jane would be with us today. Some don't die. They end up in a helpless, hopeless condition instead.
It only takes a minute to read this...
A neurologist says that if he can get to a stroke victim within 3 hours, he can totally reverse the effects of a stroke...totally. He said the trick was getting a stroke recognized, diagnosed and then getting the patient medically cared for within 3 hours, which is tough..
RECOGNIZING A STROKE
Thank God for the sense to remember the '3' steps, STR. Read and Learn!
Sometimes symptoms of a stroke are difficult to identify. Unfortunately, the lack of awareness spells disaster. The stroke victim may suffer death or severe brain damage when people nearby fail to recognize the symptoms of a stroke.
Now doctors say a bystander can recognize a stroke by asking three simple questions:
S *Ask the individual to SMILE.
T *Ask the person to TALK and SPEAK A SIMPLE SENTENCE (Coherently)
(i.e. It is sunny out today.)
R *Ask him or her to RAISE BOTH ARMS.
If he or she has trouble with ANY ONE of these tasks, call emergency number immediately and describe the symptoms to the dispatcher.
New sign of a stroke - Stick Out Your Tongue.
Another 'sign' of a stroke is this: Ask the person to 'stick' out his tongue. If the tongue is 'crooked', if it goes to one side or the other, that is also an indication of a stroke.
A cardiologist says if everyone who gets this email sends it to 10 people, you can bet that at least one life will be saved.
I have done my part. Will you?
STROKE IDENTIFICATION:
During a BBQ, a woman stumbled and took a little fall - she assured everyone that she was fine (they offered to call the paramedics). She said she had just tripped over a brick because of her new shoes.
They got her cleaned up and got her a new plate of food. While she appeared a bit shaken up, Jane went about enjoying herself for the rest of the evening.
Jane's husband called later telling everyone that his wife had been taken to the hospital and at 6:00 p.m. Jane passed away. She had suffered a stroke at the BBQ. Had they known how to identify the signs of a stroke, perhaps Jane would be with us today. Some don't die. They end up in a helpless, hopeless condition instead.
It only takes a minute to read this...
A neurologist says that if he can get to a stroke victim within 3 hours, he can totally reverse the effects of a stroke...totally. He said the trick was getting a stroke recognized, diagnosed and then getting the patient medically cared for within 3 hours, which is tough..
RECOGNIZING A STROKE
Thank God for the sense to remember the '3' steps, STR. Read and Learn!
Sometimes symptoms of a stroke are difficult to identify. Unfortunately, the lack of awareness spells disaster. The stroke victim may suffer death or severe brain damage when people nearby fail to recognize the symptoms of a stroke.
Now doctors say a bystander can recognize a stroke by asking three simple questions:
S *Ask the individual to SMILE.
T *Ask the person to TALK and SPEAK A SIMPLE SENTENCE (Coherently)
(i.e. It is sunny out today.)
R *Ask him or her to RAISE BOTH ARMS.
If he or she has trouble with ANY ONE of these tasks, call emergency number immediately and describe the symptoms to the dispatcher.
New sign of a stroke - Stick Out Your Tongue.
Another 'sign' of a stroke is this: Ask the person to 'stick' out his tongue. If the tongue is 'crooked', if it goes to one side or the other, that is also an indication of a stroke.
A cardiologist says if everyone who gets this email sends it to 10 people, you can bet that at least one life will be saved.
I have done my part. Will you?
Wednesday, August 25, 2010
Cranberry Juice Fights Bacteria That Cause Urinary Tract Infections
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Scientists today reported new scientific evidence on the effectiveness of that old folk remedy –– cranberry juice –– for urinary tract infections, at the 240th National Meeting of the American Chemical Society (ACS), being held here this week.
“A number of controlled clinical trials _ these are carefully designed and conducted scientific studies done in humans _ have concluded that cranberry juice really is effective for preventing urinary tract infections,” said Terri Anne Camesano, Ph.D., who led the study. “That has important implications, considering the size of the problem and the health care costs involved.”
Estimates suggest that urinary tract infections (UTIs) account for about 8 million medical visits each year, at a total cost of more than $1.6 billion. UTIs involve bacterial infections of the urinary tract and can occur anywhere between the urethra, the opening where urine is excreted from the body, and the kidney. Women are frequent victims, with at least 1 in 3 experiencing a UTI. Studies suggest that only half of women with UTIs seek medical care for the mildest symptoms, which include burning and urgency._Camesano, who is with the Worcester Polytechnic Institute, said the study set out to shed light on how cranberry juice fights E. coli, the most common cause of UTIs. The study involved growing strains of E. coli in urine collected from healthy volunteers before and after consumption of cranberry juice cocktail. That mixture of cranberry juice, water, and sweeteners is the most popular cranberry beverage. The scientists then tested the E. coli for their ability to stick together and form biofilms. Biofilms are thin, slimy layers that provide an environment for bacteria to thrive.
The scientists concluded that cranberry juice cocktail prevents E. coli from sticking to other bacteria and the surface of a plastic petri dish. E. coli adhere to those cells and work together to form a biofilm. The biofilm enables the bacteria to grow and multiply so that an infection can take root, continue, or become more severe. E. coli that doesn’t stick has a better chance of being flushed out of the urinary track. The results suggest that the beneficial substances in cranberry juice could reach the urinary tract and prevent bacterial adhesion within 8 hours after consumption of cranberry juice.
Camesano expressed reservations about self-treating UTIs and said that individuals who suspect an infection should seek medical advice. UTIs can progress rapidly and, if left untreated with antibiotics, result in severe illness, especially in children, individuals with chronic health problems, and the elderly
Scientists today reported new scientific evidence on the effectiveness of that old folk remedy –– cranberry juice –– for urinary tract infections, at the 240th National Meeting of the American Chemical Society (ACS), being held here this week.
“A number of controlled clinical trials _ these are carefully designed and conducted scientific studies done in humans _ have concluded that cranberry juice really is effective for preventing urinary tract infections,” said Terri Anne Camesano, Ph.D., who led the study. “That has important implications, considering the size of the problem and the health care costs involved.”
Estimates suggest that urinary tract infections (UTIs) account for about 8 million medical visits each year, at a total cost of more than $1.6 billion. UTIs involve bacterial infections of the urinary tract and can occur anywhere between the urethra, the opening where urine is excreted from the body, and the kidney. Women are frequent victims, with at least 1 in 3 experiencing a UTI. Studies suggest that only half of women with UTIs seek medical care for the mildest symptoms, which include burning and urgency._Camesano, who is with the Worcester Polytechnic Institute, said the study set out to shed light on how cranberry juice fights E. coli, the most common cause of UTIs. The study involved growing strains of E. coli in urine collected from healthy volunteers before and after consumption of cranberry juice cocktail. That mixture of cranberry juice, water, and sweeteners is the most popular cranberry beverage. The scientists then tested the E. coli for their ability to stick together and form biofilms. Biofilms are thin, slimy layers that provide an environment for bacteria to thrive.
The scientists concluded that cranberry juice cocktail prevents E. coli from sticking to other bacteria and the surface of a plastic petri dish. E. coli adhere to those cells and work together to form a biofilm. The biofilm enables the bacteria to grow and multiply so that an infection can take root, continue, or become more severe. E. coli that doesn’t stick has a better chance of being flushed out of the urinary track. The results suggest that the beneficial substances in cranberry juice could reach the urinary tract and prevent bacterial adhesion within 8 hours after consumption of cranberry juice.
Camesano expressed reservations about self-treating UTIs and said that individuals who suspect an infection should seek medical advice. UTIs can progress rapidly and, if left untreated with antibiotics, result in severe illness, especially in children, individuals with chronic health problems, and the elderly
More Walking, Cycling Linked to Healthier Weights Worldwide
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Amble, stroll or pedal: it’s all good. A new study provides evidence supporting a seemingly obvious _ but unproven _ link between walking- and cycling-friendly communities and lower levels of obesity.
Researchers found that people are more likely to have healthy weights if they live in places where walking and cycling are more common. The link held up among nations, cities and U.S. states.
The research does not prove that living in couch-potato land directly boosts a resident’s risk of being fat.
Still, the study findings suggest, “It’s really important to promote walking and cycling as safe, convenient and feasible modes of getting around on an everyday basis,” said lead author John Pucher, a professor who studies transportation at Rutgers University.
Pucher and colleagues analyzed statistics about walking and cycling for all purposes from 14 countries, including Sweden, Spain and Great Britain. They also looked at statistics about walking and cycling to work (it had to be the main way people got there) in all 50 states and 47 of the 50 largest U.S. cities.
Switzerland, the Netherlands and Spain had the highest levels of walking and cycling among the countries, with the United States in the bottom three with Australia and Canada. Among American cities, the highest rates of walking and cycling to work were in Boston, Washington D.C., San Francisco, Minneapolis and Seattle.
The researchers tried to find links between the levels of walking and cycling and those of physical activity, obesity and diabetes in the geographic areas. Their findings appear in the October issue of the American Journal of Public Health.
There is a connection between more walking and cycling and lower levels of obesity and diabetes, the researchers found. Not surprisingly, they also linked more walking and cycling to higher overall levels of physical activity.
The study does not calculate the overall percentage difference in levels of obesity and diabetes between places with the highest and lowest levels of walking and cycling. Nevertheless, Pucher said readers could calculate those numbers and find other statistics by examining research data.
In the big picture, the study results suggest that a big part of the gaps between American states and cities concerning health can be explained by differences in levels of walking and cycling, Pucher said.
While the link between more exercise and less obesity might seem obvious, he said there is a need for more scientific evidence to back it up. “As obvious as it is,” he said, “it’s shocking that Americans don’t want to do anything about it. It’s amazing how unconcerned most Americans are about this.”
Lawrence Frank, an associate professor who studies transportation at the University of British Columbia, said the study findings reflect the results of previous research that shows the effects of exercise (or the lack of it) on health.
“Physical activity is crucial,” Frank said. “If we keep designing communities in ways that make driving the more rational choice, we can expect health care costs to go up and quality of life to go down.”
Amble, stroll or pedal: it’s all good. A new study provides evidence supporting a seemingly obvious _ but unproven _ link between walking- and cycling-friendly communities and lower levels of obesity.
Researchers found that people are more likely to have healthy weights if they live in places where walking and cycling are more common. The link held up among nations, cities and U.S. states.
The research does not prove that living in couch-potato land directly boosts a resident’s risk of being fat.
Still, the study findings suggest, “It’s really important to promote walking and cycling as safe, convenient and feasible modes of getting around on an everyday basis,” said lead author John Pucher, a professor who studies transportation at Rutgers University.
Pucher and colleagues analyzed statistics about walking and cycling for all purposes from 14 countries, including Sweden, Spain and Great Britain. They also looked at statistics about walking and cycling to work (it had to be the main way people got there) in all 50 states and 47 of the 50 largest U.S. cities.
Switzerland, the Netherlands and Spain had the highest levels of walking and cycling among the countries, with the United States in the bottom three with Australia and Canada. Among American cities, the highest rates of walking and cycling to work were in Boston, Washington D.C., San Francisco, Minneapolis and Seattle.
The researchers tried to find links between the levels of walking and cycling and those of physical activity, obesity and diabetes in the geographic areas. Their findings appear in the October issue of the American Journal of Public Health.
There is a connection between more walking and cycling and lower levels of obesity and diabetes, the researchers found. Not surprisingly, they also linked more walking and cycling to higher overall levels of physical activity.
The study does not calculate the overall percentage difference in levels of obesity and diabetes between places with the highest and lowest levels of walking and cycling. Nevertheless, Pucher said readers could calculate those numbers and find other statistics by examining research data.
In the big picture, the study results suggest that a big part of the gaps between American states and cities concerning health can be explained by differences in levels of walking and cycling, Pucher said.
While the link between more exercise and less obesity might seem obvious, he said there is a need for more scientific evidence to back it up. “As obvious as it is,” he said, “it’s shocking that Americans don’t want to do anything about it. It’s amazing how unconcerned most Americans are about this.”
Lawrence Frank, an associate professor who studies transportation at the University of British Columbia, said the study findings reflect the results of previous research that shows the effects of exercise (or the lack of it) on health.
“Physical activity is crucial,” Frank said. “If we keep designing communities in ways that make driving the more rational choice, we can expect health care costs to go up and quality of life to go down.”
Moderate drinking: Health benefits or not?
Ω
-There is disagreement about the health benefits of moderate drinking.
-A new study has examined drinking and mortality during a 20-year period.
-Findings confirm an association between moderate drinking and reduced mortality among older adults.
While moderate drinking – one to less than three drinks per day – is linked to a decrease in mortality in middle-aged and older adults, there is also concern that the health benefits of moderate drinking have been overestimated. A new study of the association between drinking and mortality during a 20-year period, which controlled for confounding factors such as previous problem drinking, confirms an association of moderate drinking and reduced mortality among older adults.
Results will be published in the November 2010 issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View.
"Although alcohol misuse is linked to many medical conditions, considerable epidemiological evidence indicates that moderate alcohol use is related to reduced total mortality," explained Charles J. Holahan, a professor in the department of psychology at The University of Texas at Austin and corresponding author for the study. "We expected that a substantial part of the health benefits associated with moderating drinking were due to confounding factors associated with alcohol abstention. For example, abstainers may include former problem drinkers with health problems and individuals who are atypical in terms of sociodemographic and social-behavioral factors that may increase health risk."
"None of the studies that have examined the association of drinking and mortality and cardiovascular disease have been experimental studies in which a group of people was randomly chosen to drink a particular amount of alcohol or to not drink alcohol," observed Alison A. Moore, professor of medicine and psychiatry in the David Geffen School of Medicine at the University of California, Los Angeles. "All have been observational studies, meaning those in which persons who consume varying amounts of alcohol are compared with those who don't. Because conditions in these observational studies are not controlled and the characteristics of persons who choose to drink varying amounts of alcohol or not differ quite a bit, it is impossible to prove that alcohol consumption causes reduced risks for coronary heart disease, diabetes or mortality."
