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18 December 2009

Drinking cups of tea and coffee 'can prevent diabetes'

Tea and coffee drinkers have a lower risk of developing type 2 diabetes, a large body of evidence shows.

And the protection may not be down to caffeine since decaf coffee has the greatest effect, say researchers in Archives of Internal Medicine.

They looked at 18 separate studies involving nearly 500,000 people.

This analysis revealed that people who drink three or four cups of coffee or tea a day cut their risk by a fifth or more, say researchers.

The same amount of decaffeinated coffee had an even bigger effect, lowering risk by a third.

Type 2 diabetes usually starts after the age of 40 and develops when the body can still make some insulin, but not enough, or when the insulin that is produced does not work properly. Type 2 diabetes is treated with a healthy diet and increased physical activity. In addition to this, medication and/or insulin is often required.

If the findings prove true, doctors may well start advising people to put the kettle on as well as take more exercise and watch their weight, say the researchers.

When the authors combined and analysed the data, they found that each additional cup of coffee consumed in a day cut diabetes risk by 7%.

Lead researcher Dr Rachel Huxley, from the University of Sydney in Australia, said because of the finding with decaffeinated coffee, the link is unlikely to be solely related to caffeine.

Instead, other compounds in coffee and tea - including magnesium and antioxidants known as lignans or chlorogenic acids - may be involved.

Special brew

"The identification of the active components of these beverages would open up new therapeutic pathways for the primary prevention of diabetes mellitus.

"If such beneficial effects were observed in interventional trials to be real, the implications for the millions of individuals who have diabetes mellitus, or who are at future risk of developing it, would be substantial."

Dr Victoria King, of Diabetes UK, said: "Without full information about what other factors may be influencing the type 2 diabetes risk of the studies' participants - such as their physical activity levels and diet - as well as what the active ingredient in tea or coffee appears to be, we cannot be sure what, if anything, this observed effect is down to.

"What we can be sure of is that the development of type 2 diabetes is strongly linked to lifestyle, which means that many cases could be prevented by keeping active and eating a healthy balanced diet that is low in fat, salt and sugar with plenty of fruit and vegetables."

Antidepressants linked to increased stroke risk

MIddle-aged women who take antidepressants are at an increased risk of stroke, a major study has found.

A large study of women who have been through the menopause found those taking antidepressants were 45 per cent more likely to suffer a stroke than those of the same age not on the medicines.

The research also found that overall death rates were 32 per cent higher in women on the drugs.

Experts said patients would have to weigh the benefits of the drugs against the increased risk, adding that depression was a serious condition in itself that could prove fatal.

Antidepressants are one of the most commonly prescribed medicines in Britain and in 2008 there were 36 million prescriptions dispensed in England. It means around three million people were taking antidepressants in England last year.

The findings are from an analysis of the wider Women's Health Initiative Study and involved 136,000 women aged between 50 and 79.

Comparisons were made between the 5,500 women were had been prescribed antidepressants since being enrolled in the research and those who had not. There was no difference in the rates of heart attacks but those on antidepressants were 45 per cent more likely to suffer a stroke.

It is not known why there is a link and the researchers said they could not rule out that some of the effect may be due to the depression rather than just the drugs.

The drugs may affect how blood clots, the study said.

The findings were published in the journal Archives of Internal Medicine.

Lead author Dr Jordan Smoller, of the Massachusetts General Hospital, in Boston, America, wrote: "Although these results raise concerns about adverse effects of antidepressants, it is important to note that depression itself has been implicated as a risk factor for coronary heart disease, stroke, early death, and other adverse outcomes. In addition, inadequately treated depression is associated with substantial disability, impairments in quality of life, and health care costs.

"Nevertheless, our results suggest that physicians should be vigilant about controlling other modifiable cardiovascular risk factors in women taking antidepressants. Further research is needed to clarify the risk-benefit ratio of antidepressant use among older women."

The researchers said the risk of an individual woman suffering a stroke is low so even with the increase it remains relatively rare.

They said in the study the chance of an individual woman suffering a stroke in one year was 0.3 per cent for those not taking antidepressants and was 0.43 for those on the medicines.

They added that despite this, because antidepressants are prescribed in such large volumes there are important implications for public health.

Dr Jordan Smoller said: "While this study did find an association between antidepressants and cardiovascular events, additional research needs to be done to determine exactly what it signifies.

"Older women taking antidepressants, like everyone else, should also work on modifying their other risk factors for cardiovascular disease, such as maintaining a healthy weight and controlling cholesterol levels and blood pressure."

