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In four different studies presented at the American College of Gastroenterology's (ACG) 76th Annual Scientific meeting in Washington, DC, researchers explored the effectiveness of probiotics for antibiotic-associated diarrhea; as an anti-inflammatory agent for patients with ulcerative colitis, psoriasis and chronic fatigue syndrome; and for people with abdominal discomfort and bloating who have not been diagnosed with a functional bowel disorder, such as irritable bowel syndrome (IBS).
These four studies will be featured during an ACG press briefing on Tuesday, November 1, 2011 entitled: "Good, Bad and Ugly Bugs: Mother Nature as a Treatment for Better Health in the GI Tract," which will highlight new clinical science that explores the role of the "gut microbiota" –the bacterial composition of the GI tract – and the efficacy of probiotics and fecal microbiota transplantation in treating various GI conditions.
Probiotics are considered "good bacteria" that help maintain the natural balance of microflora in the digestive tract where trillions of bacteria live. While most of the more than 400 different species in the gut are healthy bacteria, others, "bad bugs" have the potential to cause damage to the digestive system. At times, an imbalance between the good and bad bacteria can lead to uncomfortable symptoms or illnesses. Probiotics are bacteria, or even sometimes yeast, which may alleviate common GI symptoms and are found in many commercial products including yogurt, juices, soy products, fermented milk, tempeh and other dietary supplements. They also come in capsule, tablet or powder formulations.
Probiotic Therapy Reduce the Incidence of Antibiotic Associated Diarrhea
Antibiotic-associated diarrhea (AAD) and Clostridium difficile-associated diarrhea (CDAD) are complications of long-term antibiotic use and are associated with significant cost and morbidity.
While the role of probiotics in treating AAD and CDAD has been investigated in several trials with conflicting results, this review, "Probiotic Prophylaxis Significantly Reduces the Incidence of Antibiotic Associated Diarrhea: A Meta-Analysis," by researchers from the Maimonides Medical Center in Brooklyn, New York, is the first meta-analysis examining the role of probiotics in treating these conditions.
Twenty-two studies were identified and a total of 3096 patients were included, 63 percent of whom were adults and all treated with various species of probiotics. Four studies (35 percent of the population of the study) used S. boulardii as the probiotic of choice. The average treatment period with probiotics was 1.5 weeks, with the shortest period being five days and the longest period being three weeks, according to Steven Shamah, MD, who presented the findings.
"Overall in twenty-two studies, probiotic prophylaxis significantly reduced the odds ratio of developing AAD by approximately 60 percent. This analysis clearly demonstrates that probiotics offer protective benefit in the prevention of these diseases," said principal investigator Rabin Rahmani, MD.
"These findings suggest that all patients who are at high-risk for these infections demonstrated by recent antibiotic useage, old age, recent hospitalization, low albumin, and immunosuppression should be considered for probiotic therapy," said Dr. Shamah. He added that further prospective studies are warranted to examine the most efficacious duration, dose and specific species of probiotics in prevention of AAD and CDAD in high risk patients.
Another related meta-analysis, "Probiotics in Antibiotic-Associated Diarrhea: An Updated Meta-Analysis of Randomized Controlled Trials," confirmed earlier results suggesting the preventative effects of probiotics in AAD. Researchers from Beth Israel Deaconess Medical Center, Harvard Medical School, aimed to estimate the reduction in risk of developing AAD with probiotic therapy in randomized controlled trials (RCT), and identify factors associated with such reduction. The analysis included 28 randomized controlled trials with 3,338 total patients receiving single or combination antibiotics for various indications.
"The preventive effect of probiotic use remained significant regardless of species used, adult versus child populations, study quality score and antibiotic administered," said researcher Elizabeth Videlock, MD, who presented the findings. "The preventive effect of probiotics is also apparent during combined antibiotic treatment for H.pylori eradication."
B. infantis 35624 Investigated in Non-Patient Population
In the largest study on probiotics done in the United States in a non-patient population, researchers from the University of North Carolina at Chapel Hill assessed the efficacy of B. infantis 35624--a probiotic that has been effective in relieving symptoms in IBS patients—for the relief of abdominal discomfort and bloating in a non-patient population.
The double-blind, randomized, placebo controlled, parallel study with a two-week placebo run-in phase followed by a four-week intervention phase was conducted at ten clinical centers in the US. The study included 302 non-patients who experienced abdominal discomfort and bloating more than twice weekly on average for at least three months but had not seen a physician or received prescribed medication for their symptoms in the past 12 months. They called in daily to report symptom severity on a six point Likert scale during the run-in and treatment phase.
Although mean severity scores for both, abdominal discomfort and bloating improved during the intervention period, there were no significant differences between the placebo and probiotic group, according to Yehuda Ringel, MD, who presented the findings.
"Unlike previous clinical studies in IBS patients, we were not able to demonstrate a statistically significant improvement in mean severity of abdominal discomfort and bloating with B. infantis 35624 in a non-patient population," said Dr. Ringel. He attributed this in part to the high placebo response and the possible "floor effect" which means the severity of symptoms is too low to measure any improvement. "This doesn't mean that B. infantis 35624 cannot help ease abdominal discomfort and bloating in non-patients—we just couldn't demonstrate it because the room for improvement is low compared to IBS patients, where symptom severity is much higher. Our secondary finding of significantly more bloating-free days in the B. infantis 35624 group needs further studies, particularly in the non-patient, healthy population."
Probiotic B. infantis 35624 Promising as Anti-Inflammatory Agent for Patients with Ulcerative Colitis, Psoriasis, Chronic Fatigue Syndrome
Microbial imbalance has been proposed as one possible explanation for the increased incidence of a wide range of inflammatory disorders, including ulcerative colitis, suggesting that altering the balance between good and bad bacteria in the gut may promote an immune regulatory response that could reduce inflammation, according to researchers at the Alimentary Pharmabiotic Centre at University College Cork and Alimentary Health Ltd in Cork, Ireland, who aimed to determine if B. infantis could influence systemic pro-inflammatory biomarkers in patients with inflammatory disease.
The double-blind, placebo controlled study, "Oral Administration of the Probiotic Bifidobacterium Infantis 35624 to Humans Induces Immunoregulatory Responses in Vivo," included healthy volunteers, and patients with psoriasis, ulcerative colitis and chronic fatigue syndrome. According to the results, plasma levels of the anti-inflammatory cytokine, IL-10, were significantly increased in healthy volunteers and psoriasis patients, but not placebo for eight weeks; while plasma levels of the pro-inflammatory cytokines TNF-alpha and IL-6 were significantly reduced in all patient groups that received B. infantis. In addition, C-reactive protein (CRP) levels were also significantly reduced in psoriasis, ulcerative colitis and chronic fatigue patients at the end of treatment with B. infantis compared to placebo treated patients.
"The human immunological response to B. infantis further supports the hypothesis that manipulation of the microbiota with specific therapeutic microbes can have a significant effect on host inflammatory processes," said Eamonn M.M. Quigley, MD, FACG, who presented the findings. "This anti-inflammatory effect is not restricted to a specific disease state, suggesting that B.infantis induces a critical cellular response, which may include the induction of regulatory cell subsets."
Monday, October 31, 2011
Moderate alcohol consumption is associated with GI woes
Just one drink per day may be cause of bloating, gas, abdominal pain, diarrhea
Just one drink per day for women -- two for men -- could lead to small intestinal bacterial overgrowth (SIBO) and subsequently cause gastrointestinal symptoms like bloating, gas, abdominal pain, constipation and diarrhea, according to the results of a new study unveiled today at the American College of Gastroenterology's (ACG) 76th Annual Scientific meeting in Washington, DC.
The retrospective review, "Moderate Alcohol Consumption is Associated with Small Intestinal Bacterial Overgrowth," looked at the charts of 198 patients who underwent lactulose hydrogen breath testing (LHBT) to determine the presence of SIBO, and found that any current alcohol consumption was significantly associated with the presence of SIBO -- and neither smoking nor use of heartburn drugs called PPIs was associated with an increased risk of SIBO.
Small intestinal bacterial overgrowth is a condition where abnormally large numbers of bacteria grow in the small intestine. Normally the small intestine contains a relatively low number of bacteria in contrast to the large intestine, which should contain a larger number of bacteria. In patients with SIBO, the abnormally large numbers of bacteria in the small intestine use for their growth many of the nutrients that would otherwise be absorbed.
As a result, a person with small bowel bacterial overgrowth may not absorb enough nutrients and become malnourished. In addition, the breakdown of nutrients by the bacteria in the small intestines can produce gas as well as lead to a change in bowel habits.
While previous studies have focused on alcoholics, who were found to have high rates of SIBO, this study by Scott Gabbard, MD and colleagues at the Dartmouth-Hitchcock Medical Center and the Mayo Clinic, is one of the first to look at the relationship between moderate alcohol consumption and SIBO. Moderate alcohol consumption means no more than 1 drink per day for women and 2 drinks per day for men, with twelve ounces of regular beer, 5 ounces of wine, or 1-½ ounces of 80-proof distilled spirits counting as one drink, according to the USDA dietary guidelines.
An overwhelming majority (95 percent) of the 198 patients in the study drank a moderate amount of alcohol, sometimes less than 1 drink per day, said Dr. Gabbard, who also indicated that only four of the patients drank more alcohol -- a finding he noted indicates that consumption of even the slightest amount of alcohol could have an impact on gut health.
"These findings are significant because we now know that any bit of alcohol consumption -- not just the amount consumed by alcoholics -- is a strong predictor of a positive lactulose hydrogen breath testing and small intestinal bacterial overgrowth," he said. "While typical treatment for SIBO has been antibiotics, probiotics or a combination of the two, the question now becomes what is the exact association between moderate alcohol consumption and SIBO and whether alcohol cessation can be used as a treatment for this potentially harmful condition."
Live longer with fewer calories
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By consuming fewer calories, ageing can be slowed down and the development of age-related diseases such as cancer and type 2 diabetes can be delayed. The earlier calorie intake is reduced, the greater the effect. Researchers at the University of Gothenburg have now identified one of the enzymes that hold the key to the ageing process.
"We are able to show that caloric restriction slows down ageing by preventing an enzyme, peroxiredoxin, from being inactivated. This enzyme is also extremely important in counteracting damage to our genetic material," says Mikael Molin of the Department of Cell and Molecular Biology.
By gradually reducing the intake of sugar and proteins, without reducing vitamins and minerals, researchers have previously shown that monkeys can live several years longer than expected. The method has also been tested on everything from fishes and rats to fungi, flies and yeasts with favourable results. Caloric restriction also has favourable effects on our health and delays the development of age-related diseases. Despite this, researchers in the field have found it difficult to explain exactly how caloric restriction produces these favourable effects.
Using yeast cells as a model, the research team at the University of Gothenburg has successfully identified one of the enzymes required. They are able to show that active peroxiredoxin 1, Prx1, an enzyme that breaks down harmful hydrogen peroxide in the cells, is required for caloric restriction to work effectively.
IMAGE: This is an image of yeast.
Click here for more information.
The results, which have been published in the scientific journal Molecular Cell, show that Prx1 is damaged during ageing and loses its activity. Caloric restriction counteracts this by increasing the production of another enzyme, Srx1, which repairs Prx1. Interestingly, the study also shows that ageing can be delayed without caloric restriction by only increasing the quantity of Srx1 in the cell. Repair of the peroxiredoxin Prx1 consequently emerges as a key process in ageing.
"Impaired Prx1 function leads to various types of genetic defects and cancer. Conversely, we can now speculate whether increased repair of Prx1 during ageing can counteract, or at least delay, the development of cancer."
Peroxiredoxins have also been shown to be capable of preventing proteins from being damaged and aggregating, a process that has been linked to several age-related disorders affecting the nervous system, such as Alzheimer's and Parkinson's. The researchers are accordingly also considering whether stimulation of Prx1 can reduce and delay such disease processes.
By consuming fewer calories, ageing can be slowed down and the development of age-related diseases such as cancer and type 2 diabetes can be delayed. The earlier calorie intake is reduced, the greater the effect. Researchers at the University of Gothenburg have now identified one of the enzymes that hold the key to the ageing process.
"We are able to show that caloric restriction slows down ageing by preventing an enzyme, peroxiredoxin, from being inactivated. This enzyme is also extremely important in counteracting damage to our genetic material," says Mikael Molin of the Department of Cell and Molecular Biology.
By gradually reducing the intake of sugar and proteins, without reducing vitamins and minerals, researchers have previously shown that monkeys can live several years longer than expected. The method has also been tested on everything from fishes and rats to fungi, flies and yeasts with favourable results. Caloric restriction also has favourable effects on our health and delays the development of age-related diseases. Despite this, researchers in the field have found it difficult to explain exactly how caloric restriction produces these favourable effects.
Using yeast cells as a model, the research team at the University of Gothenburg has successfully identified one of the enzymes required. They are able to show that active peroxiredoxin 1, Prx1, an enzyme that breaks down harmful hydrogen peroxide in the cells, is required for caloric restriction to work effectively.
IMAGE: This is an image of yeast.
Click here for more information.
The results, which have been published in the scientific journal Molecular Cell, show that Prx1 is damaged during ageing and loses its activity. Caloric restriction counteracts this by increasing the production of another enzyme, Srx1, which repairs Prx1. Interestingly, the study also shows that ageing can be delayed without caloric restriction by only increasing the quantity of Srx1 in the cell. Repair of the peroxiredoxin Prx1 consequently emerges as a key process in ageing.
"Impaired Prx1 function leads to various types of genetic defects and cancer. Conversely, we can now speculate whether increased repair of Prx1 during ageing can counteract, or at least delay, the development of cancer."
Peroxiredoxins have also been shown to be capable of preventing proteins from being damaged and aggregating, a process that has been linked to several age-related disorders affecting the nervous system, such as Alzheimer's and Parkinson's. The researchers are accordingly also considering whether stimulation of Prx1 can reduce and delay such disease processes.
Saturday, October 29, 2011
Jon's Health Tips - Latest Health Research
Wow - it's been a busy three weeks health news wise - so I will use a short-hand approach to much of this report (click on links for details):
Things I do that are good for me:
Regular aspirin intake halves hereditary cancer risk
Strawberries Protect the Stomach from Alcohol
Exercise Eases Arthritis
Diet lower in fat and higher in fiber may lower risk for chronic disease
Watermelon reduces atherosclerosis
Low fat diet with fish oil slowed growth of human prostate cancer cells
Consumption of black tea and fruit may protect against lung cancer
Physical fitness = reduced risk of glaucoma
Light drinking = significant decrease in cancer risk
Early mortality risk reduced up to 40 percent through increased physical activity and sports
Omega-3 fatty acids shown to prevent or slow progression of osteoarthritis
Eating green veggies improves immune defenses
Exercise Just as Good as Drugs at Preventing Migraines
Eating Fruits and Raw Vegetables Can Change the Effect of Your Genes
Health benefits of broccoli require the whole food, not supplements
Statins reduce severity of head injuries
Things I don't do that would be good for me:
Coffee consumption associated with decreased risk for basal cell carcinoma
Soy protein improves lipid profile in healthy individuals
Things that are bad for me:
I don't take Tylenol and I limit my use of Advil to really bad headaches:
Analgesics Use Associated With Increased Risk for Renal Cell Carcinoma
I try to keep my stress levels down, but it doesn't always work:
HIGH TO MODERATE LEVELS OF STRESS LEAD TO HIGHER MORTALITY RATE
I stopped taking Vitamin E quite a while ago, but this is scary:
Increased prostate cancer risk from vitamin E supplements
I don't take any of the herbal supplements listed here (or any other herbal supplements), but still worry about the supplements I do take:
Herbal Supplements May Cause Dangerous Drug Interactions
Things I hardly ever do, but could do more of without risk:
Biggest ever study shows no link between mobile phone use and tumors
This is really weird - (fish bad, high fat dairy good?) I don't know quite what to make of it. One possibility - a lot of the fish consumed was fried, and accompanied by french fries.
Dietary Patterns = Increased Colorectal Cancer Risk in Women
I don't agree with this article because it lumps in all supplements (such as Omega 3 oil, Co-enzyme Q, and alpha lipoic acid, all of which I take) with vitamins, and, as the commenters point out, ignores the importance of taking Vitamin D (the only vitamin I take) supplements:
Is This the End of Popping Vitamins?
Things I do that are good for me:
Regular aspirin intake halves hereditary cancer risk
Strawberries Protect the Stomach from Alcohol
Exercise Eases Arthritis
Diet lower in fat and higher in fiber may lower risk for chronic disease
Watermelon reduces atherosclerosis
Low fat diet with fish oil slowed growth of human prostate cancer cells
Consumption of black tea and fruit may protect against lung cancer
Physical fitness = reduced risk of glaucoma
Light drinking = significant decrease in cancer risk
Early mortality risk reduced up to 40 percent through increased physical activity and sports
Omega-3 fatty acids shown to prevent or slow progression of osteoarthritis
Eating green veggies improves immune defenses
Exercise Just as Good as Drugs at Preventing Migraines
Eating Fruits and Raw Vegetables Can Change the Effect of Your Genes
The researchers discovered the gene that is the strongest marker for heart disease can actually be modified by generous amounts of fruit and raw vegetables.