For this study, using data gathered from a larger study of late-life patterns of drinking and related problems, researchers followed 1,824 older adults (1,142 men, 682 women) between the ages of 55 and 65 years of age – who were former or current drinkers – for 20 years. The information collected included: daily alcohol consumption, sociodemographic factors, former problem-drinking status, health factors, and social behavioral factors. Death was confirmed primarily by a death certificate.
"Controlling only for age and gender, mortality was highest among abstainers and heavy drinkers and lowest in moderate drinkers," said Holahan. "Controlling for former problem drinking status, existing health problems, and key sociodemographic and social-behavioral factors substantially reduced the mortality effect for abstainers compared to moderate drinkers. However, even after adjusting for all covariates, abstainers and heavy drinkers continued to show increased mortality risks of 49 percent and 42 percent, respectively, compared to moderate drinkers."
"In other words, the association of moderate drinking and reduced mortality among older adults is reduced but still present when taking into consideration factors that affect both alcohol consumption and mortality," said Moore. "For example, socioeconomic status has been a consistent factor in the link between alcohol consumption and mortality. That is, those with higher income and/or education are less likely to be abstainers and to die."
Thus, the health benefits of moderate drinking ae complicated because a number of underlying health risks are correlated with later life abstention, Holahan noted.
"Our findings demonstrate that abstainers were significantly more likely to have had prior drinking problems, to be obese, and to smoke cigarettes than moderate drinkers and scored significantly higher than moderate drinkers on health problems, depressive symptoms, and avoidance coping," he said. "In addition, abstainers were significantly lower than moderate drinkers on socioeconomic status, physical activity, number of close friends, and quality of friend support and significantly less likely to be married than moderate drinkers. Moreover, all of these factors that were associated with abstention significantly predicted mortality."
Both Holahan and Moore reiterated that any health benefits are linked to moderation. "Older persons drinking alcohol should remember that consuming more than two drinks a day exceeds recommended alcohol consumption guidelines in the U.S. and is associated with increased falls, a higher risk of alcohol use problems, and potential adverse interactions with medications," said Holahan. "Moreover, nondrinkers should not start drinking to try to enhance their health, and individuals who are or plan to become pregnant, or have alcohol problems or medical conditions that could be worsened by alcohol should not drink."
-There is disagreement about the health benefits of moderate drinking.
-A new study has examined drinking and mortality during a 20-year period.
-Findings confirm an association between moderate drinking and reduced mortality among older adults.
While moderate drinking – one to less than three drinks per day – is linked to a decrease in mortality in middle-aged and older adults, there is also concern that the health benefits of moderate drinking have been overestimated. A new study of the association between drinking and mortality during a 20-year period, which controlled for confounding factors such as previous problem drinking, confirms an association of moderate drinking and reduced mortality among older adults.
Results will be published in the November 2010 issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View.
"Although alcohol misuse is linked to many medical conditions, considerable epidemiological evidence indicates that moderate alcohol use is related to reduced total mortality," explained Charles J. Holahan, a professor in the department of psychology at The University of Texas at Austin and corresponding author for the study. "We expected that a substantial part of the health benefits associated with moderating drinking were due to confounding factors associated with alcohol abstention. For example, abstainers may include former problem drinkers with health problems and individuals who are atypical in terms of sociodemographic and social-behavioral factors that may increase health risk."
"None of the studies that have examined the association of drinking and mortality and cardiovascular disease have been experimental studies in which a group of people was randomly chosen to drink a particular amount of alcohol or to not drink alcohol," observed Alison A. Moore, professor of medicine and psychiatry in the David Geffen School of Medicine at the University of California, Los Angeles. "All have been observational studies, meaning those in which persons who consume varying amounts of alcohol are compared with those who don't. Because conditions in these observational studies are not controlled and the characteristics of persons who choose to drink varying amounts of alcohol or not differ quite a bit, it is impossible to prove that alcohol consumption causes reduced risks for coronary heart disease, diabetes or mortality."
For this study, using data gathered from a larger study of late-life patterns of drinking and related problems, researchers followed 1,824 older adults (1,142 men, 682 women) between the ages of 55 and 65 years of age – who were former or current drinkers – for 20 years. The information collected included: daily alcohol consumption, sociodemographic factors, former problem-drinking status, health factors, and social behavioral factors. Death was confirmed primarily by a death certificate.
"Controlling only for age and gender, mortality was highest among abstainers and heavy drinkers and lowest in moderate drinkers," said Holahan. "Controlling for former problem drinking status, existing health problems, and key sociodemographic and social-behavioral factors substantially reduced the mortality effect for abstainers compared to moderate drinkers. However, even after adjusting for all covariates, abstainers and heavy drinkers continued to show increased mortality risks of 49 percent and 42 percent, respectively, compared to moderate drinkers."
"In other words, the association of moderate drinking and reduced mortality among older adults is reduced but still present when taking into consideration factors that affect both alcohol consumption and mortality," said Moore. "For example, socioeconomic status has been a consistent factor in the link between alcohol consumption and mortality. That is, those with higher income and/or education are less likely to be abstainers and to die."
Thus, the health benefits of moderate drinking ae complicated because a number of underlying health risks are correlated with later life abstention, Holahan noted.
"Our findings demonstrate that abstainers were significantly more likely to have had prior drinking problems, to be obese, and to smoke cigarettes than moderate drinkers and scored significantly higher than moderate drinkers on health problems, depressive symptoms, and avoidance coping," he said. "In addition, abstainers were significantly lower than moderate drinkers on socioeconomic status, physical activity, number of close friends, and quality of friend support and significantly less likely to be married than moderate drinkers. Moreover, all of these factors that were associated with abstention significantly predicted mortality."
Both Holahan and Moore reiterated that any health benefits are linked to moderation. "Older persons drinking alcohol should remember that consuming more than two drinks a day exceeds recommended alcohol consumption guidelines in the U.S. and is associated with increased falls, a higher risk of alcohol use problems, and potential adverse interactions with medications," said Holahan. "Moreover, nondrinkers should not start drinking to try to enhance their health, and individuals who are or plan to become pregnant, or have alcohol problems or medical conditions that could be worsened by alcohol should not drink."
Monday, August 23, 2010
Bottled tea beverages may contain fewer polyphenols than brewed tea
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The first measurements of healthful antioxidant levels in commercial bottled tea beverages has concluded that health-conscious consumers may not be getting what they pay for: healthful doses of those antioxidants, or "poylphenols," that may ward off a range of diseases.
Scientists reported here today at the 240th National Meeting of the American Chemical Society (ACS) that many of the increasingly popular beverages included in their study, beverages that account for $1 billion in annual sales in the United States alone, contain fewer polyphenols than a single cup of home-brewed green or black tea. Some contain such small amounts that consumers would have to drink 20 bottles to get the polyphenols present in one cup of tea.
"Consumers understand very well the concept of the health benefits from drinking tea or consuming other tea products," said Shiming Li, Ph.D., who reported on the new study with Professor Chi-Tang Ho and his colleagues. "However, there is a huge gap between the perception that tea consumption is healthy and the actual amount of the healthful nutrients — polyphenols — found in bottled tea beverages. Our analysis of tea beverages found that the polyphenol content is extremely low."
Li pointed out that in addition to the low polyphenol content, bottled commercial tea contains other substances, including large amounts of sugar and the accompanying calories that health-conscious consumers may be trying to avoid. He is an analytical and natural product chemist at WellGen, Inc., a biotechnology company in North Brunswick, N.J., that discovers and develops medical foods for patients with diseases, including a proprietary black tea product that will be marketed for its anti-inflammatory benefits, which are due in part to a high polyphenol content.
Li and colleagues measured the level of polyphenols — a group of natural antioxidants linked to anti-cancer, anti-inflammatory, and anti-diabetic properties — of six brands of tea purchased from supermarkets. Half of them contained what Li characterized as "virtually no" antioxidants. The rest had small amounts of polyphenols that Li said probably would carry little health benefit, especially when considering the high sugar intake from tea beverages.
"Someone would have to drink bottle after bottle of these teas in some cases to receive health benefits," he said. "I was surprised at the low polyphenol content. I didn't expect it to be at such a low level."
The six teas Li analyzed contained 81, 43, 40, 13, 4, and 3 milligrams (mg.) of polyphenols per 16-ounce bottle. One average cup of home-brewed green or black tea, which costs only a few cents, contains 50-150 mg. of polyphenols.
After water, tea is the world's most widely consumed beverage. Tea sales in the United States have quadrupled since 1990 and now total about $7 billion annually. The major reason: Scientific evidence that the polyphenols and other antioxidants in tea may reduce the risk of cancer, heart disease, and other afflictions.
Li said that some manufacturers do list polyphenol content on the bottle label. But the amounts may be incorrect because there are no industry or government standards or guidelines for measuring and listing the polyphenolic compounds in a given product. A regular tea bag, for example, weighs about 2.2 grams and could contain as much as 175 mg. of polyphenols, Li said. But polyphenols degrade and disappear as the tea bag is steeped in hot water. The polyphenol content also may vary as manufacturers change their processes, including the quantity and quality of tea used to prepare a batch and the tea brewing time.
"Polyphenols are bitter and astringent, but to target as many consumers as they can, manufacturers want to keep the bitterness and astringency at a minimum," Li explained. "The simplest way is to add less tea, which makes the tea polyphenol content low but tastes smoother and sweeter."
Li used a standard laboratory technique, termed high-performance liquid chromatography (HPLC), to make what he described as the first measurements of polyphenols in bottled tea beverages. He hopes the research will encourage similar use of HPLC by manufacturers and others to provide consumers with better nutritional information.
The first measurements of healthful antioxidant levels in commercial bottled tea beverages has concluded that health-conscious consumers may not be getting what they pay for: healthful doses of those antioxidants, or "poylphenols," that may ward off a range of diseases.
Scientists reported here today at the 240th National Meeting of the American Chemical Society (ACS) that many of the increasingly popular beverages included in their study, beverages that account for $1 billion in annual sales in the United States alone, contain fewer polyphenols than a single cup of home-brewed green or black tea. Some contain such small amounts that consumers would have to drink 20 bottles to get the polyphenols present in one cup of tea.
"Consumers understand very well the concept of the health benefits from drinking tea or consuming other tea products," said Shiming Li, Ph.D., who reported on the new study with Professor Chi-Tang Ho and his colleagues. "However, there is a huge gap between the perception that tea consumption is healthy and the actual amount of the healthful nutrients — polyphenols — found in bottled tea beverages. Our analysis of tea beverages found that the polyphenol content is extremely low."
Li pointed out that in addition to the low polyphenol content, bottled commercial tea contains other substances, including large amounts of sugar and the accompanying calories that health-conscious consumers may be trying to avoid. He is an analytical and natural product chemist at WellGen, Inc., a biotechnology company in North Brunswick, N.J., that discovers and develops medical foods for patients with diseases, including a proprietary black tea product that will be marketed for its anti-inflammatory benefits, which are due in part to a high polyphenol content.
Li and colleagues measured the level of polyphenols — a group of natural antioxidants linked to anti-cancer, anti-inflammatory, and anti-diabetic properties — of six brands of tea purchased from supermarkets. Half of them contained what Li characterized as "virtually no" antioxidants. The rest had small amounts of polyphenols that Li said probably would carry little health benefit, especially when considering the high sugar intake from tea beverages.
"Someone would have to drink bottle after bottle of these teas in some cases to receive health benefits," he said. "I was surprised at the low polyphenol content. I didn't expect it to be at such a low level."
The six teas Li analyzed contained 81, 43, 40, 13, 4, and 3 milligrams (mg.) of polyphenols per 16-ounce bottle. One average cup of home-brewed green or black tea, which costs only a few cents, contains 50-150 mg. of polyphenols.
After water, tea is the world's most widely consumed beverage. Tea sales in the United States have quadrupled since 1990 and now total about $7 billion annually. The major reason: Scientific evidence that the polyphenols and other antioxidants in tea may reduce the risk of cancer, heart disease, and other afflictions.
Li said that some manufacturers do list polyphenol content on the bottle label. But the amounts may be incorrect because there are no industry or government standards or guidelines for measuring and listing the polyphenolic compounds in a given product. A regular tea bag, for example, weighs about 2.2 grams and could contain as much as 175 mg. of polyphenols, Li said. But polyphenols degrade and disappear as the tea bag is steeped in hot water. The polyphenol content also may vary as manufacturers change their processes, including the quantity and quality of tea used to prepare a batch and the tea brewing time.
"Polyphenols are bitter and astringent, but to target as many consumers as they can, manufacturers want to keep the bitterness and astringency at a minimum," Li explained. "The simplest way is to add less tea, which makes the tea polyphenol content low but tastes smoother and sweeter."
Li used a standard laboratory technique, termed high-performance liquid chromatography (HPLC), to make what he described as the first measurements of polyphenols in bottled tea beverages. He hopes the research will encourage similar use of HPLC by manufacturers and others to provide consumers with better nutritional information.
Eating berries may activate the brain's natural housekeeper for healthy aging
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Scientists today reported the first evidence that eating blueberries, strawberries, and acai berries may help the aging brain stay healthy in a crucial but previously unrecognized way. Their study, presented at the 240th National Meeting of the American Chemical Society (ACS), concluded that berries, and possibly walnuts, activate the brain's natural "housekeeper" mechanism, which cleans up and recycles toxic proteins linked to age-related memory loss and other mental decline.
Shibu Poulose, Ph.D., who presented the report, said previous research suggested that one factor involved in aging is a steady decline in the body's ability to protect itself against inflammation and oxidative damage. This leaves people vulnerable to degenerative brain diseases, heart disease, cancer, and other age-related disorders.
"The good news is that natural compounds called polyphenolics found in fruits, vegetables and nuts have an antioxidant and anti-inflammatory effect that may protect against age-associated decline," said Poulose, who is with the U. S. Department of Agriculture-Agricultural Research Service (USDA-ARS) Human Nutrition Research Center on Aging in Boston. Poulose did the research with James Joseph, Ph.D., who died June 1. Joseph, who headed the laboratory, pioneered research on the role of antioxidants in fruits and nuts in preventing age-related cognitive decline.
