Chlorophyll in green vegetables can prevent cancer

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A recent study at Oregon State University found that the chlorophyll in green vegetables offers protection against cancer when tested against the modest carcinogen exposure levels most likely to be found in the environment.

The findings, published in the journal Food and Chemical Toxicology, were done using 12,360 rainbow trout as laboratory models, instead of more common laboratory mice. Rodent studies are much more expensive, forcing the use of fewer specimens and higher carcinogen exposures.

“There’s considerable evidence in epidemiologic and other clinical studies with humans that chlorophyll and its derivative, chlorophyllin, can protect against cancer,” said Tammie McQuistan, a research assistant working with George Bailey, a professor emeritus in the Linus Pauling Institute at OSU.

The trout were exposed to fairly moderate levels of a known carcinogen, but also given chlorophyll. This reduced their number of liver tumors by 29-64 percent, and stomach tumors by 24-45 percent.

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Dispelling the low-fat-is-healthy myth

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Dozens of studies, many from Harvard School of Public Health (HSPH) researchers, have shown that low-fat diets are no better for health than moderate- or high-fat diets—and for many people, may be worse.

To combat this "low fat is best" myth, nutrition experts at HSPH and chefs and registered dietitians at The Culinary Institute of America (CIA) have developed five new muffin recipes that incorporate healthy fats and whole grains, and use a lighter hand on the salt and sugar. Their goal? To "make over" the ubiquitous low-fat muffin, touted as a "better-for-you" choice when in fact low-fat muffins often have reduced amounts of heart-healthy fats, such as liquid plant oils, but boast plenty of harmful carbohydrates in the form of white flour and sugar.

Other low-fat processed foods are not much better, and are often higher in sugar, carbohydrates, or salt than their full-fat counterparts. For good health, type of fat matters more than amount. Diets high in heavily processed carbohydrates can lead to weight gain and an increased risk of type 2 diabetes and heart disease.

"It's time to end the low-fat myth," said Walter Willett, professor of epidemiology and nutrition and chair of the Department of Nutrition at HSPH. "Unfortunately, many well-motivated people have been led to believe that all fats are bad and that foods loaded with white flour and sugar are healthy choices. This has clearly contributed to the epidemic of diabetes we are experiencing and premature death for many. The lesson contained in these healthy muffins—that foods can be both tasty and good for you—can literally be life-saving."

A regular blueberry muffin from a national coffee shop chain has 450 calories on average and most of those calories come from carbohydrates, primarily white flour and sugar. However, now that national chains have eliminated trans fats, a regular muffin does have heart-healthy fat, usually from soybean or canola oil. A low-fat muffin has about the same amount of calories, but contains more carbohydrates and sugar—and about 60% more sodium (700 milligrams)—than a regular muffin.

The new Blueberry Muffin recipe offered by HSPH and the CIA is less than half the size of a coffee shop muffin and contains just 130 calories. It is made with a mixture of whole wheat, white, and almond flour and uses canola oil, a healthy fat. (See "Blueberry Muffin Battle" for a nutritional comparison of the three types of blueberry muffins: www.hsph.harvard.edu/nutritionsource/what-should-you-eat/blueberry-muffin-battle/index.html)

"There are so many ingredients available to home bakers who want to offer their families healthful, flavorful baked goods," says Richard Coppedge, Jr., chef-instructor at the CIA and a Certified Master Baker. "These five recipes not only include a wide variety of whole grain and nut flours; they also demonstrate how more unusual ingredients like canned chickpeas and extra virgin olive oil can be used in baking."

The CIA and HSPH offer a dozen healthy baking tips that professional chefs and home cooks can use to build a healthier muffin. Here are a few of their tips:

- Downsize the portions. The mega-muffins popular in bake shops are two to three times the size of the muffins your grandmother might have baked.

- Go whole on the grains. It's easy to substitute whole wheat flour for 50% of the white flour in recipes without harming taste or texture. And with a few recipe alterations, delicious muffins can be made with 100% whole grains. See the Lemon Chickpea Breakfast Muffin and the Whole Wheat Banana Nut Muffin recipes as examples.