Health benefits of broccoli require the whole food, not supplements
Statins reduce severity of head injuries
Things I don't do that would be good for me:
Coffee consumption associated with decreased risk for basal cell carcinoma
Soy protein improves lipid profile in healthy individuals
Things that are bad for me:
I don't take Tylenol and I limit my use of Advil to really bad headaches:
Analgesics Use Associated With Increased Risk for Renal Cell Carcinoma
Use of acetaminophen (Tylenol) and nonaspirin nonsteroidal anti-inflammatory drugs (including Advil) was associated with a significantly increased risk for developing renal cell carcinoma, according to data presented at the 10th AACR International Conference on Frontiers in Cancer Prevention Research, held Oct. 22-25, 2011. It has previously been reported that people who take nonsteroidal anti-inflammatory drugs (NSAIDs) (other than aspirin) such as ibuprofen (Advil) may have a higher risk of having a heart attack or a stroke than people who do not take these medications.
I try to keep my stress levels down, but it doesn't always work:
HIGH TO MODERATE LEVELS OF STRESS LEAD TO HIGHER MORTALITY RATE
A new study concludes that men who experience persistently moderate or high levels of stressful life events over a number of years have a 50 percent higher mortality rate.
In general, the researchers found only a few protective factors against these higher levels of stress – people who self-reported that they had good health tended to live longer and married men also fared better. Moderate drinkers also lived longer than non-drinkers.
I stopped taking Vitamin E quite a while ago, but this is scary:
Increased prostate cancer risk from vitamin E supplements
I don't take any of the herbal supplements listed here (or any other herbal supplements), but still worry about the supplements I do take:
Herbal Supplements May Cause Dangerous Drug Interactions
Things I hardly ever do, but could do more of without risk:
Biggest ever study shows no link between mobile phone use and tumors
This is really weird - (fish bad, high fat dairy good?) I don't know quite what to make of it. One possibility - a lot of the fish consumed was fried, and accompanied by french fries.
Dietary Patterns = Increased Colorectal Cancer Risk in Women
The researchers found that those women who most often consumed high amounts of red meat, fish and sugar-sweetened beverages and low amounts of high-fat dairy, coffee and whole grains had a 35 percent increased risk for colorectal cancer.
I don't agree with this article because it lumps in all supplements (such as Omega 3 oil, Co-enzyme Q, and alpha lipoic acid, all of which I take) with vitamins, and, as the commenters point out, ignores the importance of taking Vitamin D (the only vitamin I take) supplements:
Is This the End of Popping Vitamins?
The case for dietary supplements is collapsing.
A succession of large-scale human studies, including two published earlier this month in leading medical journals, suggests that multivitamins and many other dietary supplements often don't have health benefits—and in some cases may even cause harm.
Friday, October 28, 2011
Regular aspirin intake halves cancer risk
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Scientists have discovered that taking regular aspirin halves the risk of developing hereditary cancers.
Hereditary cancers are those which develop as a result of a gene fault inherited from a parent. Bowel and womb cancers are the most common forms of hereditary cancers. Fifty thousand people in the UK are diagnosed with bowel and womb cancers every year; 10 per cent of these cancers are thought to be hereditary.
The decade-long study, which involved scientists and clinicians from 43 centres in 16 countries and was funded by Cancer Research UK, followed nearly 1,000 patients, in some cases for over 10 years. The study found that those who had been taking a regular dose of aspirin had 50 per cent fewer incidences of hereditary cancer compared with those who were not taking aspirin.
The research focused on people with Lynch syndrome which is an inherited genetic disorder that causes cancer by affecting genes responsible for detecting and repairing damage in the DNA. Around 50 per cent of those with Lynch syndrome develop cancer, mainly in the bowel and womb. The study looked at all cancers related to the syndrome, and found that almost 30 per cent of the patients not taking aspirin had developed a cancer compared to around 15 per cent of those taking the aspirin.
Those who had taken aspirin still developed the same number of polyps, which are thought to be precursors of cancer, as those who did not take aspirin but they did not go on to develop cancer. It suggests that aspirin could possibly be causing these cells to destruct before they turn cancerous.
Over 1,000 people were diagnosed with bowel cancer in Northern Ireland last year; 400 of these died from the disease. Ten per cent of bowel cancer cases are hereditary and by taking aspirin regularly the number of those dying from the hereditary form of the disease could be halved.
Professor Patrick Morrison from Queen's University in Belfast, who led the Northern Ireland part of the study, said: "The results of this study, which has been ongoing for over a decade, proves that the regular intake of aspirin over a prolonged period halves the risk of developing hereditary cancers. The effects of aspirin in the first five years of the study were not clear but in those who took aspirin for between five and ten years the results were very clear."
"This is a huge breakthrough in terms of cancer prevention. For those who have a history of hereditary cancers in their family, like bowel and womb cancers, this will be welcome news. Not only does it show we can reduce cancer rates and ultimately deaths, it opens up other avenues for further cancer prevention research. We aim now to go forward with another trial to assess the most effective dosage of aspirin for hereditary cancer prevention and to look at the use of aspirin in the general population as a way of reducing the risk of bowel cancer.
"For anyone considering taking aspirin I would recommend discussing this with your GP first as aspirin is known to bring with it a risk of stomach complaints, including ulcers." The research is due to be published in the Lancet Online on Oct. 28 2011.
Scientists have discovered that taking regular aspirin halves the risk of developing hereditary cancers.
Hereditary cancers are those which develop as a result of a gene fault inherited from a parent. Bowel and womb cancers are the most common forms of hereditary cancers. Fifty thousand people in the UK are diagnosed with bowel and womb cancers every year; 10 per cent of these cancers are thought to be hereditary.
The decade-long study, which involved scientists and clinicians from 43 centres in 16 countries and was funded by Cancer Research UK, followed nearly 1,000 patients, in some cases for over 10 years. The study found that those who had been taking a regular dose of aspirin had 50 per cent fewer incidences of hereditary cancer compared with those who were not taking aspirin.
The research focused on people with Lynch syndrome which is an inherited genetic disorder that causes cancer by affecting genes responsible for detecting and repairing damage in the DNA. Around 50 per cent of those with Lynch syndrome develop cancer, mainly in the bowel and womb. The study looked at all cancers related to the syndrome, and found that almost 30 per cent of the patients not taking aspirin had developed a cancer compared to around 15 per cent of those taking the aspirin.
Those who had taken aspirin still developed the same number of polyps, which are thought to be precursors of cancer, as those who did not take aspirin but they did not go on to develop cancer. It suggests that aspirin could possibly be causing these cells to destruct before they turn cancerous.
Over 1,000 people were diagnosed with bowel cancer in Northern Ireland last year; 400 of these died from the disease. Ten per cent of bowel cancer cases are hereditary and by taking aspirin regularly the number of those dying from the hereditary form of the disease could be halved.
Professor Patrick Morrison from Queen's University in Belfast, who led the Northern Ireland part of the study, said: "The results of this study, which has been ongoing for over a decade, proves that the regular intake of aspirin over a prolonged period halves the risk of developing hereditary cancers. The effects of aspirin in the first five years of the study were not clear but in those who took aspirin for between five and ten years the results were very clear."
"This is a huge breakthrough in terms of cancer prevention. For those who have a history of hereditary cancers in their family, like bowel and womb cancers, this will be welcome news. Not only does it show we can reduce cancer rates and ultimately deaths, it opens up other avenues for further cancer prevention research. We aim now to go forward with another trial to assess the most effective dosage of aspirin for hereditary cancer prevention and to look at the use of aspirin in the general population as a way of reducing the risk of bowel cancer.
"For anyone considering taking aspirin I would recommend discussing this with your GP first as aspirin is known to bring with it a risk of stomach complaints, including ulcers." The research is due to be published in the Lancet Online on Oct. 28 2011.
Strawberries Protect the Stomach from Alcohol
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In an experiment on rats, European researchers have proved that eating strawberries reduces the harm that alcohol can cause to the stomach mucous membrane. Published in the open access journal PLoS ONE, the study may contribute to improving the treatment of stomach ulcers.
A team of Italian, Serbian and Spanish researchers has confirmed the protecting effect that strawberries have in a mammal stomach that has been damaged by alcohol. Scientists gave ethanol (ethyl alcohol) to laboratory rats and, according to the study published in the journal PLoS ONE, have thus proved that the stomach mucous membrane of those that had previously eaten strawberry extract suffered less damage.
Sara Tulipani, researcher at the University of Barcelona (UB) and co-author of the study explains that "the positive effects of strawberries are not only linked to their antioxidant capacity and high content of phenolic compounds (anthocyans) but also to the fact that they activate the antioxidant defences and enzymes of the body."
The conclusions of the study state that a diet rich in strawberries can have a beneficial effect when it comes to preventing gastric illnesses that are related to the generation of free radicals or other reactive oxygen species. This fruit could slow down the formation of stomach ulcers in humans.
Gastritis or inflammation of the stomach mucous membrane is related to alcohol consumption but can also be caused by viral infections or by nonsteroidal anti-inflammatory medication (such as aspirin) or medication used to treat against the Helicobacter pylori bacteria.
Maurizio Battino, coordinator of the research group at the Marche Polytechnic University (UNIVPM, Italy) suggests that "in these cases, the consumption of strawberries during or after pathology could lessen stomach mucous membrane damage."
Less ulcerations after eating strawberries
The team found less ulcerations in the stomachs of those rats which had eaten strawberry extract (40 milligrams/day per kilo of weight) for 10 days before being given alcohol.
Battino emphasises that "this study was not conceived as a way of mitigating the effects of getting drunk but rather as a way of discovering molecules in the stomach membrane that protect against the damaging effects of differing agents."
Treatments for ulcers and other gastric pathologies are currently in need of new protective medicines with antioxidant properties. The compounds found within strawberries could be the answer.
In an experiment on rats, European researchers have proved that eating strawberries reduces the harm that alcohol can cause to the stomach mucous membrane. Published in the open access journal PLoS ONE, the study may contribute to improving the treatment of stomach ulcers.
A team of Italian, Serbian and Spanish researchers has confirmed the protecting effect that strawberries have in a mammal stomach that has been damaged by alcohol. Scientists gave ethanol (ethyl alcohol) to laboratory rats and, according to the study published in the journal PLoS ONE, have thus proved that the stomach mucous membrane of those that had previously eaten strawberry extract suffered less damage.
Sara Tulipani, researcher at the University of Barcelona (UB) and co-author of the study explains that "the positive effects of strawberries are not only linked to their antioxidant capacity and high content of phenolic compounds (anthocyans) but also to the fact that they activate the antioxidant defences and enzymes of the body."
The conclusions of the study state that a diet rich in strawberries can have a beneficial effect when it comes to preventing gastric illnesses that are related to the generation of free radicals or other reactive oxygen species. This fruit could slow down the formation of stomach ulcers in humans.
Gastritis or inflammation of the stomach mucous membrane is related to alcohol consumption but can also be caused by viral infections or by nonsteroidal anti-inflammatory medication (such as aspirin) or medication used to treat against the Helicobacter pylori bacteria.
Maurizio Battino, coordinator of the research group at the Marche Polytechnic University (UNIVPM, Italy) suggests that "in these cases, the consumption of strawberries during or after pathology could lessen stomach mucous membrane damage."
Less ulcerations after eating strawberries
The team found less ulcerations in the stomachs of those rats which had eaten strawberry extract (40 milligrams/day per kilo of weight) for 10 days before being given alcohol.
Battino emphasises that "this study was not conceived as a way of mitigating the effects of getting drunk but rather as a way of discovering molecules in the stomach membrane that protect against the damaging effects of differing agents."
Treatments for ulcers and other gastric pathologies are currently in need of new protective medicines with antioxidant properties. The compounds found within strawberries could be the answer.
Exercise Eases Arthritis
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Adding another incentive to exercise, scientists at Duke University Medical Center have found that physical activity improves arthritis symptoms even among obese mice that continue to chow down on a high-fat diet.
The insight suggests that excess weight alone isn't what causes the aches and pains of osteoarthritis, despite the long-held notion that carrying extra pounds strains the joints and leads to the inflammatory condition.
Published Sept. 27 online in the journal Arthritis & Rheumatism, the findings are now being tested in people.
"What's surprising is that exercise, without substantial weight loss, can be beneficial to the joints," said Farshid Guilak, Ph.D., professor of orthopaedic surgery at Duke and senior author of the study. "Ideally, it would be best to be fit and lose a little weight, but this shows that exercise alone can improve the health of your joints."
Even modest improvements could have a major impact if the findings are borne out in people. The Arthritis Foundation reports that one in five adults in the United States have been diagnosed with arthritis, and the annual cost of treating it and other rheumatic conditions has been tabbed at $128 billion.
Many cases of arthritis are associated with obesity and inactivity, so the Duke researchers set out to determine whether a high fat diet induces knee osteoarthritis, and then whether exercise provides a protective effect.
Using two sets of male mice -- half fed a high-fat diet and the other fed regular chow -- the researchers noted significant differences among the two groups. The mice on the high-fat food gained weight rapidly, processed glucose poorly and had much higher blood levels of molecules that trigger the chronic inflammation associated with osteoarthritis.
But when these animals got regular running wheel workouts, many of the harmful effects diminished -- even though the mice ate the same high-fat food and shed no weight. Glucose tolerance improved, while the inflammatory response was disrupted among key signaling molecules called cytokines, easing the development of arthritis.
If the extra weight on the joints had been the cause of the arthritis, the researchers noted, exercise would have exacerbated the problem. Instead, it helped.
"We're trying to understand the interaction of physical activity and obesity," said Timothy M. Griffin, Ph.D., lead author of the study. Griffin was formerly at Duke and is now at the Oklahoma Medical Research Foundation. "Even though there was the same amount of body fat, the fat was different."
Griffin said the fat cells still produced inflammatory molecules associated with arthritis, but they lost their punch because they could not organize into a force: "I don't want to say exercise is turning off that inflammatory signal, it just impairs it."
The findings add to a growing body of research exploring fitness vs. fatness. Ongoing studies at Duke and elsewhere are examining the role of diet, exercise and inflammatory diseases.
"This shows that if you are obese, it's better to exercise," Guilak said. "Sometimes pain can be a barrier to starting exercise, but if you overcome it, in the long term, it's better."
Adding another incentive to exercise, scientists at Duke University Medical Center have found that physical activity improves arthritis symptoms even among obese mice that continue to chow down on a high-fat diet.
The insight suggests that excess weight alone isn't what causes the aches and pains of osteoarthritis, despite the long-held notion that carrying extra pounds strains the joints and leads to the inflammatory condition.
Published Sept. 27 online in the journal Arthritis & Rheumatism, the findings are now being tested in people.
"What's surprising is that exercise, without substantial weight loss, can be beneficial to the joints," said Farshid Guilak, Ph.D., professor of orthopaedic surgery at Duke and senior author of the study. "Ideally, it would be best to be fit and lose a little weight, but this shows that exercise alone can improve the health of your joints."
Even modest improvements could have a major impact if the findings are borne out in people. The Arthritis Foundation reports that one in five adults in the United States have been diagnosed with arthritis, and the annual cost of treating it and other rheumatic conditions has been tabbed at $128 billion.
Many cases of arthritis are associated with obesity and inactivity, so the Duke researchers set out to determine whether a high fat diet induces knee osteoarthritis, and then whether exercise provides a protective effect.
Using two sets of male mice -- half fed a high-fat diet and the other fed regular chow -- the researchers noted significant differences among the two groups. The mice on the high-fat food gained weight rapidly, processed glucose poorly and had much higher blood levels of molecules that trigger the chronic inflammation associated with osteoarthritis.
But when these animals got regular running wheel workouts, many of the harmful effects diminished -- even though the mice ate the same high-fat food and shed no weight. Glucose tolerance improved, while the inflammatory response was disrupted among key signaling molecules called cytokines, easing the development of arthritis.
If the extra weight on the joints had been the cause of the arthritis, the researchers noted, exercise would have exacerbated the problem. Instead, it helped.
"We're trying to understand the interaction of physical activity and obesity," said Timothy M. Griffin, Ph.D., lead author of the study. Griffin was formerly at Duke and is now at the Oklahoma Medical Research Foundation. "Even though there was the same amount of body fat, the fat was different."
Griffin said the fat cells still produced inflammatory molecules associated with arthritis, but they lost their punch because they could not organize into a force: "I don't want to say exercise is turning off that inflammatory signal, it just impairs it."
The findings add to a growing body of research exploring fitness vs. fatness. Ongoing studies at Duke and elsewhere are examining the role of diet, exercise and inflammatory diseases.
"This shows that if you are obese, it's better to exercise," Guilak said. "Sometimes pain can be a barrier to starting exercise, but if you overcome it, in the long term, it's better."
Thursday, October 27, 2011
Childhood diet lower in fat and higher in fiber may lower risk for chronic disease in adulthood
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A recent study has found that a childhood behavioral intervention to lower dietary intake of total fat and saturated fat and increase consumption of foods that are good sources of dietary fiber resulted in significantly lower fasting plasma glucose levels and lower systolic blood pressure when study participants were re-evaluated in young adulthood. The study was accepted for publication in The Endocrine Society's Journal of Clinical Endocrinology and Metabolism (JCEM).
A Western dietary pattern high in total fat and saturated fatty acids and refined grains is associated with an increased risk of the metabolic syndrome, a cluster of metabolic abnormalities that include abdominal obesity, low levels of high-density lipoprotein cholesterol (sometimes considered "good cholesterol"), higher levels of triglycerides and blood glucose, and elevated blood pressure. This study evaluated the long-term effects of a dietary intervention to reduce fat and increase fiber intake during childhood on components of the metabolic syndrome in young adult women.
"This research is important because it suggests that modest reductions in total fat and saturated fat intake and increased consumption of dietary fiber during childhood and adolescence may have beneficial effects later in life by decreasing risk of chronic diseases such as diabetes and heart disease," said Joanne Dorgan, PhD, of Fox Chase Cancer Center in Philadelphia, PA and lead author of the study.