Their past studies, for instance, showed that old laboratory rats fed for two months on diets containing 2 percent high-antioxidant strawberry, blueberry, or blackberry extract showed a reversal of age-related deficits in nerve function and behavior that involves learning and remembering.
In the new research, Poulose and Joseph focused on another reason why nerve function declines with aging. It involves a reduction in the brain's natural house-cleaning process. Cells called microglia are the housekeepers. In a process called autophagy, they remove and recycle biochemical debris that otherwise would interfere with brain function.
"But in aging, microglia fail to do their work, and debris builds up," Poulose explained. "In addition, the microglia become over-activated and actually begin to damage healthy cells in the brain. Our research suggests that the polyphenolics in berries have a rescuing effect. They seem to restore the normal housekeeping function. These findings are the first to show these effects of berries."
The findings emerged from research in which Joseph and Poulose have tried to detail factors involved in the aging brain's loss of normal housekeeping activity. Using cultures of mouse brain cells, they found that extracts of berries inhibited the action of a protein that shuts down the autophagy process.
Poulose said the study provides further evidence to eat foods rich in polyphenolics. Although berries and walnuts are rich sources, many other fruits and vegetables contain these chemicals ― especially those with deep red, orange, or blue colors. Those colors come from pigments termed anthocyanins that are good antioxidants. He emphasized the importance of consuming the whole fruit, which contains the full range of hundreds of healthful chemicals. Frozen berries, which are available year round, also are excellent sources of polyphenolics, he added.
Scientists today reported the first evidence that eating blueberries, strawberries, and acai berries may help the aging brain stay healthy in a crucial but previously unrecognized way. Their study, presented at the 240th National Meeting of the American Chemical Society (ACS), concluded that berries, and possibly walnuts, activate the brain's natural "housekeeper" mechanism, which cleans up and recycles toxic proteins linked to age-related memory loss and other mental decline.
Shibu Poulose, Ph.D., who presented the report, said previous research suggested that one factor involved in aging is a steady decline in the body's ability to protect itself against inflammation and oxidative damage. This leaves people vulnerable to degenerative brain diseases, heart disease, cancer, and other age-related disorders.
"The good news is that natural compounds called polyphenolics found in fruits, vegetables and nuts have an antioxidant and anti-inflammatory effect that may protect against age-associated decline," said Poulose, who is with the U. S. Department of Agriculture-Agricultural Research Service (USDA-ARS) Human Nutrition Research Center on Aging in Boston. Poulose did the research with James Joseph, Ph.D., who died June 1. Joseph, who headed the laboratory, pioneered research on the role of antioxidants in fruits and nuts in preventing age-related cognitive decline.
Their past studies, for instance, showed that old laboratory rats fed for two months on diets containing 2 percent high-antioxidant strawberry, blueberry, or blackberry extract showed a reversal of age-related deficits in nerve function and behavior that involves learning and remembering.
In the new research, Poulose and Joseph focused on another reason why nerve function declines with aging. It involves a reduction in the brain's natural house-cleaning process. Cells called microglia are the housekeepers. In a process called autophagy, they remove and recycle biochemical debris that otherwise would interfere with brain function.
"But in aging, microglia fail to do their work, and debris builds up," Poulose explained. "In addition, the microglia become over-activated and actually begin to damage healthy cells in the brain. Our research suggests that the polyphenolics in berries have a rescuing effect. They seem to restore the normal housekeeping function. These findings are the first to show these effects of berries."
The findings emerged from research in which Joseph and Poulose have tried to detail factors involved in the aging brain's loss of normal housekeeping activity. Using cultures of mouse brain cells, they found that extracts of berries inhibited the action of a protein that shuts down the autophagy process.
Poulose said the study provides further evidence to eat foods rich in polyphenolics. Although berries and walnuts are rich sources, many other fruits and vegetables contain these chemicals ― especially those with deep red, orange, or blue colors. Those colors come from pigments termed anthocyanins that are good antioxidants. He emphasized the importance of consuming the whole fruit, which contains the full range of hundreds of healthful chemicals. Frozen berries, which are available year round, also are excellent sources of polyphenolics, he added.
Alcohol intake increases certain types of breast cancer
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Alcohol increases the risk of lobular and hormone receptor-positive breast cancer, but not necessarily invasive ductal carcinomas, according to a study published August 23 online in The Journal of the National Cancer Institute.
Although alcohol intake is an established risk factor for overall breast cancer, few studies have looked at the relationship between alcohol use and breast cancer risk by subtype of breast cancer. While some studies have shown alcohol use is more strongly related to risk of hormone receptor-positive (estrogen receptor and/or progesterone receptor-positive) breast cancer, not many have looked at breast cancer risk by histology, or whether a tumor is ductal—in the milk ducts—or lobular—in the milk-producing lobules.
To understand how alcohol may influence sub-types of breast cancer, Christopher I. Li, M.D., Ph.D., and colleagues at Fred Hutchinson Cancer Research Center conducted an observational study of a subset of patients in the Women's Health Initiative (WHI) study, conducted between 1993 and 1998, which included 87,724 postmenopausal women aged 50-79 years.
The researchers looked at the following data from the 2,944 women in the WHI study who developed invasive breast cancer: tumor subtypes and hormone status, alcohol consumption, demographic and lifestyle characteristics, family history of diseases and reproductive history. Women were categorized as those who never drank, those who formerly drank and those who currently drank. Drinkers were grouped into six categories according to the average number of drinks per week, starting from less than one drink per week to more than 14 drinks per week.
The researchers found that alcohol use is more strongly related to the risk of lobular carcinoma than ductal carcinoma, and more strongly related to hormone-receptor- positive breast cancer than hormone-receptor-negative breast cancer. These results confirm previous findings of an association of alcohol consumption with hormone-positive breast cancer risk, as well as three previous case control studies that identified a stronger association of alcohol with lobular carcinoma. The risks observed did not vary by the type of alcohol women consumed.
The authors write, "We found that women who drank one or more drinks per day had about double the risk of lobular type breast cancer, but no increase in their risk of ductal type breast cancer. It is important to note that ductal cancer is much more common than lobular cancer accounting for about 70 percent of all breast cancers whereas lobular cancer accounts for only about 10-15 percent of cases."
The study's primary limitation, the authors say, is that alcohol usage was only assessed at the beginning of the study, so the researchers had no information on womens' past alcohol usage, nor their subsequent usage.
Alcohol increases the risk of lobular and hormone receptor-positive breast cancer, but not necessarily invasive ductal carcinomas, according to a study published August 23 online in The Journal of the National Cancer Institute.
Although alcohol intake is an established risk factor for overall breast cancer, few studies have looked at the relationship between alcohol use and breast cancer risk by subtype of breast cancer. While some studies have shown alcohol use is more strongly related to risk of hormone receptor-positive (estrogen receptor and/or progesterone receptor-positive) breast cancer, not many have looked at breast cancer risk by histology, or whether a tumor is ductal—in the milk ducts—or lobular—in the milk-producing lobules.
To understand how alcohol may influence sub-types of breast cancer, Christopher I. Li, M.D., Ph.D., and colleagues at Fred Hutchinson Cancer Research Center conducted an observational study of a subset of patients in the Women's Health Initiative (WHI) study, conducted between 1993 and 1998, which included 87,724 postmenopausal women aged 50-79 years.
The researchers looked at the following data from the 2,944 women in the WHI study who developed invasive breast cancer: tumor subtypes and hormone status, alcohol consumption, demographic and lifestyle characteristics, family history of diseases and reproductive history. Women were categorized as those who never drank, those who formerly drank and those who currently drank. Drinkers were grouped into six categories according to the average number of drinks per week, starting from less than one drink per week to more than 14 drinks per week.
The researchers found that alcohol use is more strongly related to the risk of lobular carcinoma than ductal carcinoma, and more strongly related to hormone-receptor- positive breast cancer than hormone-receptor-negative breast cancer. These results confirm previous findings of an association of alcohol consumption with hormone-positive breast cancer risk, as well as three previous case control studies that identified a stronger association of alcohol with lobular carcinoma. The risks observed did not vary by the type of alcohol women consumed.
The authors write, "We found that women who drank one or more drinks per day had about double the risk of lobular type breast cancer, but no increase in their risk of ductal type breast cancer. It is important to note that ductal cancer is much more common than lobular cancer accounting for about 70 percent of all breast cancers whereas lobular cancer accounts for only about 10-15 percent of cases."
The study's primary limitation, the authors say, is that alcohol usage was only assessed at the beginning of the study, so the researchers had no information on womens' past alcohol usage, nor their subsequent usage.
Increased Risk of Stroke Associated With Nonsteroidal Anti-Inflammatory Drugs. A Nationwide Case–Crossover Study
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Background and Purpose—Limited studies assessed cerebrovascular safety of individual nonsteroidal anti-inflammatory drugs (NSAIDs). We evaluated the risk of ischemic and hemorrhagic stroke associated with short-term use of selective and nonselective NSAIDs in a Chinese population with a high incidence of stroke.
Methods—A retrospective case–crossover study was conducted by analyzing the Taiwan National Health Insurance Database. We identified all ischemic and hemorrhagic stroke patients in 2006, aged 20 years, based on International Classification of Diseases, 9th Revision, Clinical Modification diagnosis codes from inpatient claims and defined the index date as the date of hospitalization. For each patient, we defined case period as 1 to 30 days before the index date and control period as 91 to 120 days before the index date. A pharmacy prescription database was searched for NSAID use during the case and control periods. We calculated adjusted ORs and their 95% CIs with a conditional logistic regression model.
Results—A total of 28 424 patients with ischemic stroke and 9456 patients with hemorrhagic stroke were included. For ischemic stroke, a modest increased risk was evident for all oral NSAIDs with adjusted ORs (95% CI) ranging from1.20 (1.00 to 1.44) for celecoxib to 1.90 (1.39 to 2.60) for ketorolac. For hemorrhagic stroke, oral ketorolac was associated with a significantly higher risk with OR of 2.69 (1.56 to 4.66). Significantly increased risk was found for parenteral NSAIDs, in particular ketorolac, with an OR of 3.92 (3.25 to 4.72) for ischemic stroke and 5.98 (4.40 to 8.13) for hemorrhagic stroke.
Conclusions—Use of selective and nonselective NSAIDs was associated with an increased risk of both ischemic and hemorrhagic stroke, strikingly high for parenteral ketorolac.
Background and Purpose—Limited studies assessed cerebrovascular safety of individual nonsteroidal anti-inflammatory drugs (NSAIDs). We evaluated the risk of ischemic and hemorrhagic stroke associated with short-term use of selective and nonselective NSAIDs in a Chinese population with a high incidence of stroke.
Methods—A retrospective case–crossover study was conducted by analyzing the Taiwan National Health Insurance Database. We identified all ischemic and hemorrhagic stroke patients in 2006, aged 20 years, based on International Classification of Diseases, 9th Revision, Clinical Modification diagnosis codes from inpatient claims and defined the index date as the date of hospitalization. For each patient, we defined case period as 1 to 30 days before the index date and control period as 91 to 120 days before the index date. A pharmacy prescription database was searched for NSAID use during the case and control periods. We calculated adjusted ORs and their 95% CIs with a conditional logistic regression model.
Results—A total of 28 424 patients with ischemic stroke and 9456 patients with hemorrhagic stroke were included. For ischemic stroke, a modest increased risk was evident for all oral NSAIDs with adjusted ORs (95% CI) ranging from1.20 (1.00 to 1.44) for celecoxib to 1.90 (1.39 to 2.60) for ketorolac. For hemorrhagic stroke, oral ketorolac was associated with a significantly higher risk with OR of 2.69 (1.56 to 4.66). Significantly increased risk was found for parenteral NSAIDs, in particular ketorolac, with an OR of 3.92 (3.25 to 4.72) for ischemic stroke and 5.98 (4.40 to 8.13) for hemorrhagic stroke.
Conclusions—Use of selective and nonselective NSAIDs was associated with an increased risk of both ischemic and hemorrhagic stroke, strikingly high for parenteral ketorolac.
Polyphenol antioxidants inhibit iron absorption
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Health benefits from polyphenol antioxidants — substances found in many fruits and vegetables — may come at a cost to some people. Penn State nutritional scientists found that eating certain polyphenols decreased the amount of iron the body absorbs, which can increase the risk of developing an iron deficiency.
"Polyphenols have been known to have many beneficial effects for human health, such as preventing or delaying certain types of cancer, enhancing bone metabolism and improving bone mineral density, and decreasing risk of heart disease," said Okhee Han, assistant professor of nutritional sciences. "But so far, not many people have thought about whether or not polyphenols affect nutrient absorption."
The researchers, led by Han, studied the effects of eating grape seed extract and epigallocatechin-3-gallate (EGCG) found in green tea. They used cells from the intestine — where iron absorption takes place — to assess the polyphenols' effect and found that polyphenols bind to iron in the intestinal cells, forming a non-transportable complex. This iron-polyphenol complex cannot enter the blood stream. Instead, it is excreted in the feces when cells are sloughed off and replaced.
Iron is necessary to carry oxygen from the lungs throughout the body and for other cellular functions. People already at risk for iron deficiency increase that risk if they consume high amounts of grape seed extract or EGCG.
"Iron deficiency is the most prevalent nutrient deficiency in the world, especially in developing countries where meats are not plentiful," said Han. "People at high risk of developing iron deficiency — such as pregnant women and young children — should be aware of what polyphenols they are consuming."
Han and her colleagues looked at the heme form of iron found in meats, poultry, and fish. Last year, they performed similar research with non-heme iron found in plants. They published the results of their study on grape seed extract and EGCG in the Journal of Nutrition, showing that eating polyphenols decreased iron absorption.
Both grape seed extract and EGCG are sold in extract form. The results of these studies suggest that consumers should be cautious if using these products.