Joanne Murphy, Research Liaison Officer for The Stroke Association said: "This study seems to show a link between antidepressants and stroke; however the overall risk for women taking antidepressants is relatively small. More research needs to be done to determine the actual causes.

"We are already aware of links between depression and the risk of stroke and we are currently funding further studies to look into this.

"Everyone can help reduce their risk of stroke by making lifestyle changes, such as reducing their blood pressure, giving up smoking, reducing alcohol intake, improving their diet and getting plenty of exercise. Anyone who is at all concerned should consult their GP."

17 December 2009

Body clock link to heart disease

Scientists have raised the possibility that cardiovascular disease is linked to disturbances in the body's 24-hour clock.

Working on mice, the Japanese team found a genetic risk factor for a form of high blood pressure is influenced by 24-hour or circadian rhythms.

The study appears online in the journal Nature Medicine.

Malfunctions in the body clock - which influences much of the body's chemistry - have been linked to many diseases.

And lead researcher Professor Hitoshi Okamura said the latest study was in line with data which suggested shift workers, long-distance flight crews and people with sleep disorders have a heightened risk of heart problems.

High blood pressure - known as hypertension - can lead to heart attack, stroke, kidney damage, and many other medical problems.

Many genes have been identified as being essential elements making up the circadian clock.

For example, mice lacking a pair of molecules known as cryptochromes have an abnormal circadian rhythm.

The latest study, by Kyoto University, found these mice were vulnerable to high blood pressure because of abnormally high levels of a hormone called aldosterone that prompts water retention in the kidneys.

Strong correlation

The researchers showed that the circadian clock directly controls a gene that plays a key role in production of the hormone.

The researchers say a similar gene is found in humans.

They stress more work is needed to determine whether a misfiring circadian clock can lead to high blood pressure in humans.

But Professor Okamura said the research raised the prospect of new ways to treat hypertension.

Professor Bryan Williams, an expert in hypertension at the University of Leicester, described the study as "fascinating".

He said: "We know that there is a strong correlation between time of day and cardiovascular events, which often coincide with the early morning surge in blood pressure.

"So this does provide some insights into the mechanism that might underpin blood pressure deregulation in some people."

Professor Williams said some people with high blood pressure were known to have high levels of aldosterone.

But he added: "What we don't know is how common this mutation might be in human hypertension."

Professor Jeremy Pearson, associate medical director at the British Heart Foundation, said: "Hypertension is common, but the genes controlling blood pressure are not well understood.

"Their identification will help design better treatments for high blood pressure."

But he also stressed more research was needed before it became clear whether the study had identified a potential target for new treatments.

Fat in diet won't affect weight gain over time

The percentage of calories that a person got from fat, as opposed to protein or carbohydrates, had nothing to do with how much weight they gained in the coming years, the research team found.

The kinds of fat they ate didn't matter either, Dr. Nita Forouhi of the Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK and her colleagues found.

The findings, Forouhi noted in an email to Reuters Health, show that "it is more important to aim for a healthy lifestyle including a balanced healthy diet and regular physical activity, than to focus on fat intake alone as a factor for weight gain."

The role of dietary fat content in obesity and weight gain is still controversial, Forouhi and her team note. To investigate, they looked at data on nearly 90,000 men and women from six different countries participating in the European Prospective Investigation into Cancer and Nutrition Study. Participants were followed for up to 10 years.

Average fat intake ranged from 31.5 percent to 36.5 percent of total calories. On average, people gained about a quarter of a pound every year. But analyses that accounted for several factors found no relationship between how much weight people gained and how much fat they ate, or their intake of polyunsaturated fats versus saturated fats.

The findings shouldn't be seen as showing that people can eat as much fat as they want, Forouhi said. "That would be absurd, given so much evidence that already exists on the potential harms of diets high in saturated or trans-fats for heart health for instance," the researcher said.

In the US, she added, dietary recommendations state that people should maintain a fat intake that is 20 percent to 35 percent of total calories, and eat "healthy" fats from fish, nuts, and vegetable oils instead of "unhealthy" saturated and trans fats.

She added: "The healthiest way to avoid weight gain is to make sure that, when appropriate, total calorie intake is limited by reducing one's intake of added sugars, fats, and alcohol, which all provide calories but few or no essential nutrients, to watch portion sizes of food (so food portions consumed do not increase in size over time), and at the same time take regular physical activity."

SOURCE: American Journal of Clinical Nutrition, December 200

Antioxidants may boost colon health: Study

Selenium-based antioxidant supplements may prevent the development of new colon polyps in people with a history of polyp formation, says a new study.