In this study, researchers evaluated 230 women between the ages of 25 and 29 years, who nine years before the current study participated in the Dietary Intervention Study in Children (DISC). DISC was a randomized controlled clinical trial of a reduced-fat dietary intervention that strived to limit fat intake to 28 percent of daily caloric intake and increase dietary fiber intake by encouraging consumption of fruits, vegetables and whole grains. The current study was conducted among females who had participated in the DISC trial to determine the longer-term effects of the DISC intervention.
Researchers measured body composition of study participants using whole body dual-energy x-ray absorptiometry (DXA) scans. Blood pressure was measured using automatic blood pressure monitors and blood samples were analyzed to assess levels of plasma glucose, cholesterol and triglycerides.
"Few participants in our follow-up study met the criteria for metabolic syndrome, however the intervention group had statistically significant lower mean systolic blood pressure and fasting plasma glucose levels compared to the control group," said Dorgan. "Significant differences at the follow-up visit, but not earlier, suggest that adolescent diet may have long-term effects on age-related changes in blood pressure and glycemic control that begin to become apparent in young adulthood. Longer follow-up studies of DISC participants are needed to determine if the differences found in this study persist or widen with increasing age."
A recent study has found that a childhood behavioral intervention to lower dietary intake of total fat and saturated fat and increase consumption of foods that are good sources of dietary fiber resulted in significantly lower fasting plasma glucose levels and lower systolic blood pressure when study participants were re-evaluated in young adulthood. The study was accepted for publication in The Endocrine Society's Journal of Clinical Endocrinology and Metabolism (JCEM).
A Western dietary pattern high in total fat and saturated fatty acids and refined grains is associated with an increased risk of the metabolic syndrome, a cluster of metabolic abnormalities that include abdominal obesity, low levels of high-density lipoprotein cholesterol (sometimes considered "good cholesterol"), higher levels of triglycerides and blood glucose, and elevated blood pressure. This study evaluated the long-term effects of a dietary intervention to reduce fat and increase fiber intake during childhood on components of the metabolic syndrome in young adult women.
"This research is important because it suggests that modest reductions in total fat and saturated fat intake and increased consumption of dietary fiber during childhood and adolescence may have beneficial effects later in life by decreasing risk of chronic diseases such as diabetes and heart disease," said Joanne Dorgan, PhD, of Fox Chase Cancer Center in Philadelphia, PA and lead author of the study.
In this study, researchers evaluated 230 women between the ages of 25 and 29 years, who nine years before the current study participated in the Dietary Intervention Study in Children (DISC). DISC was a randomized controlled clinical trial of a reduced-fat dietary intervention that strived to limit fat intake to 28 percent of daily caloric intake and increase dietary fiber intake by encouraging consumption of fruits, vegetables and whole grains. The current study was conducted among females who had participated in the DISC trial to determine the longer-term effects of the DISC intervention.
Researchers measured body composition of study participants using whole body dual-energy x-ray absorptiometry (DXA) scans. Blood pressure was measured using automatic blood pressure monitors and blood samples were analyzed to assess levels of plasma glucose, cholesterol and triglycerides.
"Few participants in our follow-up study met the criteria for metabolic syndrome, however the intervention group had statistically significant lower mean systolic blood pressure and fasting plasma glucose levels compared to the control group," said Dorgan. "Significant differences at the follow-up visit, but not earlier, suggest that adolescent diet may have long-term effects on age-related changes in blood pressure and glycemic control that begin to become apparent in young adulthood. Longer follow-up studies of DISC participants are needed to determine if the differences found in this study persist or widen with increasing age."
Watermelon reduces atherosclerosis
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In a recent study by University of Kentucky researchers, watermelon was shown to reduce atherosclerosis in animals.
The animal model used for the study involved mice with diet-induced high cholesterol. A control group was given water to drink, while the experimental group was given watermelon juice. By week eight of the study, the animals given watermelon juice had lower body weight than the control group, due to decrease of fat mass. They experienced no decrease in lean mass. Plasma cholesterol concentrations were significantly lower in the experimental group, with modestly reduced intermediate and low-density lipoprotein cholesterol concentrations as compared to the control group.
A measurement of atherosclerotic lesion areas revealed that the watermelon juice group also experienced statistically significant reductions in atherosclerotic lesions, as compared to the control group.
"Melons have many health benefits," said lead investigator Dr. Sibu Saha. "This pilot study has found three interesting health benefits in mouse model of atherosclerosis. Our ultimate goal is to identify bioactive compounds that would improve human health."
In a recent study by University of Kentucky researchers, watermelon was shown to reduce atherosclerosis in animals.
The animal model used for the study involved mice with diet-induced high cholesterol. A control group was given water to drink, while the experimental group was given watermelon juice. By week eight of the study, the animals given watermelon juice had lower body weight than the control group, due to decrease of fat mass. They experienced no decrease in lean mass. Plasma cholesterol concentrations were significantly lower in the experimental group, with modestly reduced intermediate and low-density lipoprotein cholesterol concentrations as compared to the control group.
A measurement of atherosclerotic lesion areas revealed that the watermelon juice group also experienced statistically significant reductions in atherosclerotic lesions, as compared to the control group.
"Melons have many health benefits," said lead investigator Dr. Sibu Saha. "This pilot study has found three interesting health benefits in mouse model of atherosclerosis. Our ultimate goal is to identify bioactive compounds that would improve human health."
Use of Over-the-Counter Thyroid Support Pills is Risky,
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People who use over-the-counter "thyroid support'' supplements may be putting their health at risk, according to a study being presented at the annual meeting of the American Thyroid Association. The supplements contain varying amounts of two different kinds of thyroid hormones apparently derived in large part from chopped up animal thyroid glands, says the study's senior investigator, Victor Bernet, M.D., an endocrinologist at Mayo Clinic in Florida.
The hormones are known as T3, or triiodothyronine, and T4, or thyroxine. They are regulated by the U.S. Food and Drug Administration and intended for use only in prescription medication because they can cause significant health issues, such as an increase in heart rate, heart irregularities and palpitations, nervousness, and diarrhea, Dr. Bernet says.
"These hormones have effects throughout the body, which is why they are controlled," he says.
Not only did nine of the 10 supplements studied have animal hormone, the amount of hormones in the products varied significantly, sometimes exceeding doses used for individual patients and comparable to levels found in prescription thyroid medication, Dr. Bernet says.
The supplements likely do not give most people the results they are seeking, such as weight loss or less fatigue, he says.
"The amount of thyroid hormone a normal person would have to take to lose weight would be dangerously high and there is no evidence that use of thyroid hormone effectively treats fatigue when used in people without actual hypothyroidism," he says.
Because physicians have seen a number of abnormal thyroid tests from patients using over-the-counter supplements, Dr. Bernet became interested in this issue when he heard reports of such cases as chairman of the American Thyroid Association's public health committee. He worked with researchers including endocrinologists at Walter Reed Army Medical Center, where he practiced at the time.
The researchers bought 10 commercially available thyroid supplements from stores or websites and used high-pressure liquid chromatography to separate and identify the chemical components of T3 and T4. Nine of the 10 contained T3 and five of them would deliver as much, or more, than 50 percent of the total amount of T3 produced by the body daily.
Four of the 10 supplements contained T4, and some of those contained a dose that could be twice as much as what an adult needs each day. Only one supplement had no detectable T3 or T4.
The results show there is a need for more effective monitoring of the contents of over-the-counter thyroid support products and more patient education about the products' potential health risks, Dr. Bernet says.
People who use over-the-counter "thyroid support'' supplements may be putting their health at risk, according to a study being presented at the annual meeting of the American Thyroid Association. The supplements contain varying amounts of two different kinds of thyroid hormones apparently derived in large part from chopped up animal thyroid glands, says the study's senior investigator, Victor Bernet, M.D., an endocrinologist at Mayo Clinic in Florida.
The hormones are known as T3, or triiodothyronine, and T4, or thyroxine. They are regulated by the U.S. Food and Drug Administration and intended for use only in prescription medication because they can cause significant health issues, such as an increase in heart rate, heart irregularities and palpitations, nervousness, and diarrhea, Dr. Bernet says.
"These hormones have effects throughout the body, which is why they are controlled," he says.
Not only did nine of the 10 supplements studied have animal hormone, the amount of hormones in the products varied significantly, sometimes exceeding doses used for individual patients and comparable to levels found in prescription thyroid medication, Dr. Bernet says.
The supplements likely do not give most people the results they are seeking, such as weight loss or less fatigue, he says.
"The amount of thyroid hormone a normal person would have to take to lose weight would be dangerously high and there is no evidence that use of thyroid hormone effectively treats fatigue when used in people without actual hypothyroidism," he says.
Because physicians have seen a number of abnormal thyroid tests from patients using over-the-counter supplements, Dr. Bernet became interested in this issue when he heard reports of such cases as chairman of the American Thyroid Association's public health committee. He worked with researchers including endocrinologists at Walter Reed Army Medical Center, where he practiced at the time.
The researchers bought 10 commercially available thyroid supplements from stores or websites and used high-pressure liquid chromatography to separate and identify the chemical components of T3 and T4. Nine of the 10 contained T3 and five of them would deliver as much, or more, than 50 percent of the total amount of T3 produced by the body daily.
Four of the 10 supplements contained T4, and some of those contained a dose that could be twice as much as what an adult needs each day. Only one supplement had no detectable T3 or T4.
The results show there is a need for more effective monitoring of the contents of over-the-counter thyroid support products and more patient education about the products' potential health risks, Dr. Bernet says.
Wednesday, October 26, 2011
Analgesics Use Associated With Increased Risk for Renal Cell Carcinoma
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Use of acetaminophen and nonaspirin nonsteroidal anti-inflammatory drugs was associated with a significantly increased risk for developing renal cell carcinoma, according to data presented at the 10th AACR International Conference on Frontiers in Cancer Prevention Research, held Oct. 22-25, 2011.
It has previously been reported that people who take nonsteroidal anti-inflammatory drugs (NSAIDs) (other than aspirin) such as ibuprofen (Advil) may have a higher risk of having a heart attack or a stroke than people who do not take these medications.
Eunyoung Cho, Sc.D., assistant professor of medicine at Harvard Medical School and associate epidemiologist at Brigham and Women's Hospital in Boston, and colleagues conducted a preliminary meta-analysis of 18 studies from six countries to examine analgesics use and its relation to the risk for renal cell carcinoma (RCC).
"Our meta-analysis was the largest analysis of analgesics and risk for RCC," Cho said. "Our study is the first few of those studies raising [the] possibility that these commonly used painkillers may elevate the risk for certain types of cancer."
Cho and colleagues conducted a Medline database search for case-control or cohort studies on acetaminophen, aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs), published between 1966 and July 1, 2011. They found 12 studies examining risk for acetaminophen, 12 for aspirin and five for NSAIDs.
Results demonstrated that any use of acetaminophen was associated with a 33 percent increased risk for RCC, and use of other NSAIDs was linked with a 26 percent increased risk. No significantly increased risk for RCC was found with the use of aspirin.
The meta-analysis revealed similar trends with high-dose analgesics intake. Researchers found no significant difference in associations based on study design, type of controls in case-control studies, study outcome or gender.
"The positive association with nonaspirin NSAIDs was somewhat expected since we recently published on the association from two prospective studies [in Archives of Internal Medicine], which were included in this meta-analysis," Cho said. "However, the association with use of acetaminophen was not found in the publication and was thus unexpected. Several relatively small studies of use of acetaminophen and RCC did suggest positive associations. When we conducted a meta-analysis of these studies to improve statistical power, the summary results came out statistically significant."
Use of acetaminophen and nonaspirin nonsteroidal anti-inflammatory drugs was associated with a significantly increased risk for developing renal cell carcinoma, according to data presented at the 10th AACR International Conference on Frontiers in Cancer Prevention Research, held Oct. 22-25, 2011.
It has previously been reported that people who take nonsteroidal anti-inflammatory drugs (NSAIDs) (other than aspirin) such as ibuprofen (Advil) may have a higher risk of having a heart attack or a stroke than people who do not take these medications.
Eunyoung Cho, Sc.D., assistant professor of medicine at Harvard Medical School and associate epidemiologist at Brigham and Women's Hospital in Boston, and colleagues conducted a preliminary meta-analysis of 18 studies from six countries to examine analgesics use and its relation to the risk for renal cell carcinoma (RCC).
"Our meta-analysis was the largest analysis of analgesics and risk for RCC," Cho said. "Our study is the first few of those studies raising [the] possibility that these commonly used painkillers may elevate the risk for certain types of cancer."
Cho and colleagues conducted a Medline database search for case-control or cohort studies on acetaminophen, aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs), published between 1966 and July 1, 2011. They found 12 studies examining risk for acetaminophen, 12 for aspirin and five for NSAIDs.
Results demonstrated that any use of acetaminophen was associated with a 33 percent increased risk for RCC, and use of other NSAIDs was linked with a 26 percent increased risk. No significantly increased risk for RCC was found with the use of aspirin.
The meta-analysis revealed similar trends with high-dose analgesics intake. Researchers found no significant difference in associations based on study design, type of controls in case-control studies, study outcome or gender.
"The positive association with nonaspirin NSAIDs was somewhat expected since we recently published on the association from two prospective studies [in Archives of Internal Medicine], which were included in this meta-analysis," Cho said. "However, the association with use of acetaminophen was not found in the publication and was thus unexpected. Several relatively small studies of use of acetaminophen and RCC did suggest positive associations. When we conducted a meta-analysis of these studies to improve statistical power, the summary results came out statistically significant."
Tuesday, October 25, 2011
Low fat diet with fish oil slowed growth of human prostate cancer cells
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A low-fat diet with fish oil supplements eaten for four to six weeks prior to prostate removal slowed down the growth of prostate cancer cells -- the number of rapidly dividing cells -- in human prostate cancer tissue compared to a traditional, high-fat Western diet.
Done by researchers at UCLA's Jonsson Comprehensive Cancer Center, the short-term study also found that the men on the low-fat, fish oil supplement diet were able to change the composition of their cell membranes in both the healthy cells and the cancer cells in the prostate. They had increased levels of omega-3 fatty acids from fish oil and decreased levels of omega-6 fatty acids from corn oil in the cell membranes, which may directly affect the biology of the cells, though further studies are needed, said Dr. William Aronson, the study's first author and a researcher with UCLA's Jonsson Comprehensive Cancer Center.
The study also found that blood obtained from patients after the low-fat, fish oil diet program slowed the growth of prostate cancer cells in a test tube as compared to blood from men on the Western diet, which did not slow cancer growth.
"The finding that the low-fat, fish oil diet reduced the number of rapidly dividing cells in the prostate cancer tissue is important because the rate at which the cells are dividing can be predictive of future cancer progression," Aronson said. "The lower the rate of proliferation, the lesser the chances that the cancer will spread outside the prostate, where it is much harder to treat."
The study appeared Oct. 25, 2011 in Cancer Prevention Research, a peer-reviewed journal of the American Association for Cancer Research.
The study, which evaluated blood samples before and after the diet commenced and examined tissue from the removed prostate, validated previous studies by Aronson and others done on cell lines and in animal models. Aronson said the study using human blood and tissue also proved that the changes prompted by what the men were eating were clearly evident in their prostate tissue - the "treatment" was indeed reaching the targeted organ because of the changes in the prostate cell membrane's fatty acid composition.
"You truly are what you eat," said Aronson, a clinical professor of urology, who also serves as chief of urologic oncology at the West Los Angeles Veterans Affairs Medical Center. "Based on our animal studies, we were hopeful that we would see the same effects in humans. We are extremely pleased about our findings, which suggest that by altering the diet, we may favorable affect the biology of prostate cancer."
Aronson measured proliferation, or the rate of prostate cancer cell division, by staining tissue obtained from the radical prostatectomy specimens with an antibody against Ki-67, a protein involved in the cell-cycle progression and growth.
"The percentage of prostate cancer cells that stained for Ki-67 was determined by the pathologist, and this gave us an objective measurement of the percentage of cells that were actively dividing and therefore more aggressive," said Aronson. "Previous studies found that patients with higher levels of Ki-67 in their prostate cancer tissue were more likely to have their prostate cancer progress to advanced stages, and were more likely to die from their prostate cancer. Thus, we are extremely encouraged by our findings that a low-fat diet with fish oil lowered Ki-67 levels and may have the potential to slow the progression of prostate cancer."
Diet studies often are difficult to evaluate because getting patients to comply with dietary changes can be challenging. However, the food eaten by men in both arms of this study was precisely controlled, Aronson said. The meals were prepared by chefs in the UCLA Clinical Translational Research Center and delivered in bulk to study participants several times a week. Participants also met with a dietician, kept food diaries and were required to return uneaten food.
"The key to this study was having the meals prepared and delivered to the study participants," Aronson said. "This resulted in a very high rate of compliance, making the study very well controlled."
The Western diet consisted of 40 percent of calories from fat, generally equivalent to what many Americans consume today. The fat sources also were typical of the American diet, and included high levels of omega-6 fatty acids from corn oil and low levels of fish oil that provide omega-3 fatty acids.
The low-fat diet consisted of 15 percent of calories from fat. Additionally, the men on this diet took five grams of fish oil per day in five capsules, three with breakfast and two with dinner, to provide fish oil omega-3 fatty acids. Omega-3 fatty acids have been found to reduce the incidence of heart disease and fight inflammation, and inflammation has been associated with certain cancers.
"Preclinical studies suggest that lowering dietary omega-6 fatty acids from corn oil and increasing omega-3 fatty acids from fish oil decreases the risk of prostate cancer development and progression," the study states. "We found this diet intervention resulted in a decrease in omega-6 vs. omega-3 fatty acid ratios in benign and malignant prostate tissue and a decrease in malignant cell proliferation."