Han and her colleagues recently received a grant from the National Institutes of Health, National Center for Complementary and Alternative Medicine to expand this research. They will conduct animal studies and eventually hope to do human studies as well. Other authors on the paper include Qianyi Ma, graduate student in nutritional sciences, and Eun-Young Kim, research assistant in nutritional sciences.
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Health benefits from polyphenol antioxidants — substances found in many fruits and vegetables — may come at a cost to some people. Penn State nutritional scientists found that eating certain polyphenols decreased the amount of iron the body absorbs, which can increase the risk of developing an iron deficiency.
"Polyphenols have been known to have many beneficial effects for human health, such as preventing or delaying certain types of cancer, enhancing bone metabolism and improving bone mineral density, and decreasing risk of heart disease," said Okhee Han, assistant professor of nutritional sciences. "But so far, not many people have thought about whether or not polyphenols affect nutrient absorption."
The researchers, led by Han, studied the effects of eating grape seed extract and epigallocatechin-3-gallate (EGCG) found in green tea. They used cells from the intestine — where iron absorption takes place — to assess the polyphenols' effect and found that polyphenols bind to iron in the intestinal cells, forming a non-transportable complex. This iron-polyphenol complex cannot enter the blood stream. Instead, it is excreted in the feces when cells are sloughed off and replaced.
Iron is necessary to carry oxygen from the lungs throughout the body and for other cellular functions. People already at risk for iron deficiency increase that risk if they consume high amounts of grape seed extract or EGCG.
"Iron deficiency is the most prevalent nutrient deficiency in the world, especially in developing countries where meats are not plentiful," said Han. "People at high risk of developing iron deficiency — such as pregnant women and young children — should be aware of what polyphenols they are consuming."
Han and her colleagues looked at the heme form of iron found in meats, poultry, and fish. Last year, they performed similar research with non-heme iron found in plants. They published the results of their study on grape seed extract and EGCG in the Journal of Nutrition, showing that eating polyphenols decreased iron absorption.
Both grape seed extract and EGCG are sold in extract form. The results of these studies suggest that consumers should be cautious if using these products.
Han and her colleagues recently received a grant from the National Institutes of Health, National Center for Complementary and Alternative Medicine to expand this research. They will conduct animal studies and eventually hope to do human studies as well. Other authors on the paper include Qianyi Ma, graduate student in nutritional sciences, and Eun-Young Kim, research assistant in nutritional sciences.
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Antagonistic people may increase heart attack, stroke risk
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Study highlights:
* Antagonistic people have greater thickening of neck artery walls than agreeable people, increasing the risk of cardiovascular disease.
* Those deemed the least agreeable had a 40 percent increased risk of artery narrowing compared to those who were the most agreeable.
Antagonistic people, particularly those who are competitive and aggressive, may be increasing their risk of heart attack or stroke, researchers report in Hypertension: Journal of the American Heart Association.
Researchers for the U.S. National Institute on Aging (NIA), a component of the National Institutes of Health (NIH), studied 5,614 Italians in four villages and found that those who scored high for antagonistic traits on a standard personality test had greater thickening of the neck (carotid) arteries compared to people who were more agreeable. Thickness of neck artery walls is a risk factor for heart attack and stroke.
Three years later, those who scored higher on antagonism or low agreeableness — especially those who were manipulative and quick to express anger — continued to have thickening of their artery walls. These traits also predicted greater progression of arterial thickening.
Those who scored in the bottom 10 percent of agreeableness and were the most antagonistic had about a 40 percent increased risk for elevated intima-media thickness, a measure of arterial wall thickness. The effect on artery walls was similar to having metabolic syndrome — a known risk factor for cardiovascular disease.
“People who tend to be competitive and more willing to fight for their own self interest have thicker arterial walls, which is a risk factor for cardiovascular disease,” said Angelina Sutin, Ph.D., lead author of the study and a postdoctoral fellow with the National Institute on Aging, NIH, in Baltimore, Md. “Agreeable people tend to be trusting, straightforward and show concern for others, while people who score high on antagonism tend to be distrustful, skeptical and at the extreme cynical, manipulative, self-centered, arrogant and quick to express anger.”
The SardiNIA Study of Aging, supported by the NIA, was conducted in the Sardinia region of Italy. Participants’ ages ranged from 14 to 94 years (average 42) and 58 percent were female. They answered a standard personality questionnaire, which included six facets of agreeableness: trust, straightforwardness, altruism, compliance, modesty and tender mindedness.
Researchers used ultrasound to determine the intima-media thickness of the carotid arteries in the neck at five points. Participants also were screened for other risk factors for cardiovascular disease such as high blood pressure, cholesterol levels, triglycerides, fasting glucose and diabetes.
In general, men had more thickening of the artery walls. But if women were antagonistic, their risk quickly caught up with the men, Sutin said. “Women who scored high on antagonism related traits tended to close the gap, developing arterial thickness similar to antagonistic men. Whereas women with agreeable traits had much thinner arterial walls than men with agreeable traits, antagonism had a much stronger association with arterial thickness in women.”
Though thickening of the artery walls is a sign of age, young people with antagonistic traits already had thickening of the artery wall, she said. Lifestyle factors may contribute, but the association persisted after controlling for risk factors such as smoking.
Physicians may want to examine antagonism and other facets of personality traits when considering risk factors such as smoking, weight, cholesterol levels and diabetes, Sutin said. The results of this study could also help determine who might benefit from targeted interventions such as providing coping mechanisms and anger management.
“People may learn to control their anger and learn ways to express anger in more socially acceptable ways,” Sutin said.
The findings may apply to others in the world, whether they live in smaller towns or cosmopolitan areas, she said. “This may not be unique to Italians.”
Study highlights:
* Antagonistic people have greater thickening of neck artery walls than agreeable people, increasing the risk of cardiovascular disease.
* Those deemed the least agreeable had a 40 percent increased risk of artery narrowing compared to those who were the most agreeable.
Antagonistic people, particularly those who are competitive and aggressive, may be increasing their risk of heart attack or stroke, researchers report in Hypertension: Journal of the American Heart Association.
Researchers for the U.S. National Institute on Aging (NIA), a component of the National Institutes of Health (NIH), studied 5,614 Italians in four villages and found that those who scored high for antagonistic traits on a standard personality test had greater thickening of the neck (carotid) arteries compared to people who were more agreeable. Thickness of neck artery walls is a risk factor for heart attack and stroke.
Three years later, those who scored higher on antagonism or low agreeableness — especially those who were manipulative and quick to express anger — continued to have thickening of their artery walls. These traits also predicted greater progression of arterial thickening.
Those who scored in the bottom 10 percent of agreeableness and were the most antagonistic had about a 40 percent increased risk for elevated intima-media thickness, a measure of arterial wall thickness. The effect on artery walls was similar to having metabolic syndrome — a known risk factor for cardiovascular disease.
“People who tend to be competitive and more willing to fight for their own self interest have thicker arterial walls, which is a risk factor for cardiovascular disease,” said Angelina Sutin, Ph.D., lead author of the study and a postdoctoral fellow with the National Institute on Aging, NIH, in Baltimore, Md. “Agreeable people tend to be trusting, straightforward and show concern for others, while people who score high on antagonism tend to be distrustful, skeptical and at the extreme cynical, manipulative, self-centered, arrogant and quick to express anger.”
The SardiNIA Study of Aging, supported by the NIA, was conducted in the Sardinia region of Italy. Participants’ ages ranged from 14 to 94 years (average 42) and 58 percent were female. They answered a standard personality questionnaire, which included six facets of agreeableness: trust, straightforwardness, altruism, compliance, modesty and tender mindedness.
Researchers used ultrasound to determine the intima-media thickness of the carotid arteries in the neck at five points. Participants also were screened for other risk factors for cardiovascular disease such as high blood pressure, cholesterol levels, triglycerides, fasting glucose and diabetes.
In general, men had more thickening of the artery walls. But if women were antagonistic, their risk quickly caught up with the men, Sutin said. “Women who scored high on antagonism related traits tended to close the gap, developing arterial thickness similar to antagonistic men. Whereas women with agreeable traits had much thinner arterial walls than men with agreeable traits, antagonism had a much stronger association with arterial thickness in women.”
Though thickening of the artery walls is a sign of age, young people with antagonistic traits already had thickening of the artery wall, she said. Lifestyle factors may contribute, but the association persisted after controlling for risk factors such as smoking.
Physicians may want to examine antagonism and other facets of personality traits when considering risk factors such as smoking, weight, cholesterol levels and diabetes, Sutin said. The results of this study could also help determine who might benefit from targeted interventions such as providing coping mechanisms and anger management.
“People may learn to control their anger and learn ways to express anger in more socially acceptable ways,” Sutin said.
The findings may apply to others in the world, whether they live in smaller towns or cosmopolitan areas, she said. “This may not be unique to Italians.”
Friday, August 20, 2010
Healthier protein-rich foods instead of red and processed meats may reduce heart disease risk in women
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American women who ate more protein-rich foods instead of red meat had a significantly lower risk of developing heart disease, according to a study reported in Circulation: Journal of the American Heart Association.
Eating more fresh red meat, processed red meat and high-fat dairy carried an increased risk of heart disease in the study. Women who had two servings per day of red meat compared to those who had half a serving per day had a 30 percent higher risk of developing coronary heart disease.
“Our study shows that making substitutes for red meat or minimizing the amount of red meat in the diet has important health benefits,” said Adam M. Bernstein, M.D., Sc.D., the study’s first author and post-doctoral research fellow in the Department of Nutrition at Harvard School of Public Health in Boston.
The data also showed that eating more servings of poultry, fish and nuts was significantly associated with a decreased risk of coronary heart disease. Compared to one serving each day of red meat, women who substituted other protein-rich foods experienced significantly lower risk of coronary heart disease:
30 percent lower risk with one serving each day of nuts
24 percent lower risk with one serving each day of fish
19 percent lower risk with one serving each day of poultry
13 percent lower risk with one serving each day of low-fat dairy products
“There are good protein-rich sources that do not involve red meat,” Bernstein said. “You don’t need to have hot dogs, hamburgers, bologna or pastrami, which are all fresh or processed meats.”
The study examined 84,136 women, 30 to 55 years old, in the Nurses’ Health Study over 26 years, from 1980 to 2006. The majority of women were Caucasian.
Researchers examined the medical history and lifestyles of these women, including diet, with questionnaires issued regularly throughout 26 years. Detailed dietary information included a 61-item food frequency questionnaire, which researchers later expanded to 116 food items.
Nurses were asked how often they had consumed a unit or portion of each food on average during the previous year. Nine possible responses included from “never” to “more than six times daily.”
The primary endpoint of the study was non-fatal heart attack and fatal coronary heart disease, from 1980 up to June 1, 2006. During that time, researchers documented 2,210 non-fatal heart attacks and 952 deaths from coronary heart disease.
The study differs from others in the field because the analysis has a 26-year follow-up, greater precision in dietary measurements due to a great number of cases and repeated dietary questionnaires. It also differs because of the emphasis on substitution patterns and substitution of other protein-rich foods for red meat.
“Although this study included only women, our overall knowledge of risk factors for heart disease suggests that the findings are likely to apply to men as well,” Bernstein said.
“Those who are concerned and want to reduce their risk of heart disease should consider replacing red meat with other protein-rich foods including fish, poultry, low-fat dairy products and nuts,” Bernstein said.
American women who ate more protein-rich foods instead of red meat had a significantly lower risk of developing heart disease, according to a study reported in Circulation: Journal of the American Heart Association.
Eating more fresh red meat, processed red meat and high-fat dairy carried an increased risk of heart disease in the study. Women who had two servings per day of red meat compared to those who had half a serving per day had a 30 percent higher risk of developing coronary heart disease.
“Our study shows that making substitutes for red meat or minimizing the amount of red meat in the diet has important health benefits,” said Adam M. Bernstein, M.D., Sc.D., the study’s first author and post-doctoral research fellow in the Department of Nutrition at Harvard School of Public Health in Boston.
The data also showed that eating more servings of poultry, fish and nuts was significantly associated with a decreased risk of coronary heart disease. Compared to one serving each day of red meat, women who substituted other protein-rich foods experienced significantly lower risk of coronary heart disease:
30 percent lower risk with one serving each day of nuts
24 percent lower risk with one serving each day of fish
19 percent lower risk with one serving each day of poultry
13 percent lower risk with one serving each day of low-fat dairy products
“There are good protein-rich sources that do not involve red meat,” Bernstein said. “You don’t need to have hot dogs, hamburgers, bologna or pastrami, which are all fresh or processed meats.”
The study examined 84,136 women, 30 to 55 years old, in the Nurses’ Health Study over 26 years, from 1980 to 2006. The majority of women were Caucasian.
Researchers examined the medical history and lifestyles of these women, including diet, with questionnaires issued regularly throughout 26 years. Detailed dietary information included a 61-item food frequency questionnaire, which researchers later expanded to 116 food items.
Nurses were asked how often they had consumed a unit or portion of each food on average during the previous year. Nine possible responses included from “never” to “more than six times daily.”
The primary endpoint of the study was non-fatal heart attack and fatal coronary heart disease, from 1980 up to June 1, 2006. During that time, researchers documented 2,210 non-fatal heart attacks and 952 deaths from coronary heart disease.
The study differs from others in the field because the analysis has a 26-year follow-up, greater precision in dietary measurements due to a great number of cases and repeated dietary questionnaires. It also differs because of the emphasis on substitution patterns and substitution of other protein-rich foods for red meat.
“Although this study included only women, our overall knowledge of risk factors for heart disease suggests that the findings are likely to apply to men as well,” Bernstein said.
“Those who are concerned and want to reduce their risk of heart disease should consider replacing red meat with other protein-rich foods including fish, poultry, low-fat dairy products and nuts,” Bernstein said.
Women who drink beer more likely to develop psoriasis
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Regular beer—but not light beer or other types of alcohol—appears to be associated with an increased risk of developing psoriasis, according to a report posted online today that will be published in the December print issue of Archives of Dermatology, one of the JAMA/Archives journals.