- Slash the sugar. You can cut 25% of the sugar from most standard muffin recipes without any negative impact on flavor or texture, and in some recipes, cut back even more.

- Pour on the oil. Liquid plant oils—canola, extra virgin olive oil, corn, sunflower, and others—help keep whole-grain muffins moist and are a healthier choice than melted butter or shortening.

- Bring out the nuts. For extra protein and an additional source of healthy fats, add chopped nuts.

- Scale back the salt. The best way to reduce salt is to make a smaller muffin and to pair muffins with foods, such as vegetables and fruits, that are sodium-free.
Pump up the produce—and flavor! Fresh whole fruit and unsweetened dried fruit naturally contain sugar, but unlike other sweeteners, they also contain fiber and important nutrients. Using fruit in your muffins means you can have a lighter hand on the added sugar. Cooked or raw vegetables, such as caramelized onions, sliced jalapeños, and chives and other fresh herbs—together with a whole range of spices—can add interesting textures and savory flavors to muffins.

The muffin recipes and photos, baking tips, a Q & A on why it's time to end the low-fat myth, and a handy chart showing how to find foods with healthy fats are all available on The Nutrition Source, a nutrition website from the Harvard School of Public Health: www.hsph.harvard.edu/nutritionsource/what-should-you-eat/muffin-makeover/index.html

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Increase dietary fiber, decrease disease

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Review confirms benefits of more roughage in the diet

We should all be eating more dietary fiber to improve our health - that's the message from a health review by scientists in India. The team has looked at research conducted into dietary fiber during the last few decades across the globe and now suggests that to avoid initial problems, such as intestinal gas and loose stool, it is best to increase intake gradually and to spread high-fiber foods out throughout the day, at meals and snacks. Writing in the International Journal of Food Safety, Nutrition and Public Health, the team offers fruit, vegetables, whole-grain foods, such as muesli and porridge, beans and pulses, as readily available foods rich in dietary fiber.

Dietary fiber, also known as roughage, is the general term of the non-digestible parts of the fruit and vegetable products we eat. There are two forms soluble and insoluble. Soluble (prebiotic, viscous) fiber that is readily broken down or fermented in the colon into physiologically active byproducts and gases. The second form is insoluble fiber, which is metabolically inert, but absorbs water as it passes through the digestive system, providing bulk for the intestinal muscles to work against and easing defecation.

Vikas Rana of the Rain Forest Research Institute, in Assam, India, and colleagues point out that research has shown that modern food habits have, it seems, led to an increase in the incidence of obesity, cardiovascular diseases, and type 2 diabetes. These are growing more common even in developing nations where a "western" diet of highly processed foods, high in sugars and saturated fats, beef and dairy products and low in dietary fiber is displacing more traditional options. The team suggests that evidence points to a loss of dietary fiber in the diet as being a major risk factor for health problems but one of the simplest to remedy without recourse to major changes in diet or the addition of supplements or so-called functional foods and nutraceuticals to the diet.

Given that dietary fiber has physiological actions such as reducing cholesterol and attenuating blood glucose, maintaining gastrointestinal health, and positively affecting calcium bioavailability and immune function, it is important for the current generation and future generations that this component of our diets be reasserted through education and information.

"Consuming adequate quantities of DF can lead to improvements in gastrointestinal health, and reduction in susceptibility to diseases such as diverticular disease, heart disease, colon cancer, and diabetes. Increased consumption has also been associated with increased satiety and weight loss," the team concludes. Given the ready availability particularly in the West and in the relatively richer parts of the developing world of vegetables, fruit and other foods high in dietary fiber it is a matter of recommending that people eat more dietary fiber rather than consistently taking the unhealthy low-fiber option throughout their lives.