Aronson cautioned that he could not recommend dietary changes based on this study because of its short duration and small sample size. However, based on these results he is organizing a much larger study of 100 men with prostate cancers who have elected active surveillance, meaning they're not getting any treatment for their disease but are getting regular biopsies and check-ups.
The future study will randomly divide the men into a low-fat, fish oil supplement group and a traditional Western diet group and follow them for a year to evaluate the diet effects on prostate cancer proliferation.
A low-fat diet with fish oil supplements eaten for four to six weeks prior to prostate removal slowed down the growth of prostate cancer cells -- the number of rapidly dividing cells -- in human prostate cancer tissue compared to a traditional, high-fat Western diet.
Done by researchers at UCLA's Jonsson Comprehensive Cancer Center, the short-term study also found that the men on the low-fat, fish oil supplement diet were able to change the composition of their cell membranes in both the healthy cells and the cancer cells in the prostate. They had increased levels of omega-3 fatty acids from fish oil and decreased levels of omega-6 fatty acids from corn oil in the cell membranes, which may directly affect the biology of the cells, though further studies are needed, said Dr. William Aronson, the study's first author and a researcher with UCLA's Jonsson Comprehensive Cancer Center.
The study also found that blood obtained from patients after the low-fat, fish oil diet program slowed the growth of prostate cancer cells in a test tube as compared to blood from men on the Western diet, which did not slow cancer growth.
"The finding that the low-fat, fish oil diet reduced the number of rapidly dividing cells in the prostate cancer tissue is important because the rate at which the cells are dividing can be predictive of future cancer progression," Aronson said. "The lower the rate of proliferation, the lesser the chances that the cancer will spread outside the prostate, where it is much harder to treat."
The study appeared Oct. 25, 2011 in Cancer Prevention Research, a peer-reviewed journal of the American Association for Cancer Research.
The study, which evaluated blood samples before and after the diet commenced and examined tissue from the removed prostate, validated previous studies by Aronson and others done on cell lines and in animal models. Aronson said the study using human blood and tissue also proved that the changes prompted by what the men were eating were clearly evident in their prostate tissue - the "treatment" was indeed reaching the targeted organ because of the changes in the prostate cell membrane's fatty acid composition.
"You truly are what you eat," said Aronson, a clinical professor of urology, who also serves as chief of urologic oncology at the West Los Angeles Veterans Affairs Medical Center. "Based on our animal studies, we were hopeful that we would see the same effects in humans. We are extremely pleased about our findings, which suggest that by altering the diet, we may favorable affect the biology of prostate cancer."
Aronson measured proliferation, or the rate of prostate cancer cell division, by staining tissue obtained from the radical prostatectomy specimens with an antibody against Ki-67, a protein involved in the cell-cycle progression and growth.
"The percentage of prostate cancer cells that stained for Ki-67 was determined by the pathologist, and this gave us an objective measurement of the percentage of cells that were actively dividing and therefore more aggressive," said Aronson. "Previous studies found that patients with higher levels of Ki-67 in their prostate cancer tissue were more likely to have their prostate cancer progress to advanced stages, and were more likely to die from their prostate cancer. Thus, we are extremely encouraged by our findings that a low-fat diet with fish oil lowered Ki-67 levels and may have the potential to slow the progression of prostate cancer."
Diet studies often are difficult to evaluate because getting patients to comply with dietary changes can be challenging. However, the food eaten by men in both arms of this study was precisely controlled, Aronson said. The meals were prepared by chefs in the UCLA Clinical Translational Research Center and delivered in bulk to study participants several times a week. Participants also met with a dietician, kept food diaries and were required to return uneaten food.
"The key to this study was having the meals prepared and delivered to the study participants," Aronson said. "This resulted in a very high rate of compliance, making the study very well controlled."
The Western diet consisted of 40 percent of calories from fat, generally equivalent to what many Americans consume today. The fat sources also were typical of the American diet, and included high levels of omega-6 fatty acids from corn oil and low levels of fish oil that provide omega-3 fatty acids.
The low-fat diet consisted of 15 percent of calories from fat. Additionally, the men on this diet took five grams of fish oil per day in five capsules, three with breakfast and two with dinner, to provide fish oil omega-3 fatty acids. Omega-3 fatty acids have been found to reduce the incidence of heart disease and fight inflammation, and inflammation has been associated with certain cancers.
"Preclinical studies suggest that lowering dietary omega-6 fatty acids from corn oil and increasing omega-3 fatty acids from fish oil decreases the risk of prostate cancer development and progression," the study states. "We found this diet intervention resulted in a decrease in omega-6 vs. omega-3 fatty acid ratios in benign and malignant prostate tissue and a decrease in malignant cell proliferation."
Aronson cautioned that he could not recommend dietary changes based on this study because of its short duration and small sample size. However, based on these results he is organizing a much larger study of 100 men with prostate cancers who have elected active surveillance, meaning they're not getting any treatment for their disease but are getting regular biopsies and check-ups.
The future study will randomly divide the men into a low-fat, fish oil supplement group and a traditional Western diet group and follow them for a year to evaluate the diet effects on prostate cancer proliferation.
Dietary Patterns = Increased Colorectal Cancer Risk in Women
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Researchers may have found a specific dietary pattern linked to levels of C-peptide concentrations that increase a woman's risk for colorectal cancer.
"High red meat intake, fish intake, sugar-sweetened beverage intake, but low coffee, whole grains and high-fat dairy intake, when taken as a whole, seemed to be associated with higher levels of C-peptide in the blood," said Teresa T. Fung, S.D., R.D., professor of nutrition at Simmons College in Boston, who presented the data at the 10th AACR International Conference on Frontiers in Cancer Prevention Research, held Oct. 22-25, 2011.
C-peptide is a marker of insulin secretion that can be measured in a person's blood. High levels of insulin may promote cell growth and multiplication. One of the major characteristics of cancer is aberrant cell growth. Higher levels of C-peptide, and therefore insulin, may promote cancer cell growth.
"Colon cancer seems to be one of the cancers that are sensitive to insulin," Fung said. "This research has helped us to put together a fuller picture of what may be going on in terms of mechanisms and the relationship between food and colorectal cancer risk."
Fung and colleagues surveyed a sample of women every two years about general health information including whether or not they had been diagnosed with colorectal cancer. The researchers also assessed women's diets in a separate questionnaire mailed to them every four years. The dietary questionnaire listed more than 130 types of foods and asked the women how often they were consuming each type.
After 22 years of follow-up, 985 cases of colorectal cancer and 758 cases of colon cancer were diagnosed among the women. The researchers found that those women who most often consumed high amounts of red meat, fish and sugar-sweetened beverages and low amounts of high-fat dairy, coffee and whole grains had a 35 percent increased risk for colorectal cancer.
The researchers also compared the dietary information of women who were lean and active with that of women who were overweight and sedentary.
"We found that people who were overweight or inactive seemed more sensitive to this dietary pattern. Their risk for colorectal cancer was much higher than those people who were lean and active," Fung said. "Overweight people are already at risk for insulin resistance. We think that if you then add this unique dietary pattern on top of that, which was associated with higher C-peptide levels, they are much more prone to develop colorectal cancer."
Fung said people should pay attention to the foods they consume for a multitude of health reasons.
"Although avoiding the dietary patterns that we found is not necessarily the most comprehensive way to prevent colorectal cancer, it definitely targets one pathway of the disease," she said.
Researchers may have found a specific dietary pattern linked to levels of C-peptide concentrations that increase a woman's risk for colorectal cancer.
"High red meat intake, fish intake, sugar-sweetened beverage intake, but low coffee, whole grains and high-fat dairy intake, when taken as a whole, seemed to be associated with higher levels of C-peptide in the blood," said Teresa T. Fung, S.D., R.D., professor of nutrition at Simmons College in Boston, who presented the data at the 10th AACR International Conference on Frontiers in Cancer Prevention Research, held Oct. 22-25, 2011.
C-peptide is a marker of insulin secretion that can be measured in a person's blood. High levels of insulin may promote cell growth and multiplication. One of the major characteristics of cancer is aberrant cell growth. Higher levels of C-peptide, and therefore insulin, may promote cancer cell growth.
"Colon cancer seems to be one of the cancers that are sensitive to insulin," Fung said. "This research has helped us to put together a fuller picture of what may be going on in terms of mechanisms and the relationship between food and colorectal cancer risk."
Fung and colleagues surveyed a sample of women every two years about general health information including whether or not they had been diagnosed with colorectal cancer. The researchers also assessed women's diets in a separate questionnaire mailed to them every four years. The dietary questionnaire listed more than 130 types of foods and asked the women how often they were consuming each type.
After 22 years of follow-up, 985 cases of colorectal cancer and 758 cases of colon cancer were diagnosed among the women. The researchers found that those women who most often consumed high amounts of red meat, fish and sugar-sweetened beverages and low amounts of high-fat dairy, coffee and whole grains had a 35 percent increased risk for colorectal cancer.
The researchers also compared the dietary information of women who were lean and active with that of women who were overweight and sedentary.
"We found that people who were overweight or inactive seemed more sensitive to this dietary pattern. Their risk for colorectal cancer was much higher than those people who were lean and active," Fung said. "Overweight people are already at risk for insulin resistance. We think that if you then add this unique dietary pattern on top of that, which was associated with higher C-peptide levels, they are much more prone to develop colorectal cancer."
Fung said people should pay attention to the foods they consume for a multitude of health reasons.
"Although avoiding the dietary patterns that we found is not necessarily the most comprehensive way to prevent colorectal cancer, it definitely targets one pathway of the disease," she said.
Monday, October 24, 2011
Consumption of black tea and fruit may protect against lung cancer
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Heavy alcohol consumption may be linked to a greater risk of developing lung cancer, while higher BMI and increased consumption of black tea and fruit are associated with lower risk of the deadly disease. In three separate studies presented at CHEST 2011, the 77th annual meeting of the American College of Chest Physicians (ACCP), heavy alcohol consumption was related to increased risk of lung cancer, while specific ethnic groups, including African American men and Asian women, had slightly higher risks for lung cancer. Conversely, black tea consumption was shown to reduce lung cancer risk in nonsmoking women, while higher BMI and increased fruit consumption were associated with a lower risk of lung cancer in both men and women.
Lung Cancer Risk Factors
“Heavy drinking has multiple harmful effects, including cardiovascular complications and increased risk for lung cancer, said Stanton Siu, MD, FCCP, Kaiser Permanente, Oakland, California. “We did not see a relationship between moderate drinking and lung cancer development. So it appears probable that most middle-aged and older moderate drinkers have coronary artery protection and no increased risk of lung cancer risk.”
Dr. Siu and his research team studied 126,293 people who provided baseline data from 1978 to1985 and followed them until 2008 to determine their risk for developing lung cancer in relation to cigarette smoking, alcohol consumption, gender, ethnicity, BMI, and level of education. Of the 1,852 people who developed lung cancer during this time, results showed that cigarette smoking remained a strong predictor of all types of lung cancer; however, heavy alcohol consumption (> 3 alcoholic drinks per day) also increased lung cancer risk, with a slightly higher risk related to heavy beer consumption as opposed to wine and liquor.
“Genetic variations among different ethnic groups could explain the elevated risk for lung cancer. Environmental exposures, occupation, and diet can also influence lung cancer risk,” said Dr. Siu.
Reduced Risk of Lung Cancer
Although researchers found several factors that increased lung cancer risk, other factors were found to be related to reduced risk of the disease. Dr. Siu and team found an inverse relationship between BMI and lung cancer risk, where higher BMI levels were associated with a lower risk for lung cancer. A similar relationship was seen in those who graduated from college.
“Explanations are not evident, but people with more education probably have a generally healthy lifestyle,” said Dr. Siu. “The BMI-cancer association was independent of smoking, and we speculate that nutritional factors may be involved.”
In a separate study also presented at CHEST, researchers from the Czech Republic investigated the relationship between smoking exposure, diet, and exercise, and the risk of lung cancer. They found that consumption of black tea had a protective effect on nonsmoking women, while fruit had a protective effect for both men and women.
“Smoking remains the primary risk factor for lung cancer, yet we can’t ignore other environmental or lifestyle factors that may impact one’s health,” said David Gutterman, MD, FCCP, President of the American College of Chest Physicians. “Quitting smoking or never starting can help to reduce lung cancer risk, as can living an overall active and healthy lifestyle.”
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Heavy alcohol consumption may be linked to a greater risk of developing lung cancer, while higher BMI and increased consumption of black tea and fruit are associated with lower risk of the deadly disease. In three separate studies presented at CHEST 2011, the 77th annual meeting of the American College of Chest Physicians (ACCP), heavy alcohol consumption was related to increased risk of lung cancer, while specific ethnic groups, including African American men and Asian women, had slightly higher risks for lung cancer. Conversely, black tea consumption was shown to reduce lung cancer risk in nonsmoking women, while higher BMI and increased fruit consumption were associated with a lower risk of lung cancer in both men and women.
Lung Cancer Risk Factors
“Heavy drinking has multiple harmful effects, including cardiovascular complications and increased risk for lung cancer, said Stanton Siu, MD, FCCP, Kaiser Permanente, Oakland, California. “We did not see a relationship between moderate drinking and lung cancer development. So it appears probable that most middle-aged and older moderate drinkers have coronary artery protection and no increased risk of lung cancer risk.”
Dr. Siu and his research team studied 126,293 people who provided baseline data from 1978 to1985 and followed them until 2008 to determine their risk for developing lung cancer in relation to cigarette smoking, alcohol consumption, gender, ethnicity, BMI, and level of education. Of the 1,852 people who developed lung cancer during this time, results showed that cigarette smoking remained a strong predictor of all types of lung cancer; however, heavy alcohol consumption (> 3 alcoholic drinks per day) also increased lung cancer risk, with a slightly higher risk related to heavy beer consumption as opposed to wine and liquor.
“Genetic variations among different ethnic groups could explain the elevated risk for lung cancer. Environmental exposures, occupation, and diet can also influence lung cancer risk,” said Dr. Siu.
Reduced Risk of Lung Cancer
Although researchers found several factors that increased lung cancer risk, other factors were found to be related to reduced risk of the disease. Dr. Siu and team found an inverse relationship between BMI and lung cancer risk, where higher BMI levels were associated with a lower risk for lung cancer. A similar relationship was seen in those who graduated from college.
“Explanations are not evident, but people with more education probably have a generally healthy lifestyle,” said Dr. Siu. “The BMI-cancer association was independent of smoking, and we speculate that nutritional factors may be involved.”
In a separate study also presented at CHEST, researchers from the Czech Republic investigated the relationship between smoking exposure, diet, and exercise, and the risk of lung cancer. They found that consumption of black tea had a protective effect on nonsmoking women, while fruit had a protective effect for both men and women.
“Smoking remains the primary risk factor for lung cancer, yet we can’t ignore other environmental or lifestyle factors that may impact one’s health,” said David Gutterman, MD, FCCP, President of the American College of Chest Physicians. “Quitting smoking or never starting can help to reduce lung cancer risk, as can living an overall active and healthy lifestyle.”
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Coffee consumption associated with decreased risk for basal cell carcinoma
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Caffeine could be related to an inverse association between basal cell carcinoma risk and consumption of coffee, a study found.
The prospective study, presented at the 10th AACR International Conference on Frontiers in Cancer Prevention Research, held Oct. 22-25, 2011, examined the risks of basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and melanoma in connection with coffee consumption and found a decreased risk for BCC only.
“Given the nearly 1 million new cases of BCC diagnosed each year in the United States, daily dietary factors with even small protective effects may have great public health impact,” said researcher Fengju Song, Ph.D., a postdoctoral fellow in the department of dermatology at Brigham and Women’s Hospital and Harvard Medical School. “Our study indicates that coffee consumption may be an important option to help prevent BCC.”
Data were taken from the Nurses’ Health Study (Brigham and Women’s Hospital) and the Health Professionals Follow-Up Study (Harvard School of Public Health). In the Nurses’ Health Study, 72,921 participants were followed from June 1984 to June 2008. In the Health Professionals Follow-Up Study, 39,976 participants were followed from June 1986 to June 2008.
The researchers reported 25,480 incident skin cancer cases. Of those, 22,786 were BCC, 1,953 were SCC, and 741 were melanoma.
Song and colleagues reported that women who consumed more than three cups of coffee per day had a 20 percent reduction in risk for BCC, and men who consumed more than three cups per day had a nine percent risk reduction compared with people who consumed less than one cup per month.
The amount of coffee consumption was inversely associated with BCC risk. Those in the highest quintile had the lowest risk, with an 18 percent reduction for women and a 13 percent reduction for men.
Song and colleagues were surprised by the inverse connection in BCC cases only. Animal studies have suggested an association between coffee intake and skin cancer risk, but epidemiologic studies have not conclusively shown the same results, they said.
“Mouse studies have shown that oral or topical caffeine promotes elimination of UV-damaged keratinocytes via apoptosis (programmed cell death) and markedly reduces subsequent SCC development,” Song said. “However, in our cohort analysis, we did not find any inverse association between coffee consumption and the risk for SCC.”
Song said that additional studies specifically addressing the association between coffee consumption and BCC and the mechanism behind this association are warranted.
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Caffeine could be related to an inverse association between basal cell carcinoma risk and consumption of coffee, a study found.
The prospective study, presented at the 10th AACR International Conference on Frontiers in Cancer Prevention Research, held Oct. 22-25, 2011, examined the risks of basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and melanoma in connection with coffee consumption and found a decreased risk for BCC only.