"Psoriasis is a common immune-mediated skin disease," the authors write as background information in the article. "The association between alcohol consumption and increased risk of psoriasis onset and psoriasis worsening has long been suspected. For example, individuals with psoriasis drink more alcohol than individuals without psoriasis, and alcohol intake may exacerbate psoriasis severity."
For other diseases, type of alcoholic beverage has been shown to influence risk—for instance, beer confers a larger risk for gout than wine or spirits. To evaluate the association between different types of alcohol and psoriasis risk, Abrar A. Qureshi, M.D., M.P.H., of Brigham and Women's Hospital and Harvard Medical School, Boston, assessed data from 82,869 women who were age 27 to 44 years in 1991. The women, participants in the Nurses' Health Study II, reported the amount and type of alcohol they consumed on biennial questionnaires. They also reported whether they had received a diagnosis of psoriasis.
Through 2005, 1,150 cases of psoriasis developed, 1,069 of which were used for analysis. Compared with women who did not drink alcohol, the risk of psoriasis was 72 percent greater among women who had an average of 2.3 drinks per week or more. When beverages were assessed by type, there was an association between non-light beer drinking and psoriasis, such that women who drank five or more beers per week had a risk for the condition that was 1.8 times higher. Light beer, red wine, white wine and liquor were not associated with psoriasis risk.
When only confirmed psoriasis cases—those in which women provided more details about their condition on a seven-item self-assessment—were considered, the risk for psoriasis was 2.3 times higher for women who drank five or more beers per week than women who did not drink beer.
"Non-light beer was the only alcoholic beverage that increased the risk for psoriasis, suggesting that certain non-alcoholic components of beer, which are not found in wine or liquor, may play an important role in new-onset psoriasis," the authors write. "One of these components may be the starch source used in making beer. Beer is one of the few non-distilled alcoholic beverages that use a starch source for fermentation, which is commonly barley." Barley and other starches contain gluten, to which some individuals with psoriasis show a sensitivity. Lower amounts of grain are used to make light beer as compared with non-light beer, potentially explaining why light beer was not associated with psoriasis risk, they note.
"Women with a high risk of psoriasis may consider avoiding higher intake of non-light beer," the authors conclude. "We suggest conducting further investigations into the potential mechanisms of non-light beer inducing new-onset psoriasis."
Regular beer—but not light beer or other types of alcohol—appears to be associated with an increased risk of developing psoriasis, according to a report posted online today that will be published in the December print issue of Archives of Dermatology, one of the JAMA/Archives journals.
"Psoriasis is a common immune-mediated skin disease," the authors write as background information in the article. "The association between alcohol consumption and increased risk of psoriasis onset and psoriasis worsening has long been suspected. For example, individuals with psoriasis drink more alcohol than individuals without psoriasis, and alcohol intake may exacerbate psoriasis severity."
For other diseases, type of alcoholic beverage has been shown to influence risk—for instance, beer confers a larger risk for gout than wine or spirits. To evaluate the association between different types of alcohol and psoriasis risk, Abrar A. Qureshi, M.D., M.P.H., of Brigham and Women's Hospital and Harvard Medical School, Boston, assessed data from 82,869 women who were age 27 to 44 years in 1991. The women, participants in the Nurses' Health Study II, reported the amount and type of alcohol they consumed on biennial questionnaires. They also reported whether they had received a diagnosis of psoriasis.
Through 2005, 1,150 cases of psoriasis developed, 1,069 of which were used for analysis. Compared with women who did not drink alcohol, the risk of psoriasis was 72 percent greater among women who had an average of 2.3 drinks per week or more. When beverages were assessed by type, there was an association between non-light beer drinking and psoriasis, such that women who drank five or more beers per week had a risk for the condition that was 1.8 times higher. Light beer, red wine, white wine and liquor were not associated with psoriasis risk.
When only confirmed psoriasis cases—those in which women provided more details about their condition on a seven-item self-assessment—were considered, the risk for psoriasis was 2.3 times higher for women who drank five or more beers per week than women who did not drink beer.
"Non-light beer was the only alcoholic beverage that increased the risk for psoriasis, suggesting that certain non-alcoholic components of beer, which are not found in wine or liquor, may play an important role in new-onset psoriasis," the authors write. "One of these components may be the starch source used in making beer. Beer is one of the few non-distilled alcoholic beverages that use a starch source for fermentation, which is commonly barley." Barley and other starches contain gluten, to which some individuals with psoriasis show a sensitivity. Lower amounts of grain are used to make light beer as compared with non-light beer, potentially explaining why light beer was not associated with psoriasis risk, they note.
"Women with a high risk of psoriasis may consider avoiding higher intake of non-light beer," the authors conclude. "We suggest conducting further investigations into the potential mechanisms of non-light beer inducing new-onset psoriasis."
Mediterranean diet = skin cancer prevention
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We all want that summer glow that comes from a day at the beach, but taking in the rays can have long-term implications for our health. Now Dr. Niva Shapira of Tel Aviv University's School of Health Professions suggests a way to make fun in the sun safer — and it's all in our food.
In a study recently published in Nutrition Reviews, Dr. Shapira has shown that a diet rich in antioxidants and omega-3 fatty acids, like the diet eaten in Mediterranean regions where melanoma rates are extremely low, can help protect us from skin cancer.
The sun's rays damage both the skin and the immune system by penetrating the skin and causing photo-oxidation, she explains, affecting both the cells themselves and the body's ability to repair any damage. Her prescription is to "go Greek" with foods such as olive oil, fish, yogurt and colorful fruits and vegetables to fight the oxidizing effect of the sun, as well as regular applications of sunscreen and appropriate body coverings such as hats, beach coverups, and other sportswear.
Drinking to your health
Dr. Niva Shapira
Previous research demonstrated that the sun's UV rays damage the skin by exciting its molecules and causing them to become oxidized, says Dr. Shapira. "My theory was that if you prepared the body with sufficient and relevant antioxidants, damage could be reduced."
For a study at the Baltic Sea, Dr. Shapira and Prof. Bodo Kuklinski of Rostock University organized two groups. One group was provided a drink high in antioxidants, while the other enjoyed beverages such as sodas. Those who hydrated with the antioxidant-rich drink had fifty percent fewer oxidation products (i.e. MDA) in their blood at the end of the two-week period, which included five to six hours of exposure to the sun daily. Further studies proved that these antioxidants, especially carotenoids — fruit and vegetable pigments like red from tomatoes and watermelons and orange from carrots and pumpkins that accumulate in the skin where they serve as a first line of protection — had delayed the phenomenon of skin erythema, which indicates the initiation of tissue and DNA damage that can lead to skin cancer.
This information is invaluable, especially in light of climate change, notes Dr. Shapira. As temperature and humidity get stronger, which aggravates the damaging effect of solar UV rays, it is increasingly difficult for sunscreen alone to protect effectively. So while covering up, slathering on the sunscreen, and avoiding the sun during peak hours are still important to prevent a burn, consider dietary changes too, to promote skin health.
Go fish with a glass of red … and other colors
It might be tempting to load up on dietary supplements instead of changing the diet, but according to Dr. Shapira, supplements are simply not as effective. Foods provide nutrient "synergy," she says. "In foods, many vitamins and various antioxidants and bioactive ingredients work to support one another and the body's natural protective mechanisms. Synergies between the nutrients in your food, which make a significant contribution to health, may contrast with the relative isolation of a vitamin supplement."
The research is getting attention: for the first time, the Israeli Cancer Association has included the nutritional information as part of their "Smart in the Sun" advisories.
It's not necessary to move to Greece, Israel or Turkey to get the benefit of the diet. Most of the appropriate foods are stocked in American grocery stores. Olive oil, fresh fish, fruits and vegetables, red wine in moderation, whole grains, beans and lots of water should be at the top of the shopping list, Dr. Shapira advises.
And there are some foods to avoid, she points out. Go light on red meat, processed foods, and alcohol (red wine is preferable), and be wary of foods that contain the photosensitizing compound psoralen, such as parsley, celery, dill, cilantro and figs.
We all want that summer glow that comes from a day at the beach, but taking in the rays can have long-term implications for our health. Now Dr. Niva Shapira of Tel Aviv University's School of Health Professions suggests a way to make fun in the sun safer — and it's all in our food.
In a study recently published in Nutrition Reviews, Dr. Shapira has shown that a diet rich in antioxidants and omega-3 fatty acids, like the diet eaten in Mediterranean regions where melanoma rates are extremely low, can help protect us from skin cancer.
The sun's rays damage both the skin and the immune system by penetrating the skin and causing photo-oxidation, she explains, affecting both the cells themselves and the body's ability to repair any damage. Her prescription is to "go Greek" with foods such as olive oil, fish, yogurt and colorful fruits and vegetables to fight the oxidizing effect of the sun, as well as regular applications of sunscreen and appropriate body coverings such as hats, beach coverups, and other sportswear.
Drinking to your health
Dr. Niva Shapira
Previous research demonstrated that the sun's UV rays damage the skin by exciting its molecules and causing them to become oxidized, says Dr. Shapira. "My theory was that if you prepared the body with sufficient and relevant antioxidants, damage could be reduced."
For a study at the Baltic Sea, Dr. Shapira and Prof. Bodo Kuklinski of Rostock University organized two groups. One group was provided a drink high in antioxidants, while the other enjoyed beverages such as sodas. Those who hydrated with the antioxidant-rich drink had fifty percent fewer oxidation products (i.e. MDA) in their blood at the end of the two-week period, which included five to six hours of exposure to the sun daily. Further studies proved that these antioxidants, especially carotenoids — fruit and vegetable pigments like red from tomatoes and watermelons and orange from carrots and pumpkins that accumulate in the skin where they serve as a first line of protection — had delayed the phenomenon of skin erythema, which indicates the initiation of tissue and DNA damage that can lead to skin cancer.
This information is invaluable, especially in light of climate change, notes Dr. Shapira. As temperature and humidity get stronger, which aggravates the damaging effect of solar UV rays, it is increasingly difficult for sunscreen alone to protect effectively. So while covering up, slathering on the sunscreen, and avoiding the sun during peak hours are still important to prevent a burn, consider dietary changes too, to promote skin health.
Go fish with a glass of red … and other colors
It might be tempting to load up on dietary supplements instead of changing the diet, but according to Dr. Shapira, supplements are simply not as effective. Foods provide nutrient "synergy," she says. "In foods, many vitamins and various antioxidants and bioactive ingredients work to support one another and the body's natural protective mechanisms. Synergies between the nutrients in your food, which make a significant contribution to health, may contrast with the relative isolation of a vitamin supplement."
The research is getting attention: for the first time, the Israeli Cancer Association has included the nutritional information as part of their "Smart in the Sun" advisories.
It's not necessary to move to Greece, Israel or Turkey to get the benefit of the diet. Most of the appropriate foods are stocked in American grocery stores. Olive oil, fresh fish, fruits and vegetables, red wine in moderation, whole grains, beans and lots of water should be at the top of the shopping list, Dr. Shapira advises.
And there are some foods to avoid, she points out. Go light on red meat, processed foods, and alcohol (red wine is preferable), and be wary of foods that contain the photosensitizing compound psoralen, such as parsley, celery, dill, cilantro and figs.
Caffeine Only Benefit Of Energy Drinks
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Popular energy drinks promise better athletic performance and weight loss, but do the claims hold up? Not always, say researchers at Nova Southeastern University in Florida.
"Energy drinks typically feature caffeine and a combination of other ingredients, including taurine, sucrose, guarana, ginseng, niacin, pyridoxine and cyanocobalamin," says Stephanie Ballard, PharmD., assistant professor of pharmacy practice at Nova Southeastern University's West Palm Beach campus.
"Most of the performance-enhancing effects of energy drinks can be linked to their caffeine content," she says. "Caffeine has been consistently been observed to enhance aerobic performance, although its effects on anaerobic performance may vary."
Ballard and colleagues Jennifer Wellborn-Kim, PharmD., and Kevin Clauson, PharmD., authored a paper, Effects of Commercial Energy Drink Consumption on Athletic Performance and Body Composition, in a recent issue of The Physician and Sportsmedicine.
"There is conflicting evidence of the impact of energy drinks on weight loss," Ballard adds, "although some data suggest that combining energy drink use with exercise may enhance body fat reduction. Increases in burning calories and losing weight are likely subject to diminishing returns as users become habituated to caffeine. "
Don't forget these drinks are often loaded with sugar, she adds. "Despite their use for weight loss, energy drinks may be contributing to the obesity epidemic alongside less caffeinated, sugary drinks like soda."
Red Bull-swilling athletes should be aware of the caffeine limitations of sports governing bodies, as well as the risks to their health.
"Although caffeine was removed from the World Anti-Doping Agency's prohibited list in 2004, it is still followed under the 2009 Monitoring Program to identify patterns of misuse," says Ballard. "For the National Collegiate Athletic Association, athletes are considered to be doping if urinary caffeine is greater than 15 µg/mL, which is about the same as drinking eight cups of coffee, each containing 100 mg of caffeine."
As with any active substance, energy drink ingredients may cause adverse effects, particularly with high episodic consumption, warns Ballard. And these drinks, which are classified as dietary supplements, are in a regulatory gray area, allowing them to sidestep the caffeine limitations assigned to foods and soft drinks.
"The FDA limits caffeine in soft drinks to 71 mg/12 fluid oz," says Ballard. "But energy drinks can contain as much as 505 mg of caffeine in a single container – the equivalent of drinking 14 cans of Coca-Cola. Caffeine has been reported to cause insomnia, nervousness, arrhythmias, osteoporosis, cardiovascular disease, pregnancy and childbirth complication, gastrointestinal upset and death."
But small amounts can be safe and still boost performance. "Caffeine in amounts of up to 6 mg/kg may produce benefits with low risk of adverse effects," says Ballard.
Popular energy drinks promise better athletic performance and weight loss, but do the claims hold up? Not always, say researchers at Nova Southeastern University in Florida.
"Energy drinks typically feature caffeine and a combination of other ingredients, including taurine, sucrose, guarana, ginseng, niacin, pyridoxine and cyanocobalamin," says Stephanie Ballard, PharmD., assistant professor of pharmacy practice at Nova Southeastern University's West Palm Beach campus.