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Omega-3 fatty acids could prevent and treat nerve damage

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Research from Queen Mary, University of London suggests that omega-3 fatty acids, which are found in fish oil, have the potential to protect nerves from injury and help them to regenerate.

When nerves are damaged because of an accident or injury, patients experience pain, weakness and muscle paralysis which can leave them disabled, and recovery rates are poor.

The new study, published this week in the Journal of Neuroscience*, suggests that omega-3 fatty acids could play a significant role in speeding recovery from nerve injury.

The study focused on peripheral nerve cells. Peripheral nerves are the nerves which transmit signals between the brain and spinal cord, and the rest of the body.

These nerves have the ability to regenerate but, despite advances in surgical techniques, patients usually only have good recovery when their injury is minor.

Omega-3 fatty acids are vital for the body's normal growth and development and have been widely researched for their health benefits. Because the body cannot manufacture omega-3 fatty acids, they have to be consumed in foods such as oily fish.

In the new study, researchers first looked at isolated mouse nerve cells. They simulated the type of damage caused by accident or injury, by either stretching the cells or starving them of oxygen. Both types of damage killed a significant number of nerve cells but enrichment with omega-3 fatty acids in cells gave them significant protection and decreased cell death.

Next the researchers studied the sciatic nerves of mice. They found that a high level of omega-3 fatty acids helped mice to recover from sciatic nerve injury more quickly and more fully, and that their muscles were less likely to waste following nerve damage.

The research was carried out by a group led by Adina Michael-Titus, Professor of Neuroscience at Barts and The London Medical School and lead of the Neurotrauma and Neurodegeneration group in the Centre for Neuroscience and Trauma, Queen Mary, University of London.

She explained: "Our previous research has shown that these fatty acids could have beneficial effects in a number of neurological conditions. This new study suggests that they could also have a role in treating peripheral nerve injuries.

"More work is needed but our research indicates that omega-3 fatty acids can protect damaged nerve cells, which is a critical first step in a successful neurological recovery."

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Why coffee drinking reduces the risk of Type 2 diabetes

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Why do heavy coffee drinkers have a lower risk of developing Type 2 diabetes, a disease on the increase around the world that can lead to serious health problems? Scientists are offering a new solution to that long-standing mystery in a report in ACS' Journal of Agricultural & Food Chemistry.

Ling Zheng, Kun Huang and colleagues explain that previous studies show that coffee drinkers are at a lower risk for developing Type 2 diabetes, which accounts for 90-95 percent of diabetes cases in the world. Those studies show that people who drink four or more cups of coffee daily have a 50 percent lower risk of Type 2 diabetes. And every additional cup of coffee brings another decrease in risk of almost 7 percent. Scientists have implicated the misfolding of a substance called human islet amyloid polypeptide (hIAPP) in causing Type 2 diabetes, and some are seeking ways to block that process. Zheng and Huang decided to see if coffee's beneficial effects might be due to substances that block hIAPP.

Indeed, they identified two categories of compounds in coffee that significantly inhibited hIAPP. They suggest that this effect explains why coffee drinkers show a lower risk for developing diabetes. "A beneficial effect may thus be expected for a regular coffee drinker," the researchers conclude.

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Moderate red wine drinking may help cut women's breast cancer risk

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Drinking red wine in moderation may reduce one of the risk factors for breast cancer, providing a natural weapon to combat a major cause of death among U.S. women, new research from Cedars-Sinai Medical Center shows.

The study, published online in the Journal of Women's Health, challenges the widely-held belief that all types of alcohol consumption heighten the risk of developing breast cancer. Doctors long have determined that alcohol increases the body's estrogen levels, fostering the growth of cancer cells.

But the Cedars-Sinai study found that chemicals in the skins and seeds of red grapes slightly lowered estrogen levels while elevating testosterone among premenopausal women who drank eight ounces of red wine nightly for about a month.

White wine lacked the same effect.

Researchers called their findings encouraging, saying women who occasionally drink alcohol might want to reassess their choices.