“Given the nearly 1 million new cases of BCC diagnosed each year in the United States, daily dietary factors with even small protective effects may have great public health impact,” said researcher Fengju Song, Ph.D., a postdoctoral fellow in the department of dermatology at Brigham and Women’s Hospital and Harvard Medical School. “Our study indicates that coffee consumption may be an important option to help prevent BCC.”
Data were taken from the Nurses’ Health Study (Brigham and Women’s Hospital) and the Health Professionals Follow-Up Study (Harvard School of Public Health). In the Nurses’ Health Study, 72,921 participants were followed from June 1984 to June 2008. In the Health Professionals Follow-Up Study, 39,976 participants were followed from June 1986 to June 2008.
The researchers reported 25,480 incident skin cancer cases. Of those, 22,786 were BCC, 1,953 were SCC, and 741 were melanoma.
Song and colleagues reported that women who consumed more than three cups of coffee per day had a 20 percent reduction in risk for BCC, and men who consumed more than three cups per day had a nine percent risk reduction compared with people who consumed less than one cup per month.
The amount of coffee consumption was inversely associated with BCC risk. Those in the highest quintile had the lowest risk, with an 18 percent reduction for women and a 13 percent reduction for men.
Song and colleagues were surprised by the inverse connection in BCC cases only. Animal studies have suggested an association between coffee intake and skin cancer risk, but epidemiologic studies have not conclusively shown the same results, they said.
“Mouse studies have shown that oral or topical caffeine promotes elimination of UV-damaged keratinocytes via apoptosis (programmed cell death) and markedly reduces subsequent SCC development,” Song said. “However, in our cohort analysis, we did not find any inverse association between coffee consumption and the risk for SCC.”
Song said that additional studies specifically addressing the association between coffee consumption and BCC and the mechanism behind this association are warranted.
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Physical fitness could have a positive effect on eye health
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New study links active lifestyle to reduced risk of glaucoma
Physical activity may be what the doctor orders to help patients reduce their risk of developing glaucoma. According to a recently published scientific paper, higher levels of physical exercise appear to have a long-term beneficial impact on low ocular perfusion pressure (OPP), an important risk factor for glaucoma.
Published in the Investigative Ophthalmology & Visual Science journal (Physical Activity and Ocular Perfusion Pressure: The EPIC-Norfolk Eye Study), this study examined the relationship between physical activity and current OPP in 5,650 men and women aged 48 to 90 who live in the U.K. and were part of initial cohort from 1993 - 1997.
Using a detailed self-administered health and lifestyle questionnaire, participants were assessed for combined physical activity at work and leisure. From 2006 to 2010, study participants were examined for eye pressure -- medically termed intraocular pressure (IOP )-- and systolic and diastolic blood pressure measurements. The results showed that moderate physical exercise performed approximately 15 years previously is associated with a 25% reduced risk of low OPP.
"It appears that OPP is largely determined by cardiovascular fitness," said author Paul J. Foster, MD PhD, FRCS(Ed), of the University College London Institute of Ophthalmology. "We cannot comment on the cause, but there is certainly an association between a sedentary lifestyle and factors which increase glaucoma risk."
While there have been a large number of studies that have examined the effect of physical activity on intraocular pressure (IOP) and on blood pressure -- the two components of OPP -- this is the first time the relationship between physical activity and OPP has been investigated, according to the authors.
"Before now, the only modifiable risk factor for glaucoma was IOP, altered by medication, laser or surgery," said Foster. "We believe our study points toward a new way of reducing glaucoma risk, through maintaining an active lifestyle. This is a way that people can participate in altering their risk of glaucoma and many other serious health problems."
New study links active lifestyle to reduced risk of glaucoma
Physical activity may be what the doctor orders to help patients reduce their risk of developing glaucoma. According to a recently published scientific paper, higher levels of physical exercise appear to have a long-term beneficial impact on low ocular perfusion pressure (OPP), an important risk factor for glaucoma.
Published in the Investigative Ophthalmology & Visual Science journal (Physical Activity and Ocular Perfusion Pressure: The EPIC-Norfolk Eye Study), this study examined the relationship between physical activity and current OPP in 5,650 men and women aged 48 to 90 who live in the U.K. and were part of initial cohort from 1993 - 1997.
Using a detailed self-administered health and lifestyle questionnaire, participants were assessed for combined physical activity at work and leisure. From 2006 to 2010, study participants were examined for eye pressure -- medically termed intraocular pressure (IOP )-- and systolic and diastolic blood pressure measurements. The results showed that moderate physical exercise performed approximately 15 years previously is associated with a 25% reduced risk of low OPP.
"It appears that OPP is largely determined by cardiovascular fitness," said author Paul J. Foster, MD PhD, FRCS(Ed), of the University College London Institute of Ophthalmology. "We cannot comment on the cause, but there is certainly an association between a sedentary lifestyle and factors which increase glaucoma risk."
While there have been a large number of studies that have examined the effect of physical activity on intraocular pressure (IOP) and on blood pressure -- the two components of OPP -- this is the first time the relationship between physical activity and OPP has been investigated, according to the authors.
"Before now, the only modifiable risk factor for glaucoma was IOP, altered by medication, laser or surgery," said Foster. "We believe our study points toward a new way of reducing glaucoma risk, through maintaining an active lifestyle. This is a way that people can participate in altering their risk of glaucoma and many other serious health problems."
Friday, October 21, 2011
Biggest ever study shows no link between mobile phone use and tumors
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There is no link between long-term use of mobile phones and tumours of the brain or central nervous system, finds new research published on bmj.com today.
In what is described as the largest study on the subject to date, Danish researchers found no evidence that the risk of brain tumours was raised among 358,403 mobile phone subscribers over an 18-year period.
The number of people using mobile phones is constantly rising with more than five billion subscriptions worldwide in 2010. This has led to concerns about potential adverse health effects, particularly tumours of the central nervous system.
Previous studies on a possible link between phone use and tumours have been inconclusive particularly on long-term use of mobile phones. Some of this earlier work took the form of case control studies involving small numbers of long-term users and were shown to be prone to error and bias. The International Agency for Research on Cancer (IARC) recently classified radio frequency electromagnetic fields, as emitted by mobile phones, as possibly carcinogenic to humans.
The only cohort study investigating mobile phone use and cancer to date is a Danish nationwide study comparing cancer risk of all 420,095 Danish mobile phone subscribers from 1982 until 1995, with the corresponding risk in the rest of the adult population with follow-up to 1996 and then 2002. This study found no evidence of any increased risk of brain or nervous system tumours or any cancer among mobile phone subscribers.
So researchers, led by the Institute of Cancer Epidemiology in Copenhagen, continued this study up to 2007.
They studied data on the whole Danish population aged 30 and over and born in Denmark after 1925, subdivided into subscribers and non-subscribers of mobile phones before 1995. Information was gathered from the Danish phone network operators and from the Danish Cancer Register.
Overall, 10,729 central nervous system tumours occurred in the study period 1990-2007.
When the figures were restricted to people with the longest mobile phone use – 13 years or more – cancer rates were almost the same in both long-term users and non-subscribers of mobile phones.
The researchers say they observed no overall increased risk for tumours of the central nervous system or for all cancers combined in mobile phone users.
They conclude: "The extended follow-up allowed us to investigate effects in people who had used mobile phones for 10 years or more, and this long-term use was not associated with higher risks of cancer.
"However, as a small to moderate increase in risk for subgroups of heavy users or after even longer induction periods than 10-15 years cannot be ruled out, further studies with large study populations, where the potential for misclassification of exposure and selection bias is minimised, are warranted."
In an accompanying editorial, Professors Anders Ahlbom and Maria Feychting at the Karolinska Institutet in Sweden say this new evidence is reassuring, but continued monitoring of health registers and prospective cohorts is still warranted.
There is no link between long-term use of mobile phones and tumours of the brain or central nervous system, finds new research published on bmj.com today.
In what is described as the largest study on the subject to date, Danish researchers found no evidence that the risk of brain tumours was raised among 358,403 mobile phone subscribers over an 18-year period.
The number of people using mobile phones is constantly rising with more than five billion subscriptions worldwide in 2010. This has led to concerns about potential adverse health effects, particularly tumours of the central nervous system.
Previous studies on a possible link between phone use and tumours have been inconclusive particularly on long-term use of mobile phones. Some of this earlier work took the form of case control studies involving small numbers of long-term users and were shown to be prone to error and bias. The International Agency for Research on Cancer (IARC) recently classified radio frequency electromagnetic fields, as emitted by mobile phones, as possibly carcinogenic to humans.
The only cohort study investigating mobile phone use and cancer to date is a Danish nationwide study comparing cancer risk of all 420,095 Danish mobile phone subscribers from 1982 until 1995, with the corresponding risk in the rest of the adult population with follow-up to 1996 and then 2002. This study found no evidence of any increased risk of brain or nervous system tumours or any cancer among mobile phone subscribers.
So researchers, led by the Institute of Cancer Epidemiology in Copenhagen, continued this study up to 2007.
They studied data on the whole Danish population aged 30 and over and born in Denmark after 1925, subdivided into subscribers and non-subscribers of mobile phones before 1995. Information was gathered from the Danish phone network operators and from the Danish Cancer Register.
Overall, 10,729 central nervous system tumours occurred in the study period 1990-2007.
When the figures were restricted to people with the longest mobile phone use – 13 years or more – cancer rates were almost the same in both long-term users and non-subscribers of mobile phones.
The researchers say they observed no overall increased risk for tumours of the central nervous system or for all cancers combined in mobile phone users.
They conclude: "The extended follow-up allowed us to investigate effects in people who had used mobile phones for 10 years or more, and this long-term use was not associated with higher risks of cancer.
"However, as a small to moderate increase in risk for subgroups of heavy users or after even longer induction periods than 10-15 years cannot be ruled out, further studies with large study populations, where the potential for misclassification of exposure and selection bias is minimised, are warranted."
In an accompanying editorial, Professors Anders Ahlbom and Maria Feychting at the Karolinska Institutet in Sweden say this new evidence is reassuring, but continued monitoring of health registers and prospective cohorts is still warranted.
Light drinking = significant decrease in cancer risk
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A paper from the National Institutes of Health in the United States has evaluated the separate and combined effects of the frequency of alcohol consumption and the average quantity of alcohol drunk per occasion and how that relates to mortality risk from individual cancers as well as all cancers. The analysis is based on repeated administrations of the National Health Interview Survey in the US, assessing more than 300,000 subjects who suffered over 8,000 deaths from cancer. The research reports on total cancer deaths and deaths from lung, colorectal, prostate, and breast cancers.
The overall message of this analysis is that light to moderate alcohol intake does not appear to increase the risk of all-site cancer (and light drinking was shown in this study to be associated with a significant decrease in risk). Similarly, light to moderate consumption was not associated with site-specific cancers of the lung, colorectum, breast, or prostate.
As quantity consumed increased from 1 drink on drinking days to 3 or more drinks on drinking days (US drinks are 14g), risk of all-site cancer mortality increased by 22% among all participants. For total alcohol consumption (frequency x quantity), the data indicate a significant reduction in the risk of all-site cancers (RR=0.87, CI 0.80-0.94). Moderate drinking consistently shows no effect in the analysis, and only heavier drinking was associated with an increase in all-site cancer risk. For site-specific cancers, an increase in risk of lung cancer was seen for heavier drinkers, with a tendency for less cancer among light drinkers. There was no evidence of an effect of total alcohol consumption on colorectal, prostate, or breast cancer.
The authors excluded non-drinkers in a second analysis in which they used categories of usual daily quantity and of frequency of consumption in an attempt to investigate their separate effects. For all-site cancer and for lung cancer, these results again show an increase in risk only for drinkers reporting greater amounts of alcohol. The data also show an increase in cancer risk from more frequent drinking among women but not among men. For colorectal, prostate, and breast cancer, there is no clear pattern of an increase in risk from quantity of alcohol consumed. For frequency of drinking, again there is a suggestion of an increase in mortality risk with more frequent drinking, although the trends are not statistically significant.
Heavier drinking (three drinks or more per occasion) is known to be associated with a large number of adverse health effects, including certain cancers, as was shown in this study. When considering cancer, alcohol consumption should not be considered in isolation, but in conjunction with, other lifestyle behaviours (especially smoking when considering lung cancer). We agree with the authors that both quantity and frequency of consumption need to be considered when evaluating the relation of alcohol to cancer; further, beverage-specific effects need to be further evaluated.
A paper from the National Institutes of Health in the United States has evaluated the separate and combined effects of the frequency of alcohol consumption and the average quantity of alcohol drunk per occasion and how that relates to mortality risk from individual cancers as well as all cancers. The analysis is based on repeated administrations of the National Health Interview Survey in the US, assessing more than 300,000 subjects who suffered over 8,000 deaths from cancer. The research reports on total cancer deaths and deaths from lung, colorectal, prostate, and breast cancers.
The overall message of this analysis is that light to moderate alcohol intake does not appear to increase the risk of all-site cancer (and light drinking was shown in this study to be associated with a significant decrease in risk). Similarly, light to moderate consumption was not associated with site-specific cancers of the lung, colorectum, breast, or prostate.
As quantity consumed increased from 1 drink on drinking days to 3 or more drinks on drinking days (US drinks are 14g), risk of all-site cancer mortality increased by 22% among all participants. For total alcohol consumption (frequency x quantity), the data indicate a significant reduction in the risk of all-site cancers (RR=0.87, CI 0.80-0.94). Moderate drinking consistently shows no effect in the analysis, and only heavier drinking was associated with an increase in all-site cancer risk. For site-specific cancers, an increase in risk of lung cancer was seen for heavier drinkers, with a tendency for less cancer among light drinkers. There was no evidence of an effect of total alcohol consumption on colorectal, prostate, or breast cancer.
The authors excluded non-drinkers in a second analysis in which they used categories of usual daily quantity and of frequency of consumption in an attempt to investigate their separate effects. For all-site cancer and for lung cancer, these results again show an increase in risk only for drinkers reporting greater amounts of alcohol. The data also show an increase in cancer risk from more frequent drinking among women but not among men. For colorectal, prostate, and breast cancer, there is no clear pattern of an increase in risk from quantity of alcohol consumed. For frequency of drinking, again there is a suggestion of an increase in mortality risk with more frequent drinking, although the trends are not statistically significant.
Heavier drinking (three drinks or more per occasion) is known to be associated with a large number of adverse health effects, including certain cancers, as was shown in this study. When considering cancer, alcohol consumption should not be considered in isolation, but in conjunction with, other lifestyle behaviours (especially smoking when considering lung cancer). We agree with the authors that both quantity and frequency of consumption need to be considered when evaluating the relation of alcohol to cancer; further, beverage-specific effects need to be further evaluated.
Soy protein improves lipid profile in healthy individuals
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A new study published online in the European Journal of Clinical Nutrition shows that soy protein compared to dairy milk protein supplementation improves the lipid profile in healthy individuals. This study investigated the effect of soy and milk protein supplementation on lipids compared with carbohydrate among healthy adults. Numerous research studies have demonstrated that soy protein reduces LDL ("the bad") cholesterol and increases HDL ("the good") cholesterol, supporting the soy protein heart health and cholesterol-lowering claim that is approved in 12 countries around the globe.
"Coronary heart disease (CHD) is a major health epidemic, as the No. 1 killer of women and men globally. Research has shown that lowering blood lipids reduces the risk of coronary heart disease and stroke," said Elaine Krul, Ph.D., nutrition discovery lead at Solae. "The results of this study reveal that soy protein supplementation intake can help lower blood lipids, thus helping to reduce the risk of CHD in healthy individuals."
In this study, total cholesterol reduction as well as the total/HDL cholesterol ratio reduction was statistically significant with soy protein supplementation compared with carbohydrate. Compared with milk protein, soy protein supplementation significantly increased HDL and significantly reduced total/HDL cholesterol ratio as well as lowered LDL cholesterol.
The National Cholesterol Education Program emphasizes the importance of therapeutic lifestyle changes for primary prevention of high cholesterol. This includes dietary modification, body weight reduction and increased physical activity. There is increasing evidence that consumption of soy protein in place of animal protein lowers blood cholesterol levels and may provide other cardiovascular benefits. The results of this study are intriguing in that these risk reduction benefits were observed in healthy (non-hypercholesterolemic) individuals.
"It's the simple lifestyle changes, such as including soy protein in your diet, that can often have a positive impact on your health," said Krul. "Research continues to demonstrate that soy protein can help lower LDL cholesterol, an important biomarker for coronary heart disease."
This study was a randomized, controlled trial that included 352 U.S. healthy adults. It was conducted from September 2003 to April 2008. Participants in the study were assigned to 40 g/day supplementation of soy protein, milk protein or complex carbohydrate for 8 weeks in random order. Solae provided the supplements used in this study. For more information on the study, the following is a link to the abstract:
A new study published online in the European Journal of Clinical Nutrition shows that soy protein compared to dairy milk protein supplementation improves the lipid profile in healthy individuals. This study investigated the effect of soy and milk protein supplementation on lipids compared with carbohydrate among healthy adults. Numerous research studies have demonstrated that soy protein reduces LDL ("the bad") cholesterol and increases HDL ("the good") cholesterol, supporting the soy protein heart health and cholesterol-lowering claim that is approved in 12 countries around the globe.
"Coronary heart disease (CHD) is a major health epidemic, as the No. 1 killer of women and men globally. Research has shown that lowering blood lipids reduces the risk of coronary heart disease and stroke," said Elaine Krul, Ph.D., nutrition discovery lead at Solae. "The results of this study reveal that soy protein supplementation intake can help lower blood lipids, thus helping to reduce the risk of CHD in healthy individuals."