"Most of the performance-enhancing effects of energy drinks can be linked to their caffeine content," she says. "Caffeine has been consistently been observed to enhance aerobic performance, although its effects on anaerobic performance may vary."
Ballard and colleagues Jennifer Wellborn-Kim, PharmD., and Kevin Clauson, PharmD., authored a paper, Effects of Commercial Energy Drink Consumption on Athletic Performance and Body Composition, in a recent issue of The Physician and Sportsmedicine.
"There is conflicting evidence of the impact of energy drinks on weight loss," Ballard adds, "although some data suggest that combining energy drink use with exercise may enhance body fat reduction. Increases in burning calories and losing weight are likely subject to diminishing returns as users become habituated to caffeine. "
Don't forget these drinks are often loaded with sugar, she adds. "Despite their use for weight loss, energy drinks may be contributing to the obesity epidemic alongside less caffeinated, sugary drinks like soda."
Red Bull-swilling athletes should be aware of the caffeine limitations of sports governing bodies, as well as the risks to their health.
"Although caffeine was removed from the World Anti-Doping Agency's prohibited list in 2004, it is still followed under the 2009 Monitoring Program to identify patterns of misuse," says Ballard. "For the National Collegiate Athletic Association, athletes are considered to be doping if urinary caffeine is greater than 15 µg/mL, which is about the same as drinking eight cups of coffee, each containing 100 mg of caffeine."
As with any active substance, energy drink ingredients may cause adverse effects, particularly with high episodic consumption, warns Ballard. And these drinks, which are classified as dietary supplements, are in a regulatory gray area, allowing them to sidestep the caffeine limitations assigned to foods and soft drinks.
"The FDA limits caffeine in soft drinks to 71 mg/12 fluid oz," says Ballard. "But energy drinks can contain as much as 505 mg of caffeine in a single container – the equivalent of drinking 14 cans of Coca-Cola. Caffeine has been reported to cause insomnia, nervousness, arrhythmias, osteoporosis, cardiovascular disease, pregnancy and childbirth complication, gastrointestinal upset and death."
But small amounts can be safe and still boost performance. "Caffeine in amounts of up to 6 mg/kg may produce benefits with low risk of adverse effects," says Ballard.
Lower levels of folate=symptoms of dementia and poor brain function, also called "cognitive decline"
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B vitamins–B-6, B-12 and folate–all nourish the brain. But much remains to be discovered about the relation between these essential nutrients and our brainpower.
U.S. Department of Agriculture (USDA) nutritionist Lindsay H. Allen has collaborated in ongoing research that has taken a closer look at the role these nutrients may play in preventing decline in brain function. The investigations, led by Mary N. Haan of the University of California-San Francisco, are part of the multiyear Sacramento (Calif.) Area Latino Study on Aging, or "SALSA." Begun in 1996, the study attracted nearly 1,800 Hispanic seniors, ages 60 to 101, as volunteers.
According to Allen, the research is needed because many studies of B vitamins and brain function have given inconsistent or conflicting results. Allen is director of the Agricultural Research Service (ARS) Western Human Nutrition Research Center in Davis, Calif. ARS is the chief intramural scientific research agency of USDA. Scientists from the University of California-Davis (UCD) and the UCD Medical Center also are collaborating in the research.
An analysis of volunteers' blood samples showed that lower levels of one B vitamin, folate, were associated with symptoms of dementia and poor brain function, also called "cognitive decline," as determined by standard tests of memory and other factors. The impairments were detectable even though less than 1 percent of the volunteers were actually deficient in folate.
In women, but not men, low levels of folate were associated with symptoms of depression. In fact, female volunteers whose plasma folate levels were in the lowest third were more than twice as likely to have symptoms of depression as volunteers in the highest third. That finding provided new evidence of an association between lower blood folate and depression. Depression is already known to affect brain function.
In research with vitamin B-12, the SALSA team determined that a protein known as holoTC, short for holotranscobalamin, might be key to a new approach for detecting cognitive decline earlier and more accurately.
B vitamins–B-6, B-12 and folate–all nourish the brain. But much remains to be discovered about the relation between these essential nutrients and our brainpower.
U.S. Department of Agriculture (USDA) nutritionist Lindsay H. Allen has collaborated in ongoing research that has taken a closer look at the role these nutrients may play in preventing decline in brain function. The investigations, led by Mary N. Haan of the University of California-San Francisco, are part of the multiyear Sacramento (Calif.) Area Latino Study on Aging, or "SALSA." Begun in 1996, the study attracted nearly 1,800 Hispanic seniors, ages 60 to 101, as volunteers.
According to Allen, the research is needed because many studies of B vitamins and brain function have given inconsistent or conflicting results. Allen is director of the Agricultural Research Service (ARS) Western Human Nutrition Research Center in Davis, Calif. ARS is the chief intramural scientific research agency of USDA. Scientists from the University of California-Davis (UCD) and the UCD Medical Center also are collaborating in the research.
An analysis of volunteers' blood samples showed that lower levels of one B vitamin, folate, were associated with symptoms of dementia and poor brain function, also called "cognitive decline," as determined by standard tests of memory and other factors. The impairments were detectable even though less than 1 percent of the volunteers were actually deficient in folate.
In women, but not men, low levels of folate were associated with symptoms of depression. In fact, female volunteers whose plasma folate levels were in the lowest third were more than twice as likely to have symptoms of depression as volunteers in the highest third. That finding provided new evidence of an association between lower blood folate and depression. Depression is already known to affect brain function.
In research with vitamin B-12, the SALSA team determined that a protein known as holoTC, short for holotranscobalamin, might be key to a new approach for detecting cognitive decline earlier and more accurately.
Moderate chocolate consumption linked to lower risks of heart failure
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Study highlights:
• Eating moderate amounts of chocolate is linked to lower risks of heart failure among middle-aged and older women, compared to eating no chocolate at all.
• Experts warn Americans that the potential for heart health benefits from chocolate must be carefully weighed against the negative risks including excess calories and fat.
• This is the first study to examine long-term effects of eating chocolate on heart failure rates.
Middle-aged and elderly Swedish women who regularly ate a small amount of chocolate had lower risks of heart failure risks, in a study reported in Circulation: Heart Failure, a journal of the American Heart Association.
The nine-year study, conducted among 31,823 middle-aged and elderly Swedish women, looked at the relationship of the amount of high-quality chocolate the women ate, compared to their risk for heart failure. The quality of chocolate consumed by the women had a higher density cocoa content somewhat like dark chocolate by American standards. In this study, researchers found:
Women who ate an average of one to two servings of the high-quality chocolate per week had a 32 percent lower risk of developing heart failure.
Those who had one to three servings per month had a 26 percent lower risk.
Those who consumed at least one serving daily or more didn’t appear to benefit from a protective effect against heart failure.
The lack of a protective effect among women eating chocolate every day is probably due to the additional calories gained from eating chocolate instead of more nutritious foods, said Murrray Mittleman, M.D., Dr.P.H., lead researcher of the study.
“You can’t ignore that chocolate is a relatively calorie-dense food and large amounts of habitual consumption is going to raise your risks for weight gain,” said Mittleman, director of the Cardiovascular Epidemiology Research Unit at Harvard Medical School’s Beth Israel Deaconess Medical Center in Boston. “But if you’re going to have a treat, dark chocolate is probably a good choice, as long as it’s in moderation.”
High concentration of compounds called “flavonoids” in chocolate may lower blood pressure, among other benefits, according to mostly short-term studies. However, this is the first study to show long-term outcomes related specifically to heart failure, which can result from ongoing untreated high blood pressure.
In the observational study, researchers analyzed self-reported food-frequency questionnaire responses from participants 48-to-83-years-old in the Swedish Mammography Cohort. Combining the results with data from national Swedish hospitalization and death registries between 1998 through 2006, the researchers used multiple forms of statistical modeling to reach their conclusions on heart failure and chocolate consumption.
Mittleman said differences in chocolate quality affect the study’s implications for Americans. Higher cocoa content is associated with greater heart benefits. In Sweden, even milk chocolate has a higher cocoa concentration than dark chocolate sold in the United States.
Although 90 percent of all chocolate eaten across Sweden during the study period was milk chocolate, it contained about 30 percent cocoa solids. U.S. standards only require 15 percent cocoa solids to qualify as dark chocolate. So, by comparison, American chocolate may have fewer heart benefits and more calories and fat per equivalent amounts of cocoa content compared to the chocolate eaten by the Swedish women in the study.
Also, the average serving size for Swedish women in the study ranged from 19 grams among those 62 and older, to 30 grams among those 61 and younger. In contrast, the standard American portion size is 20 grams.
“Those tempted to use these data as their rationale for eating large amounts of chocolate or engaging in more frequent chocolate consumption are not interpreting this study appropriately,” said Linda Van Horn, Ph.D., R.D., immediate past chair of the American Heart Association Nutrition Committee and professor in the Department of Preventive Medicine at Northwestern University’s Feinberg School of Medicine in Chicago. “This is not an ‘eat all you want’ take-home message, rather it’s that eating a little dark chocolate can be healthful, as long as other adverse behaviors do not occur, such as weight gain or excessive intake of non-nutrient dense ‘empty’ calories.”
Heart failure occurs among about 1 percent of Americans over age 65. A condition in which the heart can’t pump enough blood to the rest of the body, heart failure rates are increasing as our aging population grows.
“Anything that helps to decrease heart failure is an important issue worth examining,” Mittleman said.
Study highlights:
• Eating moderate amounts of chocolate is linked to lower risks of heart failure among middle-aged and older women, compared to eating no chocolate at all.
• Experts warn Americans that the potential for heart health benefits from chocolate must be carefully weighed against the negative risks including excess calories and fat.
• This is the first study to examine long-term effects of eating chocolate on heart failure rates.
Middle-aged and elderly Swedish women who regularly ate a small amount of chocolate had lower risks of heart failure risks, in a study reported in Circulation: Heart Failure, a journal of the American Heart Association.
The nine-year study, conducted among 31,823 middle-aged and elderly Swedish women, looked at the relationship of the amount of high-quality chocolate the women ate, compared to their risk for heart failure. The quality of chocolate consumed by the women had a higher density cocoa content somewhat like dark chocolate by American standards. In this study, researchers found:
Women who ate an average of one to two servings of the high-quality chocolate per week had a 32 percent lower risk of developing heart failure.
Those who had one to three servings per month had a 26 percent lower risk.
Those who consumed at least one serving daily or more didn’t appear to benefit from a protective effect against heart failure.
The lack of a protective effect among women eating chocolate every day is probably due to the additional calories gained from eating chocolate instead of more nutritious foods, said Murrray Mittleman, M.D., Dr.P.H., lead researcher of the study.
“You can’t ignore that chocolate is a relatively calorie-dense food and large amounts of habitual consumption is going to raise your risks for weight gain,” said Mittleman, director of the Cardiovascular Epidemiology Research Unit at Harvard Medical School’s Beth Israel Deaconess Medical Center in Boston. “But if you’re going to have a treat, dark chocolate is probably a good choice, as long as it’s in moderation.”
High concentration of compounds called “flavonoids” in chocolate may lower blood pressure, among other benefits, according to mostly short-term studies. However, this is the first study to show long-term outcomes related specifically to heart failure, which can result from ongoing untreated high blood pressure.
In the observational study, researchers analyzed self-reported food-frequency questionnaire responses from participants 48-to-83-years-old in the Swedish Mammography Cohort. Combining the results with data from national Swedish hospitalization and death registries between 1998 through 2006, the researchers used multiple forms of statistical modeling to reach their conclusions on heart failure and chocolate consumption.
Mittleman said differences in chocolate quality affect the study’s implications for Americans. Higher cocoa content is associated with greater heart benefits. In Sweden, even milk chocolate has a higher cocoa concentration than dark chocolate sold in the United States.
Although 90 percent of all chocolate eaten across Sweden during the study period was milk chocolate, it contained about 30 percent cocoa solids. U.S. standards only require 15 percent cocoa solids to qualify as dark chocolate. So, by comparison, American chocolate may have fewer heart benefits and more calories and fat per equivalent amounts of cocoa content compared to the chocolate eaten by the Swedish women in the study.
Also, the average serving size for Swedish women in the study ranged from 19 grams among those 62 and older, to 30 grams among those 61 and younger. In contrast, the standard American portion size is 20 grams.
“Those tempted to use these data as their rationale for eating large amounts of chocolate or engaging in more frequent chocolate consumption are not interpreting this study appropriately,” said Linda Van Horn, Ph.D., R.D., immediate past chair of the American Heart Association Nutrition Committee and professor in the Department of Preventive Medicine at Northwestern University’s Feinberg School of Medicine in Chicago. “This is not an ‘eat all you want’ take-home message, rather it’s that eating a little dark chocolate can be healthful, as long as other adverse behaviors do not occur, such as weight gain or excessive intake of non-nutrient dense ‘empty’ calories.”
Heart failure occurs among about 1 percent of Americans over age 65. A condition in which the heart can’t pump enough blood to the rest of the body, heart failure rates are increasing as our aging population grows.
“Anything that helps to decrease heart failure is an important issue worth examining,” Mittleman said.
Moderate drinking, especially wine, associated with better cognitive function
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A large prospective study of 5033 men and women in the Tromsø Study in northern Norway has reported that moderate wine consumption is independently associated with better performance on cognitive tests. The subjects (average age 58 and free of stroke) were followed over 7 years during which they were tested with a range of cognitive function tests. Among women, there was a lower risk of a poor testing score for those who consumed wine at least 4 or more times over two weeks in comparison with those who drink < 1 time during this period The expected associations between other risk factors for poor cognitive functioning were seen, i.e. lower testing scores among people who were older, less educated, smokers, and those with depression, diabetes, or hypertension.
It has long been known that "moderate people do moderate things." The authors state the same thing: "A positive effect of wine . . . could also be due to confounders such as socio-economic status and more favourable dietary and other lifestyle habits.