Over 400 people participated in the study, which saw them receive either placebo or a antioxidant-rich supplement containing selenomethionnine, zinc, and vitamins A, C, and E. At the end of the study people in the antioxidant group experienced a 40 per cent reduction in the incidence of new polyps of the large bowel.

“Our study is the first intervention trial specifically designed to evaluate the efficacy of the selenium-based antioxidant compound on the risk of developing metachronous adenomas,” said lead researcher Luigina Bonelli, MD, from Italy’s National Institute for Cancer Research in Genoa.

The study represents another step on the ladder of supporting the potential anti-cancer effects of the mineral. Earlier this year, the US Food and Drug Administration said there is “no credible evidence” to support qualified health claims for selenium dietary supplements and a reduced risk of urinary tract cancers other than bladder cancer, lung and other respiratory tract cancers, colon and other digestive tract cancers, brain cancer, liver cancer, or breast cancer.

The research findings are being presented at the American Association for Cancer Research Frontiers in Cancer Prevention Research Conference, held in Houston. NutraIngredients has not seen the full data.

Adenomatous polyps (or adenoma) are benign lesions of the large bowel that, in time, could progress to cancer, explain the researchers. Even though only a small proportion of adenomas will develop into cancer, it is said that almost 70 to 80 per cent of colorectal cancer stems from an adenoma.

Study details

Bonelli and her co-workers randomly assigned the 411 participants aged between 25 and 75 to receive either placebo or the antioxidant supplement. The supplement provided daily doses of 200 micrograms of selenomethionnine, 30 milligrams of zinc, 6,000 IU of vitamin A, 180 milligrams of vitamin C, and 30 milligrams of vitamin E. All the participants had already undergone surgery to remove one or more colorectal adenomas.

“Our results indicated that individuals who consumed antioxidants had a 40 per cent reduction in the incidence of metachronous adenomas of the large bowel,” said Bonelli. “It is noteworthy that the benefit observed after the conclusion of the trial persisted through 13 years of follow up.”

Selenium and prostate health – controversial or convincing?

While the science may be lacking for selenium and colon health, a greater body of science exists for the mineral and prostate health. However, this subject is controversial. A number of studies, most notably the Nutritional Prevention of Cancer study and the Alpha-tocopherol, Beta-carotene Cancer Prevention study, have reported that the nutrients, alone or in combination, may reduce the risk of prostate cancer.

With over half a million new cases of prostate cancer are diagnosed every year world wide, and the cancer directly causing over 200,000 deaths, potential preventive measures are highly desirable. Despite great promise over vitamin E and selenium, recent results from the Selenium and Vitamin E Cancer Prevention Trial (SELECT) reported no significant differences between any of the groups in relation to prostate cancer risk.

The results were greeted with disappointment, while many in both academia and industry indicating that, given positive results from previous clinical trials and epidemiological studies, the design of SELECT, including the supplements used, may have undermined the results.

Oxygen Therapy Can Help Cluster Headaches

"It feels like a burning hot poker being shoved through your eye while an elephant stands on your temple, while someone is punching you in the back of the head and pulling on your hair," said Justin Ott, 31, when describing the pain of a cluster headache.

Ott has suffered from cluster headaches for 10 years, and was motivated to chronicle the debilitating pain -- sometimes called a "suicide headache" -- in a documentary film.

Doctors estimate only 0.3 percent of the population suffers from cluster headaches, and that men are much more likely to be affected.

"From when you first feel it start, and when it comes to full strength, it's five minutes, maybe," said Ott, a writer, producer, director and cinematographer from Weehawken, N.J. "Everybody's different, but if left untreated it can go on for 30 minutes to 60 minutes."

Now, new research suggests that sufferers like Ott can take advantage of a relatively simple treatment to help control the excruciating pain of cluster headaches -- a treatment called oxygen therapy.

Once a person feels a cluster headache coming on, he or she can often stop the headache in its tracks by breathing with a high-flow oxygen face mask.

Oxygen therapy has been used by some headache specialists for 30 years, but has, until now, been considered experimental because there have been no clinical trials proving its effectiveness. Researchers in the United Kingdom treated 76 adults with either high-flow oxygen or a placebo of high-flow normal air for 15 minutes.
Their study, published Tuesday in the Journal of the American Medical Association, found that 78 percent of those on oxygen reported immediate relief compared to only 20 percent receiving the placebo.

Dr. Allan Purdy of the Queen Elizabeth II Health Sciences Center in Canada said that he thought the research was an "excellent study… an evidence-based trial to confirm what we have known and used in practice for years."