In this study, total cholesterol reduction as well as the total/HDL cholesterol ratio reduction was statistically significant with soy protein supplementation compared with carbohydrate. Compared with milk protein, soy protein supplementation significantly increased HDL and significantly reduced total/HDL cholesterol ratio as well as lowered LDL cholesterol.
The National Cholesterol Education Program emphasizes the importance of therapeutic lifestyle changes for primary prevention of high cholesterol. This includes dietary modification, body weight reduction and increased physical activity. There is increasing evidence that consumption of soy protein in place of animal protein lowers blood cholesterol levels and may provide other cardiovascular benefits. The results of this study are intriguing in that these risk reduction benefits were observed in healthy (non-hypercholesterolemic) individuals.
"It's the simple lifestyle changes, such as including soy protein in your diet, that can often have a positive impact on your health," said Krul. "Research continues to demonstrate that soy protein can help lower LDL cholesterol, an important biomarker for coronary heart disease."
This study was a randomized, controlled trial that included 352 U.S. healthy adults. It was conducted from September 2003 to April 2008. Participants in the study were assigned to 40 g/day supplementation of soy protein, milk protein or complex carbohydrate for 8 weeks in random order. Solae provided the supplements used in this study. For more information on the study, the following is a link to the abstract:
HIGH TO MODERATE LEVELS OF STRESS LEAD TO HIGHER MORTALITY RATE
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A new study concludes that men who experience persistently moderate or high levels of stressful life events over a number of years have a 50 percent higher mortality rate.
In general, the researchers found only a few protective factors against these higher levels of stress – people who self-reported that they had good health tended to live longer and married men also fared better. Moderate drinkers also lived longer than non-drinkers.
“Being a teetotaler and a smoker were risk factors for mortality,” said Carolyn Aldwin, lead author of the study and a professor of human development and family sciences at Oregon State University. “So perhaps trying to keep your major stress events to a minimum, being married and having a glass of wine every night is the secret to a long life.”
This is the first study to show a direct link between stress trajectories and mortality in an aging population. Unlike previous studies that were conducted in a relatively short term with smaller sample sizes, this study was modified to document major stressors – such as death of a spouse or a putting a parent into a retirement home – that specifically affect middle-aged and older people.
“Most studies look at typical stress events that are geared at younger people, such as graduation, losing a job, having your first child,” Aldwin said. “I modified the stress measure to reflect the kinds of stress that we know impacts us more as we age, and even we were surprised at how strong the correlation between stress trajectories and mortality was.”
Aldwin said that previous studies examined stress only at one time point, while this study documented patterns of stress over a number of years.
The study, out now in the Journal of Aging Research, used longitudinal data surveying almost 1,000 middle-class and working-class men for an 18-year period, from 1985 to 2003. All the men in the study were picked because they had good health when they first signed up to be part of the Boston VA Normative Aging Study in the 1960s.
Those in the low-stress group experienced an average of two or fewer major life events in a year, compared with an average of three for the moderate group and up to six for the high stress group. One of the study’s most surprising findings was that the mortality risk was similar for the moderate versus high stress group.
“It seems there is a threshold and perhaps with anything more than two major life events a year and people just max out,” Aldwin said. “We were surprised the effect was not linear and that the moderate group had a similar risk of death to the high-risk group.”
While this study looked specifically at major life events and stress trajectories, Aldwin said the research group will next explore chronic daily stress as well as coping strategies.
“People are hardy, and they can deal with a few major stress events each year,” Aldwin said. “But our research suggests that long-term, even moderate stress can have lethal effects.”
A new study concludes that men who experience persistently moderate or high levels of stressful life events over a number of years have a 50 percent higher mortality rate.
In general, the researchers found only a few protective factors against these higher levels of stress – people who self-reported that they had good health tended to live longer and married men also fared better. Moderate drinkers also lived longer than non-drinkers.
“Being a teetotaler and a smoker were risk factors for mortality,” said Carolyn Aldwin, lead author of the study and a professor of human development and family sciences at Oregon State University. “So perhaps trying to keep your major stress events to a minimum, being married and having a glass of wine every night is the secret to a long life.”
This is the first study to show a direct link between stress trajectories and mortality in an aging population. Unlike previous studies that were conducted in a relatively short term with smaller sample sizes, this study was modified to document major stressors – such as death of a spouse or a putting a parent into a retirement home – that specifically affect middle-aged and older people.
“Most studies look at typical stress events that are geared at younger people, such as graduation, losing a job, having your first child,” Aldwin said. “I modified the stress measure to reflect the kinds of stress that we know impacts us more as we age, and even we were surprised at how strong the correlation between stress trajectories and mortality was.”
Aldwin said that previous studies examined stress only at one time point, while this study documented patterns of stress over a number of years.
The study, out now in the Journal of Aging Research, used longitudinal data surveying almost 1,000 middle-class and working-class men for an 18-year period, from 1985 to 2003. All the men in the study were picked because they had good health when they first signed up to be part of the Boston VA Normative Aging Study in the 1960s.
Those in the low-stress group experienced an average of two or fewer major life events in a year, compared with an average of three for the moderate group and up to six for the high stress group. One of the study’s most surprising findings was that the mortality risk was similar for the moderate versus high stress group.
“It seems there is a threshold and perhaps with anything more than two major life events a year and people just max out,” Aldwin said. “We were surprised the effect was not linear and that the moderate group had a similar risk of death to the high-risk group.”
While this study looked specifically at major life events and stress trajectories, Aldwin said the research group will next explore chronic daily stress as well as coping strategies.
“People are hardy, and they can deal with a few major stress events each year,” Aldwin said. “But our research suggests that long-term, even moderate stress can have lethal effects.”
Early mortality risk reduced up to 40 percent through increased physical activity and sports
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Even though previous studies have been shown the link between regular exercises and improved health the exact dose-response relation remains unclear. Guenther Samitz, researcher in physical activity and public health at the Centre for Sports Sciences and University Sports of the University of Vienna has investigated this relationship with a meta-study representing more than 1.3 million participants. The research project was carried out in collaboration with public health scientists and epidemiologists of the Universities of Bern, Switzerland and Bristol, UK. The results of the study have been published in International Journal of Epidemiology.
One week is 10.080 minutes, already 150 minutes of moderate-intensity physical activity per week protect against chronic diseases and premature death according to the recommendations of the World Health Organisation (WHO). A research group around Guenther Samitz of the Centre for Sports Sciences and University Sports at the University of Vienna investigated that link between increased levels of physical activity of different domains (occupation, daily living, transportation, and leisure) and all-cause mortality. The investigators also assessed to what extent current WHO recommendations for physical activity decrease the risk of premature death in adult populations.
80 studies with 1.3 million study participants
The study was conducted as a systematic review including multiple meta-analyses. Meta-analyses combine the results of individual studies that address a set of predefined research questions. In Public Health and Medicine the evidence from meta-analyses is often used to update or revise recommendations and guidelines for prevention and therapy.
The researchers identified about 7,000 potentially relevant reports, of which a total of 80 cohort studies with more than 1.3 million study participants from Europe, Canada, United States, and Asia fulfilled the strict inclusion criteria. At study onset participants had to be free of cardiovascular disease, cancer and other chronic conditions. Study participants were followed up by a median of 11 years. 'The results of the included studies were combined and controlled for other potential influential factors, e.g. cigarette smoking, alcohol uptake, body mass index, blood pressure, nutrition, education and social factors,' explained Guenther Samitz.
Women benefit more than men
In Europe only about one third of the adult population meets the minimum WHO recommendation for physical activity. Higher levels of physical activity were associated with reduced all-cause mortality, regardless whether in job, daily living, leisure or active transportation. However, the association was higher for leisure time physical activity and activities of daily living, and mortality reductions were more pronounced in women when compared with men. Women and older persons even had a survival benefit when engaging in regular light- to moderate-intensity activities of daily living, e.g. domestic work, gardening, walking or bicycling to the shopping mall. It is unclear why the survival benefit from physical activity across all domains was consistently higher for women. The study authors suspect that changes in female hormone levels, in oestrogen metabolism and body fat distribution could partly be responsible for this difference.
Some physical activity is good, more is better
In a second step the investigators quantified the mortality benefit in dependence upon the physical activity dose per week. For light- to moderate intensity activities of daily living, e.g. housework, gardening, stair climbing, walking and bicycling for transportation, an increase of one hour per week compared to no physical activity was associated with a reduction in mortality of four percent. Dr. Samitz said that with moderate-intensity leisure activities (e.g. Nordic walking, hiking, social dance) the risk reduction increased to six percent, and with vigorous-intensity aerobic activity or sports (e.g. jogging, bicycling (>10 miles per hour), tennis, ball sport), the reduction in all-cause mortality was even nine percent per one hour increment per week.
Meeting the WHO´s recommended level of 150 minutes per week of moderate physical activity of daily life or during leisure was associated with a reduction in mortality risk by ten percent. For vigorous exercise and sports the reduction in mortality risk was more than twofold higher (22 %).
300 minutes (five hours) per week, this activity level is recommended for extended health benefits, were associated with a reduction in mortality risk by 19% and 39% for moderate-intensity activities of daily living, and vigorous-intensity aerobic activity and sports, respectively. But even for lower levels than recommended by the WHO the researchers observed a significant survival benefit.
'Any physical activity is better than none and even activities of daily life are associated with a survival benefit, but more and vigorous-intensity physical activity are associated with a larger reduction in all-cause mortality', summarizes Samitz and he recommends: 'Nonetheless, sedentary adults should start with moderate-intensity physical activities and slowly increase weekly dose and intensity, because in javascript:void(0)sedentary adults vigorous-intensity physical activity is associated with increased risk of musculoskeletal injuries and adverse cardiac events.'
Even though previous studies have been shown the link between regular exercises and improved health the exact dose-response relation remains unclear. Guenther Samitz, researcher in physical activity and public health at the Centre for Sports Sciences and University Sports of the University of Vienna has investigated this relationship with a meta-study representing more than 1.3 million participants. The research project was carried out in collaboration with public health scientists and epidemiologists of the Universities of Bern, Switzerland and Bristol, UK. The results of the study have been published in International Journal of Epidemiology.
One week is 10.080 minutes, already 150 minutes of moderate-intensity physical activity per week protect against chronic diseases and premature death according to the recommendations of the World Health Organisation (WHO). A research group around Guenther Samitz of the Centre for Sports Sciences and University Sports at the University of Vienna investigated that link between increased levels of physical activity of different domains (occupation, daily living, transportation, and leisure) and all-cause mortality. The investigators also assessed to what extent current WHO recommendations for physical activity decrease the risk of premature death in adult populations.
80 studies with 1.3 million study participants
The study was conducted as a systematic review including multiple meta-analyses. Meta-analyses combine the results of individual studies that address a set of predefined research questions. In Public Health and Medicine the evidence from meta-analyses is often used to update or revise recommendations and guidelines for prevention and therapy.
The researchers identified about 7,000 potentially relevant reports, of which a total of 80 cohort studies with more than 1.3 million study participants from Europe, Canada, United States, and Asia fulfilled the strict inclusion criteria. At study onset participants had to be free of cardiovascular disease, cancer and other chronic conditions. Study participants were followed up by a median of 11 years. 'The results of the included studies were combined and controlled for other potential influential factors, e.g. cigarette smoking, alcohol uptake, body mass index, blood pressure, nutrition, education and social factors,' explained Guenther Samitz.
Women benefit more than men
In Europe only about one third of the adult population meets the minimum WHO recommendation for physical activity. Higher levels of physical activity were associated with reduced all-cause mortality, regardless whether in job, daily living, leisure or active transportation. However, the association was higher for leisure time physical activity and activities of daily living, and mortality reductions were more pronounced in women when compared with men. Women and older persons even had a survival benefit when engaging in regular light- to moderate-intensity activities of daily living, e.g. domestic work, gardening, walking or bicycling to the shopping mall. It is unclear why the survival benefit from physical activity across all domains was consistently higher for women. The study authors suspect that changes in female hormone levels, in oestrogen metabolism and body fat distribution could partly be responsible for this difference.
Some physical activity is good, more is better
In a second step the investigators quantified the mortality benefit in dependence upon the physical activity dose per week. For light- to moderate intensity activities of daily living, e.g. housework, gardening, stair climbing, walking and bicycling for transportation, an increase of one hour per week compared to no physical activity was associated with a reduction in mortality of four percent. Dr. Samitz said that with moderate-intensity leisure activities (e.g. Nordic walking, hiking, social dance) the risk reduction increased to six percent, and with vigorous-intensity aerobic activity or sports (e.g. jogging, bicycling (>10 miles per hour), tennis, ball sport), the reduction in all-cause mortality was even nine percent per one hour increment per week.
Meeting the WHO´s recommended level of 150 minutes per week of moderate physical activity of daily life or during leisure was associated with a reduction in mortality risk by ten percent. For vigorous exercise and sports the reduction in mortality risk was more than twofold higher (22 %).
300 minutes (five hours) per week, this activity level is recommended for extended health benefits, were associated with a reduction in mortality risk by 19% and 39% for moderate-intensity activities of daily living, and vigorous-intensity aerobic activity and sports, respectively. But even for lower levels than recommended by the WHO the researchers observed a significant survival benefit.
'Any physical activity is better than none and even activities of daily life are associated with a survival benefit, but more and vigorous-intensity physical activity are associated with a larger reduction in all-cause mortality', summarizes Samitz and he recommends: 'Nonetheless, sedentary adults should start with moderate-intensity physical activities and slowly increase weekly dose and intensity, because in javascript:void(0)sedentary adults vigorous-intensity physical activity is associated with increased risk of musculoskeletal injuries and adverse cardiac events.'
Tuesday, October 18, 2011
Omega-3 fatty acids shown to prevent or slow progression of osteoarthritis
Ω
New research has shown for the first time that omega-3 in fish oil could "substantially and significantly" reduce the signs and symptoms of osteoarthritis.
According to the University of Bristol study, funded by Arthritis Research UK and published in the journal Osteoarthritis and Cartilage, omega-3-rich diets fed to guinea pigs, which naturally develop osteoarthritis, reduced disease by 50 per cent compared to a standard diet.
The research is a major step forward in showing that omega-3 fatty acids, either sourced from fish oil or flax oil, may help to slow down the progression of osteoarthritis, or even prevent it occurring, confirming anecdotal reports and "old wives' tales" about the benefits of fish oil for joint health.
Lead researcher Dr John Tarlton, from the Matrix Biology Research group at the University of Bristol's School of Veterinary Sciences, said classic early signs of the condition, such as the degradation of collagen in cartilage and the loss of molecules that give it shock-absorbing properties, were both reduced with omega-3.
"Furthermore, there was strong evidence that omega-3 influences the biochemistry of the disease, and therefore not only helps prevent disease, but also slows its progression, potentially controlling established osteoarthritis," he said.
Dr Tarlton added: "The only way of being certain that the effects of omega-3 are as applicable to humans as demonstrated in guinea pigs is to apply omega-3 to humans. However, osteoarthritis in guinea pigs is perhaps the most appropriate model for spontaneous, naturally occurring osteoarthritis, and all of the evidence supports the use of omega-3 in human disease."
Medical research director of Arthritis Research UK, Professor Alan Silman, said: "The possibility that omega-3 fatty acids could prevent osteoarthritis from developing has been a tantalising one. Some limited, previous research in dogs has suggested that we were a long way away from understanding the potential use in humans. However, this current research in guinea pigs is exciting as it brings us closer to understanding how omega-3 might fundamentally interfere with the osteoarthritis process, and that it could potentially be taken as a treatment."
On the back of the results of his study, Dr Tarlton said that following government guidelines on dietary intake of omega-3 fatty acids could be effective in reducing the burden of osteoarthritis. Fish oil is far more effective than the flax oil based supplement, but for vegetarians flax oil remains a viable alternative.
"Most diets in the developed world are lacking in omega-3, with modern diets having up to 30 times too much omega-6 and too little omega-3. Taking omega-3 will help redress this imbalance and may positively contribute to a range of other health problems such as heart disease and colitis."
Further studies are needed to determine the influence of omega-3 fatty acids on established disease in guinea pigs, and to confirm the effects in human osteoarthritis, said Dr Tarlton.
Osteoarthritis affects around eight million people in the UK, and is caused when the cartilage at the ends of bones wears away and the underlying bone thickens, leading to stiff, painful joints. Currently, there is no effective treatment to slow down disease progression, and treatment is limited to pain relief and ultimately joint replacement.
New research has shown for the first time that omega-3 in fish oil could "substantially and significantly" reduce the signs and symptoms of osteoarthritis.
According to the University of Bristol study, funded by Arthritis Research UK and published in the journal Osteoarthritis and Cartilage, omega-3-rich diets fed to guinea pigs, which naturally develop osteoarthritis, reduced disease by 50 per cent compared to a standard diet.
The research is a major step forward in showing that omega-3 fatty acids, either sourced from fish oil or flax oil, may help to slow down the progression of osteoarthritis, or even prevent it occurring, confirming anecdotal reports and "old wives' tales" about the benefits of fish oil for joint health.
Lead researcher Dr John Tarlton, from the Matrix Biology Research group at the University of Bristol's School of Veterinary Sciences, said classic early signs of the condition, such as the degradation of collagen in cartilage and the loss of molecules that give it shock-absorbing properties, were both reduced with omega-3.
"Furthermore, there was strong evidence that omega-3 influences the biochemistry of the disease, and therefore not only helps prevent disease, but also slows its progression, potentially controlling established osteoarthritis," he said.
Dr Tarlton added: "The only way of being certain that the effects of omega-3 are as applicable to humans as demonstrated in guinea pigs is to apply omega-3 to humans. However, osteoarthritis in guinea pigs is perhaps the most appropriate model for spontaneous, naturally occurring osteoarthritis, and all of the evidence supports the use of omega-3 in human disease."