The authors also reported that not drinking was associated with significantly lower cognitive performance in women. As noted by the authors, in any observational study there is the possibility of other lifestyle habits affecting cognitive function, and the present study was not able to adjust for certain ones (such as diet, income, or profession) but did adjust for age, education, weight, depression, and cardiovascular disease as its major risk factors.
The results of this study support findings from previous research on the topic: In the last three decades, the association between moderate alcohol intake and cognitive function has been investigated in 68 studies comprising 145,308 men and women from various populations with various drinking patterns. Most studies show an association between light to moderate alcohol consumption and better cognitive function and reduced risk of dementia, including both vascular dementia and Alzheimer's Disease.
Such effects could relate to the presence in wine of a number of polyphenols (antioxidants) and other micro elements that may help reduce the risk of cognitive decline with ageing. Mechanisms that have been suggested for alcohol itself being protective against cognitive decline include effects on atherosclerosis ( hardening of the arteries), coagulation ( thickening of the blood and clotting), and reducing inflammation ( of artery walls, improving blood flow).
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A large prospective study of 5033 men and women in the Tromsø Study in northern Norway has reported that moderate wine consumption is independently associated with better performance on cognitive tests. The subjects (average age 58 and free of stroke) were followed over 7 years during which they were tested with a range of cognitive function tests. Among women, there was a lower risk of a poor testing score for those who consumed wine at least 4 or more times over two weeks in comparison with those who drink < 1 time during this period The expected associations between other risk factors for poor cognitive functioning were seen, i.e. lower testing scores among people who were older, less educated, smokers, and those with depression, diabetes, or hypertension.
It has long been known that "moderate people do moderate things." The authors state the same thing: "A positive effect of wine . . . could also be due to confounders such as socio-economic status and more favourable dietary and other lifestyle habits.
The authors also reported that not drinking was associated with significantly lower cognitive performance in women. As noted by the authors, in any observational study there is the possibility of other lifestyle habits affecting cognitive function, and the present study was not able to adjust for certain ones (such as diet, income, or profession) but did adjust for age, education, weight, depression, and cardiovascular disease as its major risk factors.
The results of this study support findings from previous research on the topic: In the last three decades, the association between moderate alcohol intake and cognitive function has been investigated in 68 studies comprising 145,308 men and women from various populations with various drinking patterns. Most studies show an association between light to moderate alcohol consumption and better cognitive function and reduced risk of dementia, including both vascular dementia and Alzheimer's Disease.
Such effects could relate to the presence in wine of a number of polyphenols (antioxidants) and other micro elements that may help reduce the risk of cognitive decline with ageing. Mechanisms that have been suggested for alcohol itself being protective against cognitive decline include effects on atherosclerosis ( hardening of the arteries), coagulation ( thickening of the blood and clotting), and reducing inflammation ( of artery walls, improving blood flow).
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Green leafy vegetables reduce diabetes risk
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Eating more green leafy vegetables can significantly reduce the risk of developing type 2 diabetes, finds research published today on bmj.com.
The authors, led by Patrice Carter at the University of Leicester, say there is a need for further investigation into the potential benefits of green leafy vegetables.
In the last two decades there has been a dramatic increase in the number of individuals developing type 2 diabetes worldwide.
Diets high in fruit and vegetables are known to help reduce both cancer and heart disease, but the relationship between fruit and vegetable intake and diabetes remains unclear, say the authors.
The researchers also note that previous research found that in 2002, 86% of UK adults consumed less than the recommended five portions of fruit and vegetables per day, with 62% consuming less than three portions. The study says that "it was estimated that inadequate consumption of fruit and vegetables could have accounted for 2.6 million deaths worldwide in the year 2000."
Patrice Carter and colleagues reviewed six studies involving over 220,000 participants that focused on the links between fruit and vegetable consumption and type 2 diabetes.
The results reveal that eating one and a half extra servings of green leafy vegetables a day reduces the risk of type 2 diabetes by 14%. However, eating more fruit and vegetables combined does not significantly affect this risk. Only a small number of studies were included in the meta-analysis and the benefit of fruit and vegetables as a whole for prevention of type 2 diabetes may have been obscured.
The authors believe that fruit and vegetables can prevent chronic diseases because of their antioxidant content. Green leafy vegetables such as spinach may also act to reduce type 2 diabetes risk due to their high magnesium content.
The authors argue that "our results support the evidence that 'foods' rather than isolated components such as antioxidants are beneficial for health … results from several supplement trials have produced disappointing results for prevention of disease."
In conclusion, they believe that offering tailored advice to encourage individuals to eat more green leafy vegetables should be investigated further.
In an accompanying editorial, Professor Jim Mann from the University of Otago in New Zealand, and Research Assistant Dagfinn Aune from Imperial College London, are cautious about the results and say the message of increasing overall fruit and vegetable intake must not be lost "in a plethora of magic bullets," even though green leafy vegetables clearly can be included as one of the five portions of fruit and vegetables per day.
They argue that given the limited number of studies, "it may be too early to dismiss a small reduction in risk for overall fruit and vegetable intake or other specific types of fruits and vegetables and too early for a conclusion regarding green leafy vegetables.
Eating more green leafy vegetables can significantly reduce the risk of developing type 2 diabetes, finds research published today on bmj.com.
The authors, led by Patrice Carter at the University of Leicester, say there is a need for further investigation into the potential benefits of green leafy vegetables.
In the last two decades there has been a dramatic increase in the number of individuals developing type 2 diabetes worldwide.
Diets high in fruit and vegetables are known to help reduce both cancer and heart disease, but the relationship between fruit and vegetable intake and diabetes remains unclear, say the authors.
The researchers also note that previous research found that in 2002, 86% of UK adults consumed less than the recommended five portions of fruit and vegetables per day, with 62% consuming less than three portions. The study says that "it was estimated that inadequate consumption of fruit and vegetables could have accounted for 2.6 million deaths worldwide in the year 2000."
Patrice Carter and colleagues reviewed six studies involving over 220,000 participants that focused on the links between fruit and vegetable consumption and type 2 diabetes.
The results reveal that eating one and a half extra servings of green leafy vegetables a day reduces the risk of type 2 diabetes by 14%. However, eating more fruit and vegetables combined does not significantly affect this risk. Only a small number of studies were included in the meta-analysis and the benefit of fruit and vegetables as a whole for prevention of type 2 diabetes may have been obscured.
The authors believe that fruit and vegetables can prevent chronic diseases because of their antioxidant content. Green leafy vegetables such as spinach may also act to reduce type 2 diabetes risk due to their high magnesium content.
The authors argue that "our results support the evidence that 'foods' rather than isolated components such as antioxidants are beneficial for health … results from several supplement trials have produced disappointing results for prevention of disease."
In conclusion, they believe that offering tailored advice to encourage individuals to eat more green leafy vegetables should be investigated further.
In an accompanying editorial, Professor Jim Mann from the University of Otago in New Zealand, and Research Assistant Dagfinn Aune from Imperial College London, are cautious about the results and say the message of increasing overall fruit and vegetable intake must not be lost "in a plethora of magic bullets," even though green leafy vegetables clearly can be included as one of the five portions of fruit and vegetables per day.
They argue that given the limited number of studies, "it may be too early to dismiss a small reduction in risk for overall fruit and vegetable intake or other specific types of fruits and vegetables and too early for a conclusion regarding green leafy vegetables.
Tuesday, August 17, 2010
Green Tea Extract Appears to Keep Cancer in Check in Majority of CLL Patients
Ω
Mayo Clinic has conducted the first clinical studies of tea extract in cancer patients
An extract of green tea appears to have clinical activity with low toxicity in chronic lymphocytic leukemia (CLL) patients who used it in a phase II clinical trial, say researchers at Mayo Clinic.
The findings are the latest in a series of Mayo studies to show promise for use of the chemical epigallocatechin gallate (EGCG) — the major component of green tea — in reducing the number of leukemia cells in patients with CLL. Mayo first tested EGCG in a variety of laboratory assays about eight years ago, and it was found to reduce the survival of CLL leukemic cells. This laboratory finding was followed by a successful phase I clinical trial — the first time green tea extract had been studied in CLL patients.
"Although only a comparative phase III trial can determine whether EGCG can delay progression of CLL, the benefits we have seen in most CLL patients who use the chemical suggest that it has modest clinical activity and may be useful for stabilizing this form of leukemia, potentially slowing it down," says Tait Shanafelt, M.D., a Mayo Clinic hematologist and lead author of the study.
"These studies advance the notion that a nutraceutical like EGCG can and should be studied as cancer preventives," says Neil Kay, M.D., a hematology researcher whose laboratory first tested the green tea extract in leukemic blood cells from CLL patients. "Using nontoxic chemicals to push back cancer growth to delay the need for toxic therapies is a worthy goal in oncology research — particularly for forms of cancer initially managed by observation such as CLL."
Drs. Shanafelt and Kay caution that EGCG is not a substitute for chemotherapy. All of the patients Mayo tested with EGCG were early stage, asymptomatic CLL patients who would not otherwise be treated until their disease progressed. The extract was supplied by the National Cancer Institute (NCI) and Polyphenon E International for these initial clinical trials.
CLL is a blood cancer that is a hybrid between leukemia and lymphoma. Progression of the disease is measured by the quantity of leukemia cells in the blood and bone marrow as well as enlargement of lymph nodes due to infiltration by the leukemia cells. In the phase I study, published in May 2009 in the Journal of Clinical Oncology, researchers found that the blood lymphocyte (leukemia cell) count was reduced in one-third of participants, and that the majority of patients who entered the study with enlarged lymph nodes due to involvement by CLL saw a 50 percent or greater reduction in their lymph node size.
Using the highest dose tested in the phase I study, the researchers launched their phase II clinical trial in an additional 36 patients. The results presented at the ASCO meeting evaluate the effects in these 36 patients as well as the six patients from the phase I trial treated at the same dose (total 42 patients). Results from 41 patients who have completed the study show that 31 percent of patients had a 20 percent or greater sustained reduction in blood leukemia count, and 69 percent of patients with enlarged lymph nodes saw a reduction of node size of 50 percent or greater.
In all, 69 percent of CLL patients had a biological response to EGCG as evidenced by a 20 percent or greater sustained reduction in blood lymphocyte count and/or a 50 percent or greater reduction in lymph node size, the researchers say.
Because EGCG was being studied in patients who did not otherwise need treatment, the researchers took a rigorous approach toward studying side effects. Most clinical trials of therapeutic agents only report grade 3 and higher side effects, but the researchers looked at and reported grade 1 and grade 2 as well. While a number of patients had transient grade 1 or 2 side effects, only three of 42 experienced a grade 3 side effect during their six months of treatment.
"All in all, the treatment was well tolerated with very mild side effects in most patients," Dr. Shanafelt says.
The researchers say that the prior publications on the effects of EGCG on CLL leukemia cells in the laboratory and the data from the published phase I study have been widely disseminated via the Internet by patient advocacy groups. Based on information from patients and colleagues throughout the country, the Mayo researchers have become aware that many CLL patients nationwide have started to use EGCG supplements, which are readily available over the counter.
"Without a phase III clinical trial, we cannot make a recommendation that EGCG be used by CLL patients, but those who want to take supplements should consult with their oncologists and need to receive appropriate monitoring using laboratory tests," Dr. Kay says.
The study was funded by grants from the NCI, the Mayo Comprehensive Cancer Center, and from donors and patient advocacy foundations. The authors declare no conflicts of interest.
Mayo Clinic has conducted the first clinical studies of tea extract in cancer patients
An extract of green tea appears to have clinical activity with low toxicity in chronic lymphocytic leukemia (CLL) patients who used it in a phase II clinical trial, say researchers at Mayo Clinic.
The findings are the latest in a series of Mayo studies to show promise for use of the chemical epigallocatechin gallate (EGCG) — the major component of green tea — in reducing the number of leukemia cells in patients with CLL. Mayo first tested EGCG in a variety of laboratory assays about eight years ago, and it was found to reduce the survival of CLL leukemic cells. This laboratory finding was followed by a successful phase I clinical trial — the first time green tea extract had been studied in CLL patients.
"Although only a comparative phase III trial can determine whether EGCG can delay progression of CLL, the benefits we have seen in most CLL patients who use the chemical suggest that it has modest clinical activity and may be useful for stabilizing this form of leukemia, potentially slowing it down," says Tait Shanafelt, M.D., a Mayo Clinic hematologist and lead author of the study.
"These studies advance the notion that a nutraceutical like EGCG can and should be studied as cancer preventives," says Neil Kay, M.D., a hematology researcher whose laboratory first tested the green tea extract in leukemic blood cells from CLL patients. "Using nontoxic chemicals to push back cancer growth to delay the need for toxic therapies is a worthy goal in oncology research — particularly for forms of cancer initially managed by observation such as CLL."
Drs. Shanafelt and Kay caution that EGCG is not a substitute for chemotherapy. All of the patients Mayo tested with EGCG were early stage, asymptomatic CLL patients who would not otherwise be treated until their disease progressed. The extract was supplied by the National Cancer Institute (NCI) and Polyphenon E International for these initial clinical trials.
CLL is a blood cancer that is a hybrid between leukemia and lymphoma. Progression of the disease is measured by the quantity of leukemia cells in the blood and bone marrow as well as enlargement of lymph nodes due to infiltration by the leukemia cells. In the phase I study, published in May 2009 in the Journal of Clinical Oncology, researchers found that the blood lymphocyte (leukemia cell) count was reduced in one-third of participants, and that the majority of patients who entered the study with enlarged lymph nodes due to involvement by CLL saw a 50 percent or greater reduction in their lymph node size.
Using the highest dose tested in the phase I study, the researchers launched their phase II clinical trial in an additional 36 patients. The results presented at the ASCO meeting evaluate the effects in these 36 patients as well as the six patients from the phase I trial treated at the same dose (total 42 patients). Results from 41 patients who have completed the study show that 31 percent of patients had a 20 percent or greater sustained reduction in blood leukemia count, and 69 percent of patients with enlarged lymph nodes saw a reduction of node size of 50 percent or greater.