Although the study was one of the first to investigate using oxygen to treat cluster headaches, Ott and other cluster headache survivors have taught each other to use the treatment for years.

"Oxygen really, is the best thing. If I'm at home and I get an attack, that's my first thing, is the oxygen," said Ott. "I have tanks all around my house."

14 December 2009

Adequate sleep tied to healthier diets in truckers

NEW YORK (Reuters Health) - Getting plenty of sleep not only helps keep truck drivers safe and alert on the road, it also seems to fuel healthy eating habits, new research hints.

In surveys of truckers working at U.S. trucking terminals, those who felt they regularly got adequate sleep tended to consume more fruits and vegetables and fewer sugary drinks and snacks, Dr. Orfeu M. Buxton, at Harvard Medical School in Boston, Massachusetts, and colleagues found.

These real-world findings are consistent with laboratory studies showing that insufficient sleep increases hunger and "induces greater eating, especially unnecessary snacking," Buxton noted in an email to Reuters Health.

Buxton and associates assessed self-reported diet, sleep, and job-related factors of 542 male Teamster union members who were 49 years old on average.

Sixty-six percent worked as pick-up and delivery truck drivers, 20 percent as over-the-road truckers, and 15 percent served dual roles as dockworkers and truck drivers, they note in the American Journal of Public Health.

Most of the workers (87 percent) were satisfied with their job and a little more than half (52 percent) said they got enough nightly shuteye "to feel rested upon waking up."

These well-rested truckers also said they ate an average of about 3 servings of fruits and vegetables (not including French fries), less than one serving of a sugar-added drink, and less than half a serving of a sugary snack daily.

By contrast, truckers reporting insufficient sleep reported eating about two fruit and vegetable servings, and slightly more than one sugary drink and nearly one sugary snack each day.

The investigators conclude that workplace programs to encourage adequate worker sleep may have positive benefits on employee health

The 7 foods experts won't eat

How healthy (or not) certain foods are—for us, for the environment—is a hotly debated topic among experts and consumers alike, and there are no easy answers. But when Prevention talked to the people at the forefront of food safety and asked them one simple question—“What foods do you avoid?”—we got some pretty interesting answers. Although these foods don’t necessarily make up a "banned” list, as you head into the holidays—and all the grocery shopping that comes with it—their answers are, well, food for thought:

1. Canned Tomatoes

The expert: Fredrick vom Saal, PhD, an endocrinologist at the University of Missouri who studies bisphenol-A

The problem: The resin linings of tin cans contain bisphenol-A, a synthetic estrogen that has been linked to ailments ranging from reproductive problems to heart disease, diabetes, and obesity. Unfortunately, acidity (a prominent characteristic of tomatoes) causes BPA to leach into your food. Studies show that the BPA in most people's body exceeds the amount that suppresses sperm production or causes chromosomal damage to the eggs of animals. "You can get 50 mcg of BPA per liter out of a tomato can, and that's a level that is going to impact people, particularly the young," says vom Saal. "I won't go near canned tomatoes."

The solution: Choose tomatoes in glass bottles (which do not need resin linings), such as the brands Bionaturae and Coluccio. You can also get several types in Tetra Pak boxes, like Trader Joe's and Pomi.

14 worst health mistakes even smart women make.

2. Corn-Fed Beef

The expert: Joel Salatin, co-owner of Polyface Farms and author of half a dozen books on sustainable farming

The problem: Cattle evolved to eat grass, not grains. But farmers today feed their animals corn and soybeans, which fatten up the animals faster for slaughter. More money for cattle farmers (and lower prices at the grocery store) means a lot less nutrition for us. A recent comprehensive study conducted by the USDA and researchers from Clemson University found that compared with corn-fed beef, grass-fed beef is higher in beta-carotene, vitamin E, omega-3s, conjugated linoleic acid (CLA), calcium, magnesium, and potassium; lower in inflammatory omega-6s; and lower in saturated fats that have been linked to heart disease. "We need to respect the fact that cows are herbivores, and that does not mean feeding them corn and chicken manure," says Salatin.

The solution: Buy grass-fed beef, which can be found at specialty grocers, farmers' markets, and nationally at Whole Foods. It's usually labeled because it demands a premium, but if you don't see it, ask your butcher.

25 ridiculously healthy foods you should be eating now.