Medical research director of Arthritis Research UK, Professor Alan Silman, said: "The possibility that omega-3 fatty acids could prevent osteoarthritis from developing has been a tantalising one. Some limited, previous research in dogs has suggested that we were a long way away from understanding the potential use in humans. However, this current research in guinea pigs is exciting as it brings us closer to understanding how omega-3 might fundamentally interfere with the osteoarthritis process, and that it could potentially be taken as a treatment."
On the back of the results of his study, Dr Tarlton said that following government guidelines on dietary intake of omega-3 fatty acids could be effective in reducing the burden of osteoarthritis. Fish oil is far more effective than the flax oil based supplement, but for vegetarians flax oil remains a viable alternative.
"Most diets in the developed world are lacking in omega-3, with modern diets having up to 30 times too much omega-6 and too little omega-3. Taking omega-3 will help redress this imbalance and may positively contribute to a range of other health problems such as heart disease and colitis."
Further studies are needed to determine the influence of omega-3 fatty acids on established disease in guinea pigs, and to confirm the effects in human osteoarthritis, said Dr Tarlton.
Osteoarthritis affects around eight million people in the UK, and is caused when the cartilage at the ends of bones wears away and the underlying bone thickens, leading to stiff, painful joints. Currently, there is no effective treatment to slow down disease progression, and treatment is limited to pain relief and ultimately joint replacement.
Thursday, October 13, 2011
Eating green veggies improves immune defenses
Ω
Researchers reporting online in the journal Cell, a Cell Press publication, on October 13th have found another good reason to eat your green vegetables, although it may or may not win any arguments with kids at the dinner table.
It turns out that green vegetables -- from bok choy to broccoli -- are the source of a chemical signal that is important to a fully functioning immune system. They do this by ensuring that immune cells in the gut and the skin known as intra-epithelial lymphocytes (IELs) function properly.
"It is still surprising to me," said Marc Veldhoen of The Babraham Institute in Cambridge. "I would have expected cells at the surface would play some role in the interaction with the outside world, but such a clear cut interaction with the diet was unexpected. After feeding otherwise healthy mice a vegetable-poor diet for two to three weeks, I was amazed to see 70 to 80 percent of these protective cells disappeared."
Those protective IELs exist as a network beneath the barrier of epithelial cells covering inner and outer body surfaces, where they are important as a first line of defense and in wound repair. Veldhoen's team now finds that the numbers of IELs depend on levels of a cell-surface protein called the aryl hydrocarbon receptor (AhR), which can be regulated by dietary ingredients found primarily in cruciferous vegetables. Mice lacking this receptor lose control over the microbes living on the intestinal surface, both in terms of their numbers and composition.
Earlier studies suggested that breakdown of cruciferous vegetables can yield a compound that can be converted into a molecule that triggers AhRs. The new work finds that mice fed a synthetic diet lacking this key compound experience a significant reduction in AhR activity and lose IELs. With reduced numbers of these key immune cells, animals showed lower levels of antimicrobial proteins, heightened immune activation and greater susceptibility to injury. When the researchers intentionally damaged the intestinal surface in animals that didn't have normal AhR activity, the mice were not as "quick to repair" that damage.
As an immunologist, Veldhoen says he hopes the findings will generate interest in the medical community, noting that some of the characteristics observed in the mice are consistent with those seen in patients with inflammatory bowel disease.
"It's tempting to extrapolate to humans," he said. "But there are many other factors that might play a role."
For the rest of us, he says, "it's already a good idea to eat your greens." Still, the results offer a molecular basis for the importance of cruciferous vegetable-derived phyto-nutrients as part of a healthy diet.
Researchers reporting online in the journal Cell, a Cell Press publication, on October 13th have found another good reason to eat your green vegetables, although it may or may not win any arguments with kids at the dinner table.
It turns out that green vegetables -- from bok choy to broccoli -- are the source of a chemical signal that is important to a fully functioning immune system. They do this by ensuring that immune cells in the gut and the skin known as intra-epithelial lymphocytes (IELs) function properly.
"It is still surprising to me," said Marc Veldhoen of The Babraham Institute in Cambridge. "I would have expected cells at the surface would play some role in the interaction with the outside world, but such a clear cut interaction with the diet was unexpected. After feeding otherwise healthy mice a vegetable-poor diet for two to three weeks, I was amazed to see 70 to 80 percent of these protective cells disappeared."
Those protective IELs exist as a network beneath the barrier of epithelial cells covering inner and outer body surfaces, where they are important as a first line of defense and in wound repair. Veldhoen's team now finds that the numbers of IELs depend on levels of a cell-surface protein called the aryl hydrocarbon receptor (AhR), which can be regulated by dietary ingredients found primarily in cruciferous vegetables. Mice lacking this receptor lose control over the microbes living on the intestinal surface, both in terms of their numbers and composition.
Earlier studies suggested that breakdown of cruciferous vegetables can yield a compound that can be converted into a molecule that triggers AhRs. The new work finds that mice fed a synthetic diet lacking this key compound experience a significant reduction in AhR activity and lose IELs. With reduced numbers of these key immune cells, animals showed lower levels of antimicrobial proteins, heightened immune activation and greater susceptibility to injury. When the researchers intentionally damaged the intestinal surface in animals that didn't have normal AhR activity, the mice were not as "quick to repair" that damage.
As an immunologist, Veldhoen says he hopes the findings will generate interest in the medical community, noting that some of the characteristics observed in the mice are consistent with those seen in patients with inflammatory bowel disease.
"It's tempting to extrapolate to humans," he said. "But there are many other factors that might play a role."
For the rest of us, he says, "it's already a good idea to eat your greens." Still, the results offer a molecular basis for the importance of cruciferous vegetable-derived phyto-nutrients as part of a healthy diet.
Increased prostate cancer risk from vitamin E supplements
Ω
Men who took 400 international units (I.U.) of vitamin E daily had more prostate cancers compared to men who took a placebo, according to an updated review of data from the Selenium and Vitamin E Cancer Prevention Trial (SELECT). The findings showed that, per 1,000 men, there were 76 prostate cancers in men who took only vitamin E supplements, vs. 65 in men on placebo over a seven-year period, or 11 more cases of prostate cancer per 1,000 men. This represents a 17 percent increase in prostate cancers relative to those who took a placebo. This difference was statistically significant and therefore is not likely due to chance. The results of this update appeared Oct. 12, 2011, in the Journal of the American Medical Association.
SWOG, an international network of research institutions, carried out SELECT at more than 400 clinical sites in the United States, Puerto Rico, and Canada. SELECT was funded by the National Cancer Institute (NCI) and other institutes that comprise the National Institutes of Health.
The crystalline structure of Vitamin E“Based on these results and the results of large cardiovascular studies using vitamin E, there is no reason for men in the general population to take the dose of vitamin E used in SELECT as the supplements have shown no benefit and some very real risks,” said Eric Klein, M.D., a study co-chair for SELECT, and a physician at the Cleveland Clinic. “For now, men who were part of SELECT should continue to see their primary care physician or urologist and bring these results to their attention for further consideration.”
The SELECT study began in 2001 and included over 35,000 men. It was started because earlier research had suggested that selenium or vitamin E might reduce the risk of developing prostate cancer. However, based on an independent safety monitoring review in autumn 2008, participants were told to stop taking their study supplements because it had become clear that the trial would never produce the 25 percent reduction in prostate cancer the study was designed to show with the use of these supplements. In 2010, the study sites were closed and over half of the participants consented to have their health monitored via mail questionnaires. Now, because of this latest finding, researchers are encouraging all participants to consider taking part in long-term study follow-up so investigators can continue to track outcomes.
SELECT was undertaken to substantiate earlier, separate findings from studies in which prostate cancer risk was not the primary outcome. A 1998 study of male smokers in Finland who took 50 I.U. of vitamin E daily to prevent lung cancer, showed 32 percent fewer prostate cancers in men who took the supplement. A 1996 study of men and women with a history of skin cancer who took selenium for prevention of disease recurrence showed that men who took the supplement had 52 percent fewer prostate cancers than men who did not take the supplement.
Based on these and other findings, men were recruited to participate in SELECT. They were randomly assigned to take one of four sets of supplements or placebos, with more than 8,000 men in each group. One group took both selenium and vitamin E; one took selenium and a placebo that looked similar to vitamin E; one took vitamin E and a placebo that looked similar to selenium; and the final group received placebos of both supplements. Men who took selenium alone or vitamin E and selenium together were also more likely to develop prostate cancer than men who took a placebo, but those increases were small and possibly due to chance.
“SELECT has definitively shown a lack of benefit from vitamin E and selenium supplements in the prevention of prostate cancer and has shown there is the potential for harm,” said Lori Minasian, M.D., study co-author and acting director of NCI’s Division of Cancer Prevention. “Nevertheless, this type of research has been critically important to understanding the potential benefits and risks from supplements.”
SELECT researchers are now measuring the amount of vitamin E, selenium, and other nutrients in the blood of participants when they joined the trial, to see if the effect of the supplements depended upon this baseline level of micronutrient. Other researchers are looking at single nucleotide polymorphisms, which are DNA changes known as SNPs, to see if a change in one or more genes could affect cancer risk or perhaps increase a man’s risk of developing prostate cancer while taking vitamin E.
The participant samples come from the study biorepository of blood and toe nail clippings which, when coupled with the extensive clinical information on participants, is a vital resource for further study. “SWOG is soliciting proposals from researchers nationwide to use the SELECT biorepository to help answer the biological question of why vitamin E increased risk instead of decreasing it,” said Laurence Baker, D.O., study co-author and chairman of SWOG. “There are many more questions raised by these study results than we have answers for, and thus the need for further investigation.”
Except for skin cancer, prostate cancer is the most common type of cancer in men in the United States. The current lifetime risk of prostate cancer for American men is 16 percent. In 2011, there will be an estimated 240,890 new cases of prostate cancer and 33,720 deaths from this disease in the United States.
Men who took 400 international units (I.U.) of vitamin E daily had more prostate cancers compared to men who took a placebo, according to an updated review of data from the Selenium and Vitamin E Cancer Prevention Trial (SELECT). The findings showed that, per 1,000 men, there were 76 prostate cancers in men who took only vitamin E supplements, vs. 65 in men on placebo over a seven-year period, or 11 more cases of prostate cancer per 1,000 men. This represents a 17 percent increase in prostate cancers relative to those who took a placebo. This difference was statistically significant and therefore is not likely due to chance. The results of this update appeared Oct. 12, 2011, in the Journal of the American Medical Association.
SWOG, an international network of research institutions, carried out SELECT at more than 400 clinical sites in the United States, Puerto Rico, and Canada. SELECT was funded by the National Cancer Institute (NCI) and other institutes that comprise the National Institutes of Health.
The crystalline structure of Vitamin E“Based on these results and the results of large cardiovascular studies using vitamin E, there is no reason for men in the general population to take the dose of vitamin E used in SELECT as the supplements have shown no benefit and some very real risks,” said Eric Klein, M.D., a study co-chair for SELECT, and a physician at the Cleveland Clinic. “For now, men who were part of SELECT should continue to see their primary care physician or urologist and bring these results to their attention for further consideration.”
The SELECT study began in 2001 and included over 35,000 men. It was started because earlier research had suggested that selenium or vitamin E might reduce the risk of developing prostate cancer. However, based on an independent safety monitoring review in autumn 2008, participants were told to stop taking their study supplements because it had become clear that the trial would never produce the 25 percent reduction in prostate cancer the study was designed to show with the use of these supplements. In 2010, the study sites were closed and over half of the participants consented to have their health monitored via mail questionnaires. Now, because of this latest finding, researchers are encouraging all participants to consider taking part in long-term study follow-up so investigators can continue to track outcomes.
SELECT was undertaken to substantiate earlier, separate findings from studies in which prostate cancer risk was not the primary outcome. A 1998 study of male smokers in Finland who took 50 I.U. of vitamin E daily to prevent lung cancer, showed 32 percent fewer prostate cancers in men who took the supplement. A 1996 study of men and women with a history of skin cancer who took selenium for prevention of disease recurrence showed that men who took the supplement had 52 percent fewer prostate cancers than men who did not take the supplement.
Based on these and other findings, men were recruited to participate in SELECT. They were randomly assigned to take one of four sets of supplements or placebos, with more than 8,000 men in each group. One group took both selenium and vitamin E; one took selenium and a placebo that looked similar to vitamin E; one took vitamin E and a placebo that looked similar to selenium; and the final group received placebos of both supplements. Men who took selenium alone or vitamin E and selenium together were also more likely to develop prostate cancer than men who took a placebo, but those increases were small and possibly due to chance.
“SELECT has definitively shown a lack of benefit from vitamin E and selenium supplements in the prevention of prostate cancer and has shown there is the potential for harm,” said Lori Minasian, M.D., study co-author and acting director of NCI’s Division of Cancer Prevention. “Nevertheless, this type of research has been critically important to understanding the potential benefits and risks from supplements.”
SELECT researchers are now measuring the amount of vitamin E, selenium, and other nutrients in the blood of participants when they joined the trial, to see if the effect of the supplements depended upon this baseline level of micronutrient. Other researchers are looking at single nucleotide polymorphisms, which are DNA changes known as SNPs, to see if a change in one or more genes could affect cancer risk or perhaps increase a man’s risk of developing prostate cancer while taking vitamin E.
The participant samples come from the study biorepository of blood and toe nail clippings which, when coupled with the extensive clinical information on participants, is a vital resource for further study. “SWOG is soliciting proposals from researchers nationwide to use the SELECT biorepository to help answer the biological question of why vitamin E increased risk instead of decreasing it,” said Laurence Baker, D.O., study co-author and chairman of SWOG. “There are many more questions raised by these study results than we have answers for, and thus the need for further investigation.”
Except for skin cancer, prostate cancer is the most common type of cancer in men in the United States. The current lifetime risk of prostate cancer for American men is 16 percent. In 2011, there will be an estimated 240,890 new cases of prostate cancer and 33,720 deaths from this disease in the United States.
Heart Disease: Eating Fruits and Raw Vegetables Can Change the Effect of Your Genes
Ω
A long-held mantra suggests that you can't change your family, the genes they pass on, or the effect of these genes. Now, an international team of scientists, led by researchers at McMaster and McGill universities, is attacking that belief.
The researchers discovered the gene that is the strongest marker for heart disease can actually be modified by generous amounts of fruit and raw vegetables. The results of their study are published in the current issue of the journal PLoS Medicine.
"We know that 9p21 genetic variants increase the risk of heart disease for those that carry it," said Dr. Jamie Engert, joint principal investigator of the study, who is a researcher in cardiovascular diseases at the Research Institute of the McGill University Health Centre (RI-MUHC) and associate member in the Department of Human Genetics at McGill University. "But it was a surprise to find that a healthy diet could significantly weaken its effect."
The research, which represents one of the largest gene-diet interaction studies ever conducted on cardiovascular disease, involved the analysis of more than 27,000 individuals from five ethnicities -- European, South Asian, Chinese, Latin American and Arab -- and the effect that their diets had on the effect of the 9p21 gene. The results suggest that individuals with the high risk genotype who consumed a prudent diet, composed mainly of raw vegetables, fruits and berries, had a similar risk of heart attack to those with the low risk genotype.
"We observed that the effect of a high-risk genotype can be mitigated by consuming a diet high in fruits and vegetables," said Sonia Anand, joint principal investigator of the study, and a researcher at the Population Health Research Institute and a professor of medicine and epidemiology at the Michael G. DeGroote School of Medicine at McMaster University. "Our results support the public health recommendation to consume more than five servings of fruits or vegetables as a way to promote good health."
"Our research suggests there may be an important interplay between genes and diet in cardiovascular disease," says the study's lead author Dr. Ron Do, who conducted this research as part of his PhD at McGill and is now based at the Center for Human Genetics Research at the Massachusetts General Hospital, Boston, Massachusetts. "Future research is necessary to understand the mechanism of this interaction, which will shed light on the underlying metabolic processes that the 9p21 gene is involved in."
A long-held mantra suggests that you can't change your family, the genes they pass on, or the effect of these genes. Now, an international team of scientists, led by researchers at McMaster and McGill universities, is attacking that belief.
The researchers discovered the gene that is the strongest marker for heart disease can actually be modified by generous amounts of fruit and raw vegetables. The results of their study are published in the current issue of the journal PLoS Medicine.
"We know that 9p21 genetic variants increase the risk of heart disease for those that carry it," said Dr. Jamie Engert, joint principal investigator of the study, who is a researcher in cardiovascular diseases at the Research Institute of the McGill University Health Centre (RI-MUHC) and associate member in the Department of Human Genetics at McGill University. "But it was a surprise to find that a healthy diet could significantly weaken its effect."
The research, which represents one of the largest gene-diet interaction studies ever conducted on cardiovascular disease, involved the analysis of more than 27,000 individuals from five ethnicities -- European, South Asian, Chinese, Latin American and Arab -- and the effect that their diets had on the effect of the 9p21 gene. The results suggest that individuals with the high risk genotype who consumed a prudent diet, composed mainly of raw vegetables, fruits and berries, had a similar risk of heart attack to those with the low risk genotype.
"We observed that the effect of a high-risk genotype can be mitigated by consuming a diet high in fruits and vegetables," said Sonia Anand, joint principal investigator of the study, and a researcher at the Population Health Research Institute and a professor of medicine and epidemiology at the Michael G. DeGroote School of Medicine at McMaster University. "Our results support the public health recommendation to consume more than five servings of fruits or vegetables as a way to promote good health."