In all, 69 percent of CLL patients had a biological response to EGCG as evidenced by a 20 percent or greater sustained reduction in blood lymphocyte count and/or a 50 percent or greater reduction in lymph node size, the researchers say.
Because EGCG was being studied in patients who did not otherwise need treatment, the researchers took a rigorous approach toward studying side effects. Most clinical trials of therapeutic agents only report grade 3 and higher side effects, but the researchers looked at and reported grade 1 and grade 2 as well. While a number of patients had transient grade 1 or 2 side effects, only three of 42 experienced a grade 3 side effect during their six months of treatment.
"All in all, the treatment was well tolerated with very mild side effects in most patients," Dr. Shanafelt says.
The researchers say that the prior publications on the effects of EGCG on CLL leukemia cells in the laboratory and the data from the published phase I study have been widely disseminated via the Internet by patient advocacy groups. Based on information from patients and colleagues throughout the country, the Mayo researchers have become aware that many CLL patients nationwide have started to use EGCG supplements, which are readily available over the counter.
"Without a phase III clinical trial, we cannot make a recommendation that EGCG be used by CLL patients, but those who want to take supplements should consult with their oncologists and need to receive appropriate monitoring using laboratory tests," Dr. Kay says.
The study was funded by grants from the NCI, the Mayo Comprehensive Cancer Center, and from donors and patient advocacy foundations. The authors declare no conflicts of interest.
Saturday, August 14, 2010
Acetaminophen use in adolescents linked to doubled risk of asthma
Ω
New evidence linking the use of acetaminophen (Tylenol) to development of asthma and eczema suggests that even monthly use of the drug in adolescents may more than double risk of asthma in adolescents compared to those who used none at all; yearly use was associated with a 50 percent increase in the risk of asthma.
The research results will be published online on the American Thoracic Society's Web site ahead of the print edition of the American Journal of Respiratory and Critical Care Medicine.
"This study has identified that the reported use of acetaminophen in 13- and 14 year old adolescent children was associated with an exposure-dependent increased risk of asthma symptoms," said study first author Richard Beasley, M.D., professor of medicine, at the Medical Research Institute of New Zealand on behalf of the International Study of Asthma and Allergies in Childhood (ISAAC).
As part of the ISAAC program, two written questionnaires and one video questionnaire were administered to more than 300,000 13- and 14 year old children in 113 centers throughout 50 countries, asking them to quantify their use of acetaminophen (none, "medium"— at least once in the last year, or "high"— at least once in the last month) and their asthma, eczema and allergy symptoms.
There was a significant association between acetaminophen use and risk of asthma and eczema. For medium users the risk of asthma 43 percent higher than non-users; high users had 2.51 times the risk of non-users. Similarly, the risk of rhinoconjunctivitis (allergic nasal congestion) was 38 percent higher for medium users and 2.39 times as great for high users compared to non-users. For eczema, the relative risks were 31 percent and 99 percent respectively.
As this was a cross-sectional study, causality could not be determined. However, there is mounting evidence that suggests a causal link.
A longitudinal study on a small population in Ethiopia that examined the risk of asthma and allergies associated with acetaminophen use elucidated a temporal relationship between acetaminophen usage and the development of asthma and allergy symptoms, lending greater evidence to the possibility that acetaminophen usage may indeed cause the increased risk. This study will also be published online in advance of publication of the American Journal of Respiratory and Critical Care Medicine.
Moreover, in an earlier study from the United States, 13 and 14-year-old children with asthma were randomized to take either acetaminophen or ibuprofen after a febrile illness. For those whose illness was respiratory, there was an increased risk of a subsequent outpatient visit for asthma.
There are a number of biologically plausible explanations for how acetaminophen might increase risk of asthma and allergy. Acetaminophen may have a systemic inflammatory effect, possibly increasing oxygen stress resulting from the depletion of glutathione-dependent enzymes, which may in turn lead to enhanced TH2 allergic immune responses. Furthermore, acetaminophen may suppress the immune response to, and prolong the symptomatic illness from, rhinovirus infections, which are a common cause of severe asthma exacerbations in childhood.
Given the increased risk associated with acetaminophen usage, Dr. Beasley and colleagues calculated that the population attributable risks—the percentage of cases that might be avoided if the risk factor were to be eliminated—were indicative of a remarkable impact from acetaminophen usage.
"The overall population attributable risks for current symptoms of severe asthma were around 40 percent, suggesting that if the associations were causal, they would be of major public health significance," said Dr. Beasley. "Randomized controlled trials are now urgently required to investigate this relationship further and to guide the use of antipyretics, not only in children but in pregnancy and adult life."
New evidence linking the use of acetaminophen (Tylenol) to development of asthma and eczema suggests that even monthly use of the drug in adolescents may more than double risk of asthma in adolescents compared to those who used none at all; yearly use was associated with a 50 percent increase in the risk of asthma.
The research results will be published online on the American Thoracic Society's Web site ahead of the print edition of the American Journal of Respiratory and Critical Care Medicine.
"This study has identified that the reported use of acetaminophen in 13- and 14 year old adolescent children was associated with an exposure-dependent increased risk of asthma symptoms," said study first author Richard Beasley, M.D., professor of medicine, at the Medical Research Institute of New Zealand on behalf of the International Study of Asthma and Allergies in Childhood (ISAAC).
As part of the ISAAC program, two written questionnaires and one video questionnaire were administered to more than 300,000 13- and 14 year old children in 113 centers throughout 50 countries, asking them to quantify their use of acetaminophen (none, "medium"— at least once in the last year, or "high"— at least once in the last month) and their asthma, eczema and allergy symptoms.
There was a significant association between acetaminophen use and risk of asthma and eczema. For medium users the risk of asthma 43 percent higher than non-users; high users had 2.51 times the risk of non-users. Similarly, the risk of rhinoconjunctivitis (allergic nasal congestion) was 38 percent higher for medium users and 2.39 times as great for high users compared to non-users. For eczema, the relative risks were 31 percent and 99 percent respectively.
As this was a cross-sectional study, causality could not be determined. However, there is mounting evidence that suggests a causal link.
A longitudinal study on a small population in Ethiopia that examined the risk of asthma and allergies associated with acetaminophen use elucidated a temporal relationship between acetaminophen usage and the development of asthma and allergy symptoms, lending greater evidence to the possibility that acetaminophen usage may indeed cause the increased risk. This study will also be published online in advance of publication of the American Journal of Respiratory and Critical Care Medicine.
Moreover, in an earlier study from the United States, 13 and 14-year-old children with asthma were randomized to take either acetaminophen or ibuprofen after a febrile illness. For those whose illness was respiratory, there was an increased risk of a subsequent outpatient visit for asthma.
There are a number of biologically plausible explanations for how acetaminophen might increase risk of asthma and allergy. Acetaminophen may have a systemic inflammatory effect, possibly increasing oxygen stress resulting from the depletion of glutathione-dependent enzymes, which may in turn lead to enhanced TH2 allergic immune responses. Furthermore, acetaminophen may suppress the immune response to, and prolong the symptomatic illness from, rhinovirus infections, which are a common cause of severe asthma exacerbations in childhood.
Given the increased risk associated with acetaminophen usage, Dr. Beasley and colleagues calculated that the population attributable risks—the percentage of cases that might be avoided if the risk factor were to be eliminated—were indicative of a remarkable impact from acetaminophen usage.
"The overall population attributable risks for current symptoms of severe asthma were around 40 percent, suggesting that if the associations were causal, they would be of major public health significance," said Dr. Beasley. "Randomized controlled trials are now urgently required to investigate this relationship further and to guide the use of antipyretics, not only in children but in pregnancy and adult life."
Thursday, August 12, 2010
Free statins with fast food could neutralize heart risk, scientists say
Ω
Fast food outlets could provide statin drugs free of charge so that customers can neutralize the heart disease dangers of fatty food, researchers at Imperial College London suggest in a new study published this week
Fast food outlets could provide statin drugs free of charge so that customers can neutralise the heart disease dangers of fatty food, researchers at Imperial College London suggest in a new study published this week.
Statins reduce the amount of unhealthy "LDL" cholesterol in the blood. A wealth of trial data has proven them to be highly effective at lowering a person's heart attack risk.
In a paper published in the Sunday 15 August issue of the American Journal of Cardiology, Dr Darrel Francis and colleagues calculate that the reduction in cardiovascular risk offered by a statin is enough to offset the increase in heart attack risk from eating a cheeseburger and a milkshake.
Dr Francis, from the National Heart and Lung Institute at Imperial College London, who is the senior author of the study, said: "Statins don't cut out all of the unhealthy effects of burgers and fries. It's better to avoid fatty food altogether. But we've worked out that in terms of your likelihood of having a heart attack, taking a statin can reduce your risk to more or less the same degree as a fast food meal increases it."
One statin, simvastatin, is already available in Great Britain in low doses (10mg) over the counter at pharmacies without a prescription. Other statins are so far only prescribed by doctors, and limited by cost to patients at particular risk of heart attack or stroke. However, the cost of the tablets has fallen sharply in recent years (from ~£40/month to ~£1.50/month), such that the cost to the NHS of seeing a doctor is much greater than the cost of the tablet.
"It's ironic that people are free to take as many unhealthy condiments in fast food outlets as they like, but statins, which are beneficial to heart health, have to be prescribed," Dr Francis said.
Statins have among the best safety profiles of any medication. A very small proportion of regular statin users experience significant side effects, with problems in the liver and kidneys reported in between 1 in 1,000 and 1 in 10,000 people.
"Everybody knows that fast food is bad for you, but people continue to eat it because it tastes good. We're genetically programmed to prefer high-calorie foods, and sadly fast food chains will continue to sell unhealthy foods because it earns them a living.
"It makes sense to make risk-reducing supplements available just as easily as the unhealthy condiments that are provided free of charge. It would cost less than 5p per customer – not much different to a sachet of ketchup.
"When people engage in risky behaviours like driving or smoking, they're encouraged to take measures that minimise their risk, like wearing a seatbelt or choosing cigarettes with filters. Taking a statin is a rational way of lowering some of the risks of eating a fatty meal."
Studies have shown a clear link between total fat intake and blood cholesterol, which is strongly linked to heart disease. Recent evidence suggests that trans fats, which are found in high levels in fast food, are the component of the Western diet that is most dangerous in terms of heart disease risk.
Dr Francis and his colleagues used data from a previous large cohort study to quantify how a person's heart attack risk increases with their daily intake of total fat and trans fat. He compared this with the decrease in risk from various statins, based on a meta-analysis of seven randomised controlled trials.
The results showed that most statin regimes are able to compensate for the relative risk increase from eating a cheeseburger and a small milkshake.
The researchers note that studies should be conducted to assess the potential risks of allowing people to take statins freely, without medical supervision. They suggest that a warning on the packet should emphasise that no tablet can substitute for a healthy diet, and advise people to consult their doctor for more advice.
Ω
Fast food outlets could provide statin drugs free of charge so that customers can neutralize the heart disease dangers of fatty food, researchers at Imperial College London suggest in a new study published this week
Fast food outlets could provide statin drugs free of charge so that customers can neutralise the heart disease dangers of fatty food, researchers at Imperial College London suggest in a new study published this week.
Statins reduce the amount of unhealthy "LDL" cholesterol in the blood. A wealth of trial data has proven them to be highly effective at lowering a person's heart attack risk.
In a paper published in the Sunday 15 August issue of the American Journal of Cardiology, Dr Darrel Francis and colleagues calculate that the reduction in cardiovascular risk offered by a statin is enough to offset the increase in heart attack risk from eating a cheeseburger and a milkshake.
Dr Francis, from the National Heart and Lung Institute at Imperial College London, who is the senior author of the study, said: "Statins don't cut out all of the unhealthy effects of burgers and fries. It's better to avoid fatty food altogether. But we've worked out that in terms of your likelihood of having a heart attack, taking a statin can reduce your risk to more or less the same degree as a fast food meal increases it."
One statin, simvastatin, is already available in Great Britain in low doses (10mg) over the counter at pharmacies without a prescription. Other statins are so far only prescribed by doctors, and limited by cost to patients at particular risk of heart attack or stroke. However, the cost of the tablets has fallen sharply in recent years (from ~£40/month to ~£1.50/month), such that the cost to the NHS of seeing a doctor is much greater than the cost of the tablet.
"It's ironic that people are free to take as many unhealthy condiments in fast food outlets as they like, but statins, which are beneficial to heart health, have to be prescribed," Dr Francis said.
Statins have among the best safety profiles of any medication. A very small proportion of regular statin users experience significant side effects, with problems in the liver and kidneys reported in between 1 in 1,000 and 1 in 10,000 people.
"Everybody knows that fast food is bad for you, but people continue to eat it because it tastes good. We're genetically programmed to prefer high-calorie foods, and sadly fast food chains will continue to sell unhealthy foods because it earns them a living.
"It makes sense to make risk-reducing supplements available just as easily as the unhealthy condiments that are provided free of charge. It would cost less than 5p per customer – not much different to a sachet of ketchup.
"When people engage in risky behaviours like driving or smoking, they're encouraged to take measures that minimise their risk, like wearing a seatbelt or choosing cigarettes with filters. Taking a statin is a rational way of lowering some of the risks of eating a fatty meal."
Studies have shown a clear link between total fat intake and blood cholesterol, which is strongly linked to heart disease. Recent evidence suggests that trans fats, which are found in high levels in fast food, are the component of the Western diet that is most dangerous in terms of heart disease risk.
Dr Francis and his colleagues used data from a previous large cohort study to quantify how a person's heart attack risk increases with their daily intake of total fat and trans fat. He compared this with the decrease in risk from various statins, based on a meta-analysis of seven randomised controlled trials.
The results showed that most statin regimes are able to compensate for the relative risk increase from eating a cheeseburger and a small milkshake.
The researchers note that studies should be conducted to assess the potential risks of allowing people to take statins freely, without medical supervision. They suggest that a warning on the packet should emphasise that no tablet can substitute for a healthy diet, and advise people to consult their doctor for more advice.
Ω
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