"If you were to have a glass of wine with dinner, you may want to consider a glass of red," said Chrisandra Shufelt, MD, assistant director of the Women's Heart Center at the Cedars-Sinai Heart Institute and one of the study's co-authors. "Switching may shift your risk."

Shufelt noted that breast cancer is the leading type of women's cancer in the U.S., accounting for more than 230,000 new cases last year, or 30 percent of all female cancer diagnoses. An estimated 39,000 women died from the disease in 2011, according to the American Cancer Society.

In the Cedars-Sinai study, 36 women were randomized to drink either Cabernet Sauvignon or Chardonnay daily for almost a month, then switched to the other type of wine. Blood was collected twice each month to measure hormone levels.

Researchers sought to determine whether red wine mimics the effects of aromatase inhibitors, which play a key role in managing estrogen levels. Aromatase inhibitors are currently used to treat breast cancer.

Investigators said the change in hormone patterns suggested that red wine may stem the growth of cancer cells, as has been shown in test tube studies.

Co-author Glenn D. Braunstein, MD, said the results do not mean that white wine increases the risk of breast cancer but that grapes used in those varieties may lack the same protective elements found in reds.

"There are chemicals in red grape skin and red grape seeds that are not found in white grapes that may decrease breast cancer risk," said Braunstein, vice president for Clinical Innovation and the James R. Klinenberg, MD, Chair in Medicine.

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COUCH POTATO OR ATHLETE? A HAPPY MEDIUM KEEPS COLDS AT BAY!

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Battling colds and doing (or pledging to do) more exercise are familiar activities for most of us in January. But different levels of exercise can actually significantly increase or decrease your chances of catching a respiratory infection, says Professor Mike Gleeson from Loughborough University.

While regular moderate exercise can reduce the risk of catching cold-like infections, prolonged strenuous exercise, such as marathons, can make an individual more susceptible. This is a topical area of research in the year of the Olympics, says Professor Gleeson talking at the Association for Science Education (ASE) Conference on Friday, on behalf of the Society for General Microbiology and the British Society for Immunology.

Upper- respiratory tract infections (URTIs) are acute infections that affect the nose, throat and sinuses, and include the common cold, tonsillitis, sinusitis and flu. Viruses that circulate in the environment usually cause URTIs. While we are constantly exposed to these viruses, it is the status of our immune system that determines whether we succumb to infection or not. Exercise can have both a positive and negative effect on immune function, combined with genetics and other external factors like stress, poor nutrition and lack of sleep. Collectively these factors determine an individual’s susceptibility to infection.

Professor Gleeson explains why the exercise factor is an interesting one. “If you have a tendency to be a couch potato then you probably have an average risk of catching an infection – typically 2-3 URTIs per year. Research shows that those undertaking regular moderate exercise (e.g. a daily brisk walk), can reduce their chance of catching a respiratory infection, such as a cold, by up to almost a third.” This effect has been shown to be the result of the cumulative effect of exercise leading to long-term improvement in immunity. “Conversely, in periods following prolonged strenuous exercise, the likelihood of an individual becoming ill actually increases. In the weeks following a marathon, studies have reported a 2-6 fold increase in the risk of developing an upper respiratory infection,” said Professor Gleeson. “The heavy training loads of endurance athletes make them more susceptible to URTIs and this is an issue for them as infections can mean missing training sessions or underperforming in competitions.”

The major players in this immune regulation are immune cells called Natural Killer (NK) cells which are important weapons in the fight against viral infections. NK cells recognise viral-infected cells as foreign invaders and force them to commit suicide.” During moderate exercise the activity of NK cells is enhanced, whereas stressful endurance activities such as marathons can turn down NK cell activity. These changes are tightly regulated by stress hormones and other immune cells,” explained Professor Gleeson.

There is a clear take-home message from our current understanding of the link between exercise and immune function. “Moderate exercise has a positive effect on the immune system. So to keep colds at bay, a brisk daily walk should help - it’s all about finding a happy medium,” said Professor Gleeson.

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