"Our research suggests there may be an important interplay between genes and diet in cardiovascular disease," says the study's lead author Dr. Ron Do, who conducted this research as part of his PhD at McGill and is now based at the Center for Human Genetics Research at the Massachusetts General Hospital, Boston, Massachusetts. "Future research is necessary to understand the mechanism of this interaction, which will shed light on the underlying metabolic processes that the 9p21 gene is involved in."
Wednesday, October 12, 2011
Exercise Just as Good as Drugs at Preventing Migraines
Ω
Although exercise is often prescribed as a treatment for migraine, there has not previously been sufficient scientific evidence that it really works. However, research from the Sahlgrenska Academy at the University of Gothenburg, Sweden, has now shown that exercise is just as good as drugs at preventing migraines.
Doctors use a variety of different methods to prevent migraines these days: on the pharmaceutical side a drug based on the substance topiramate has proved effective, while non-medical treatments with well-documented effects include relaxation exercises.
No previous evidence
Exercise is also frequently recommended as a treatment, though there has not been sufficient scientific evidence that it really has any effect on migraine patients.
In a randomized controlled study researchers from the University of Gothenburg's Sahlgrenska Academy have now analysed how well exercise works as a preventative treatment for migraines relative to relaxation exercises and topiramate.
40 minutes of exercise
Published in the journal Cephalalgia, the study involved 91 migraine patients, a third of whom were asked to exercise for 40 minutes three times a week under the supervision of a physiotherapist, with another third doing relaxation exercises, and the final third given topiramate. The study lasted for a total of three months, during which the patients' migraine status, quality of life, aerobic capacity and level of phyical activity were evaluated before, during and after their treatment. Follow-ups were then carried out after three and six months.
Exercise just as effective
The results show that the number of migraines fell in all three groups. Interestingly, there was no difference in the preventative effect between the three treatments.
"Our conclusion is that exercise can act as an alternative to relaxations and topiramate when it comes to preventing migraines, and is particularly appropriate for patients who are unwilling or unable to take preventative medicines," says Emma Varkey, the physiotherapist and doctoral student at the Sahlgrenska Academy who carried out the study.
Ω
Although exercise is often prescribed as a treatment for migraine, there has not previously been sufficient scientific evidence that it really works. However, research from the Sahlgrenska Academy at the University of Gothenburg, Sweden, has now shown that exercise is just as good as drugs at preventing migraines.
Doctors use a variety of different methods to prevent migraines these days: on the pharmaceutical side a drug based on the substance topiramate has proved effective, while non-medical treatments with well-documented effects include relaxation exercises.
No previous evidence
Exercise is also frequently recommended as a treatment, though there has not been sufficient scientific evidence that it really has any effect on migraine patients.
In a randomized controlled study researchers from the University of Gothenburg's Sahlgrenska Academy have now analysed how well exercise works as a preventative treatment for migraines relative to relaxation exercises and topiramate.
40 minutes of exercise
Published in the journal Cephalalgia, the study involved 91 migraine patients, a third of whom were asked to exercise for 40 minutes three times a week under the supervision of a physiotherapist, with another third doing relaxation exercises, and the final third given topiramate. The study lasted for a total of three months, during which the patients' migraine status, quality of life, aerobic capacity and level of phyical activity were evaluated before, during and after their treatment. Follow-ups were then carried out after three and six months.
Exercise just as effective
The results show that the number of migraines fell in all three groups. Interestingly, there was no difference in the preventative effect between the three treatments.
"Our conclusion is that exercise can act as an alternative to relaxations and topiramate when it comes to preventing migraines, and is particularly appropriate for patients who are unwilling or unable to take preventative medicines," says Emma Varkey, the physiotherapist and doctoral student at the Sahlgrenska Academy who carried out the study.
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Tuesday, October 11, 2011
Herbal Supplements May Cause Dangerous Drug Interactions
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Complementary and alternative medical (CAM) treatments such as herbal supplements have become increasingly popular in the United States, especially among older patients and those with chronic pain. However, many of these products can have serious and potentially harmful side effects when combined with medications prescribed during and after surgery, according to a review article in the Journal of the American Academy of Orthopaedic Surgeons (JAAOS).
About 20 percent of prescription users also take an herbal supplement, and those rates are higher — studies suggest between 35 and 70 percent — among orthopaedic patients who are candidates for surgery.
“Herbal remedies are classified as dietary supplements, meaning they are exempt from the safety and efficacy regulations that the U.S. Food and Drug Administration (FDA) requires for prescription and over-the-counter medications,” said David T. Rispler, MD, director of the Grand Rapids/Michigan State University Orthopedic Residency Program. “As a result, individual herbal remedies have not been thoroughly evaluated in large clinical trials, and little information is available on the interactions between drugs and herbs.”
In addition, many herbal products are marketed as “natural” or “homeopathic,” which may lead consumers to assume the products are safe, even when taken with prescription medicines, Dr. Rispler noted. “Herbal supplements can have a negative impact on patients both before and following surgery, and may interact with conventional medicines used to manage chronic conditions.”
“Traditional physician-patient communications, like intake interviews, often do not include the subject of alternative medical products. As a result, patients may fail to report that they are using them and continue to take them along with any prescribed medicines and before surgery, thinking the herbal products pose no risk,” said Dr. Rispler.
Many of the most popular herbal supplements used today can have serious side effects when combined with prescription medicines. For example:
• Feverfew (used for migraine prevention), ginger, cranberry, St. John’s Wort and ginseng can interact with the anti-clotting drug warfarin;
• Feverfew, ginger, and gingko can interact with aspirin;
• Garlic can interfere with anti-clotting medications and the immunosuppressant drug cyclosporine (prevents transplant rejection);
• Valerian (used as a sedative) can intensify anesthetics; and
• St. John’s Wort can interact with immunosuppressive drugs and potentially lead to transplant rejection.
Herbal products marketed for osteoarthritis also can pose serious risks when combined with prescription medications. For example:
• Glucosamine, chondroitin and flavocoxid can affect clotting agents;
• Black cohosh can interact with the cancer drug tamoxifen; and
• Cat’s claw can interact with clotting agents, blood pressure medications and cyclosporine.
Most surgery-related side effects can be avoided by stopping the CAM product at least one to two weeks prior to surgery and during the postoperative period while prescription medications such as blood thinners or antibiotics are being used. The problem arises when physicians do not know that a patient is using a CAM product, Dr. Rispler said.
“One of the main reasons that patients do not disclose the use of a CAM product is that they may not believe it is important information to convey to the physician because they feel they are safe to use and all-natural,” he said. “Patients may also decide not to report CAM product use if they are worried their physician may be prejudiced against the supplement’s use, or believe their physician will not have an understanding of the supplement.”
Although the use of herbal medicines should be monitored by patients’ primary care physicians, Dr. Rispler said orthopaedic surgeons should have an understanding of the potential side effects of some of the most common CAM products used by their patients, and be able to guide them in suspending use prior to surgery.
To help ensure physicians are aware of the products their patients may be using, Dr. Rispler also recommends including CAM product-use questions on health/medical assessment forms to encourage patient disclosure.
“Physician-patient communication often does not include the use of CAM therapies, which results in underreporting of their use,” he said. “To help avoid potential side effects, orthopaedists should develop questionnaires that can be used prior to surgery to help determine if their patients are using CAM products.” Alternatively, patients should also report usage of any herbal products or other supplements they may be taking to all their physicians.
“By opening up a conversation on the use of herbal medications around the time of surgery and compiling a complete list of all prescribed and self-prescribed medications and supplements, patients and physicians may be able to work together to decrease the risk of complications that can occur during and following surgery,” Dr. Rispler said.
Complementary and alternative medical (CAM) treatments such as herbal supplements have become increasingly popular in the United States, especially among older patients and those with chronic pain. However, many of these products can have serious and potentially harmful side effects when combined with medications prescribed during and after surgery, according to a review article in the Journal of the American Academy of Orthopaedic Surgeons (JAAOS).
About 20 percent of prescription users also take an herbal supplement, and those rates are higher — studies suggest between 35 and 70 percent — among orthopaedic patients who are candidates for surgery.
“Herbal remedies are classified as dietary supplements, meaning they are exempt from the safety and efficacy regulations that the U.S. Food and Drug Administration (FDA) requires for prescription and over-the-counter medications,” said David T. Rispler, MD, director of the Grand Rapids/Michigan State University Orthopedic Residency Program. “As a result, individual herbal remedies have not been thoroughly evaluated in large clinical trials, and little information is available on the interactions between drugs and herbs.”
In addition, many herbal products are marketed as “natural” or “homeopathic,” which may lead consumers to assume the products are safe, even when taken with prescription medicines, Dr. Rispler noted. “Herbal supplements can have a negative impact on patients both before and following surgery, and may interact with conventional medicines used to manage chronic conditions.”
“Traditional physician-patient communications, like intake interviews, often do not include the subject of alternative medical products. As a result, patients may fail to report that they are using them and continue to take them along with any prescribed medicines and before surgery, thinking the herbal products pose no risk,” said Dr. Rispler.
Many of the most popular herbal supplements used today can have serious side effects when combined with prescription medicines. For example:
• Feverfew (used for migraine prevention), ginger, cranberry, St. John’s Wort and ginseng can interact with the anti-clotting drug warfarin;
• Feverfew, ginger, and gingko can interact with aspirin;
• Garlic can interfere with anti-clotting medications and the immunosuppressant drug cyclosporine (prevents transplant rejection);
• Valerian (used as a sedative) can intensify anesthetics; and
• St. John’s Wort can interact with immunosuppressive drugs and potentially lead to transplant rejection.
Herbal products marketed for osteoarthritis also can pose serious risks when combined with prescription medications. For example:
• Glucosamine, chondroitin and flavocoxid can affect clotting agents;
• Black cohosh can interact with the cancer drug tamoxifen; and
• Cat’s claw can interact with clotting agents, blood pressure medications and cyclosporine.
Most surgery-related side effects can be avoided by stopping the CAM product at least one to two weeks prior to surgery and during the postoperative period while prescription medications such as blood thinners or antibiotics are being used. The problem arises when physicians do not know that a patient is using a CAM product, Dr. Rispler said.
“One of the main reasons that patients do not disclose the use of a CAM product is that they may not believe it is important information to convey to the physician because they feel they are safe to use and all-natural,” he said. “Patients may also decide not to report CAM product use if they are worried their physician may be prejudiced against the supplement’s use, or believe their physician will not have an understanding of the supplement.”
Although the use of herbal medicines should be monitored by patients’ primary care physicians, Dr. Rispler said orthopaedic surgeons should have an understanding of the potential side effects of some of the most common CAM products used by their patients, and be able to guide them in suspending use prior to surgery.
To help ensure physicians are aware of the products their patients may be using, Dr. Rispler also recommends including CAM product-use questions on health/medical assessment forms to encourage patient disclosure.
“Physician-patient communication often does not include the use of CAM therapies, which results in underreporting of their use,” he said. “To help avoid potential side effects, orthopaedists should develop questionnaires that can be used prior to surgery to help determine if their patients are using CAM products.” Alternatively, patients should also report usage of any herbal products or other supplements they may be taking to all their physicians.
“By opening up a conversation on the use of herbal medications around the time of surgery and compiling a complete list of all prescribed and self-prescribed medications and supplements, patients and physicians may be able to work together to decrease the risk of complications that can occur during and following surgery,” Dr. Rispler said.
Health benefits of broccoli require the whole food, not supplements
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New research has found that if you want some of the many health benefits associated with eating broccoli or other cruciferous vegetables, you need to eat the real thing – a key phytochemical in these vegetables is poorly absorbed and of far less value if taken as a supplement.
The study, published by scientists in the Linus Pauling Institute at Oregon State University, is one of the first of its type to determine whether some of the healthy compounds found in cruciferous vegetables can be just as easily obtained through supplements.
The answer is no.
And not only do you need to eat the whole foods, you have to go easy on cooking them.
"The issue of whether important nutrients can be obtained through whole foods or with supplements is never simple," said Emily Ho, an OSU associate professor in the OSU School of Biological and Population Health Sciences, and principal investigator with the Linus Pauling Institute.
"Some vitamins and nutrients, like the folic acid often recommended for pregnant women, are actually better-absorbed as a supplement than through food," Ho said. "Adequate levels of nutrients like vitamin D are often difficult to obtain in most diets. But the particular compounds that we believe give broccoli and related vegetables their health value need to come from the complete food."
The reason, researchers concluded, is that a necessary enzyme called myrosinase is missing from most of the supplement forms of glucosinolates, a valuable phytochemical in cruciferous vegetables. Without this enzyme found in the whole food, the study found that the body actually absorbs five times less of one important compound and eight times less of another.
Intensive cooking does pretty much the same thing, Ho said. If broccoli is cooked until it's soft and mushy, its health value plummets. However, it can still be lightly cooked for two or three minutes, or steamed until it's still a little crunchy, and retain adequate levels of the necessary enzyme.
The new study was published in the Journal of Agricultural and Food Chemistry. It was supported by the National Institutes of Health.
Broccoli has been of particular interest to scientists because it contains the highest levels of certain glucosinolates, a class of phytochemicals that many believe may reduce the risk of prostate, breast, lung and colorectal cancer. When eaten as a raw or lightly-cooked food, enzymes in the broccoli help to break down the glucosinolates into two valuable compounds of intensive research interest – sulforaphane and erucin.
Studies have indicated that sulforaphane, in particular, may help to detoxify carcinogens, and also activate tumor suppressor genes so they can perform their proper function.
Most supplements designed to provide these glucosinolates have the enzyme inactivated, so the sulforaphane is not released as efficiently. There are a few supplements available with active myrosinase, and whose function more closely resembles that of the whole food, but they are still being tested and not widely available, Ho said.
Small amounts of the myrosinase enzyme needed to break down glucosinolates are found in the human gut, but the new research showed they accomplish that task far less effectively than does whole food consumption.
Although broccoli has the highest levels of glucosinolates, they are also found in cauliflower, cabbage, kale and other cruciferous vegetables. The same cooking recommendations would apply to those foods to best retain their health benefits, Ho said.
Many people take a variety of vitamins, minerals and phytochemicals as supplements, and many of them are efficacious in that form, researchers say. Higher and optimal levels of popular supplements such as vitamins C, E, and fish oil, for instance, can be difficult to obtain through diet alone. Some researchers believe that millions of people around the world have deficient levels of vitamin D, because they don't get enough in their diet or through sun exposure.
But for now, if people want the real health benefits of broccoli, there's a simple guideline.
Eat your vegetables.
New research has found that if you want some of the many health benefits associated with eating broccoli or other cruciferous vegetables, you need to eat the real thing – a key phytochemical in these vegetables is poorly absorbed and of far less value if taken as a supplement.
The study, published by scientists in the Linus Pauling Institute at Oregon State University, is one of the first of its type to determine whether some of the healthy compounds found in cruciferous vegetables can be just as easily obtained through supplements.
The answer is no.
And not only do you need to eat the whole foods, you have to go easy on cooking them.
"The issue of whether important nutrients can be obtained through whole foods or with supplements is never simple," said Emily Ho, an OSU associate professor in the OSU School of Biological and Population Health Sciences, and principal investigator with the Linus Pauling Institute.
"Some vitamins and nutrients, like the folic acid often recommended for pregnant women, are actually better-absorbed as a supplement than through food," Ho said. "Adequate levels of nutrients like vitamin D are often difficult to obtain in most diets. But the particular compounds that we believe give broccoli and related vegetables their health value need to come from the complete food."
The reason, researchers concluded, is that a necessary enzyme called myrosinase is missing from most of the supplement forms of glucosinolates, a valuable phytochemical in cruciferous vegetables. Without this enzyme found in the whole food, the study found that the body actually absorbs five times less of one important compound and eight times less of another.
Intensive cooking does pretty much the same thing, Ho said. If broccoli is cooked until it's soft and mushy, its health value plummets. However, it can still be lightly cooked for two or three minutes, or steamed until it's still a little crunchy, and retain adequate levels of the necessary enzyme.
The new study was published in the Journal of Agricultural and Food Chemistry. It was supported by the National Institutes of Health.
Broccoli has been of particular interest to scientists because it contains the highest levels of certain glucosinolates, a class of phytochemicals that many believe may reduce the risk of prostate, breast, lung and colorectal cancer. When eaten as a raw or lightly-cooked food, enzymes in the broccoli help to break down the glucosinolates into two valuable compounds of intensive research interest – sulforaphane and erucin.
Studies have indicated that sulforaphane, in particular, may help to detoxify carcinogens, and also activate tumor suppressor genes so they can perform their proper function.
Most supplements designed to provide these glucosinolates have the enzyme inactivated, so the sulforaphane is not released as efficiently. There are a few supplements available with active myrosinase, and whose function more closely resembles that of the whole food, but they are still being tested and not widely available, Ho said.
Small amounts of the myrosinase enzyme needed to break down glucosinolates are found in the human gut, but the new research showed they accomplish that task far less effectively than does whole food consumption.
Although broccoli has the highest levels of glucosinolates, they are also found in cauliflower, cabbage, kale and other cruciferous vegetables. The same cooking recommendations would apply to those foods to best retain their health benefits, Ho said.
Many people take a variety of vitamins, minerals and phytochemicals as supplements, and many of them are efficacious in that form, researchers say. Higher and optimal levels of popular supplements such as vitamins C, E, and fish oil, for instance, can be difficult to obtain through diet alone. Some researchers believe that millions of people around the world have deficient levels of vitamin D, because they don't get enough in their diet or through sun exposure.
But for now, if people want the real health benefits of broccoli, there's a simple guideline.
Eat your vegetables.
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