3. Microwave Popcorn

The expert: Olga Naidenko, PhD, a senior scientist for the Environmental Working Group,

The problem: Chemicals, including perfluorooctanoic acid (PFOA), in the lining of the bag, are part of a class of compounds that may be linked to infertility in humans, according to a recent study from UCLA. In animal testing, the chemicals cause liver, testicular, and pancreatic cancer. Studies show that microwaving causes the chemicals to vaporize—and migrate into your popcorn. "They stay in your body for years and accumulate there," says Naidenko, which is why researchers worry that levels in humans could approach the amounts causing cancers in laboratory animals. DuPont and other manufacturers have promised to phase out PFOA by 2015 under a voluntary EPA plan, but millions of bags of popcorn will be sold between now and then.

The solution: Pop natural kernels the old-fashioned way: in a skillet. For flavorings, you can add real butter or dried seasonings, such as dillweed, vegetable flakes, or soup mix.

Your nutritional guide to grocery shopping.

4. Nonorganic Potatoes

The expert: Jeffrey Moyer, chair of the National Organic Standards Board

The problem: Root vegetables absorb herbicides, pesticides, and fungicides that wind up in soil. In the case of potatoes—the nation's most popular vegetable—they're treated with fungicides during the growing season, then sprayed with herbicides to kill off the fibrous vines before harvesting. After they're dug up, the potatoes are treated yet again to prevent them from sprouting. "Try this experiment: Buy a conventional potato in a store, and try to get it to sprout. It won't," says Moyer, who is also farm director of the Rodale Institute (also owned by Rodale Inc., the publisher of Prevention). "I've talked with potato growers who say point-blank they would never eat the potatoes they sell. They have separate plots where they grow potatoes for themselves without all the chemicals."

The solution: Buy organic potatoes. Washing isn't good enough if you're trying to remove chemicals that have been absorbed into the flesh.

14 ways to make veggies less boring.

5. Farmed Salmon

The expert: David Carpenter, MD, director of the Institute for Health and the Environment at the University at Albany and publisher of a major study in the journal Science on contamination in fish.

The problem: Nature didn't intend for salmon to be crammed into pens and fed soy, poultry litter, and hydrolyzed chicken feathers. As a result, farmed salmon is lower in vitamin D and higher in contaminants, including carcinogens, PCBs, brominated flame retardants, and pesticides such as dioxin and DDT. According to Carpenter, the most contaminated fish come from Northern Europe, which can be found on American menus. "You can only safely eat one of these salmon dinners every 5 months without increasing your risk of cancer," says Carpenter, whose 2004 fish contamination study got broad media attention. "It's that bad." Preliminary science has also linked DDT to diabetes and obesity, but some nutritionists believe the benefits of omega-3s outweigh the risks. There is also concern about the high level of antibiotics and pesticides used to treat these fish. When you eat farmed salmon, you get dosed with the same drugs and chemicals.

The solution: Switch to wild-caught Alaska salmon. If the package says fresh Atlantic, it's farmed. There are no commercial fisheries left for wild Atlantic salmon.

Delicious and easy fish recipes

6. Milk Produced with Artificial Hormones

The expert: Rick North, project director of the Campaign for Safe Food at the Oregon Physicians for Social Responsibility and former CEO of the Oregon division of the American Cancer Society

The problem: Milk producers treat their dairy cattle with recombinant bovine growth hormone (rBGH or rBST, as it is also known) to boost milk production. But rBGH also increases udder infections and even pus in the milk. It also leads to higher levels of a hormone called insulin-like growth factor in milk. In people, high levels of IGF-1 may contribute to breast, prostate, and colon cancers. "When the government approved rBGH, it was thought that IGF-1 from milk would be broken down in the human digestive tract," says North. As it turns out, the casein in milk protects most of it, according to several independent studies. "There's not 100% proof that this is increasing cancer in humans," admits North. "However, it's banned in most industrialized countries."

The solution: Check labels for rBGH-free, rBST-free, produced without artificial hormones, or organic milk. These phrases indicate rBGH-free products.

Don’t be fooled by these 11 health food imposters.

7. Conventional Apples

The expert: Mark Kastel, former executive for agribusiness and codirector of the Cornucopia Institute, a farm-policy research group that supports organic foods

The problem: If fall fruits held a "most doused in pesticides contest," apples would win. Why? They are individually grafted (descended from a single tree) so that each variety maintains its distinctive flavor. As such, apples don't develop resistance to pests and are sprayed frequently. The industry maintains that these residues are not harmful. But Kastel counters that it's just common sense to minimize exposure by avoiding the most doused produce, like apples. "Farm workers have higher rates of many cancers," he says. And increasing numbers of studies are starting to link a higher body burden of pesticides (from all sources) with Parkinson's disease.

The solution: Buy organic apples. If you can't afford organic, be sure to wash and peel them first.