Tag: cancer

New scientific evidence that intermittent fasting has health benefits

On By A.P.In fastingLeave a comment

by Charles Q. Choi

Instead of eating three square meals a day, an eating schedule that involves “intermittent fasting” could help fight not just obesity but many related diseases of modern life, such as diabetes, heart disease, cancer and Alzheimer’s, researchers say.

he advice given on fighting obesity usually focuses on consuming fewer calories and exercising more. The benefits of such foods as vegetables, fruits, nuts, fiber and fish, and the value of reducing or eliminating snacks are often also touted.

However, mounting evidence reveals that other key aspects of diet — when and how often people eat — can also play a major role in health. In fact, the most common eating pattern in modern societies of three meals daily, plus snacks, is abnormal from the perspective of human evolution, an international group of researchers wrote in an article published in the journal Proceedings of the National Academy of Sciences.

More and more research shows that intermittent fasting could have benefits, they said.

“Fasting alone is more powerful in preventing and reversing some diseases than drugs,” said Satchidananda Panda, an associate professor of regulatory biology at the Salk Institute for Biological Studies in San Diego, California, and one of the co-authors of the article.

Ancient hunter-gatherers often ate only intermittently, the researchers noted in their article. This suggests that the ability to function at a high level both physically and mentally during extended periods without food may have been crucial in human evolution, and that the human body may have adapted to perform at its best with intermittent fasting.

Such intermittent fasting could consist of eating 500 calories or less either two days each week, or every other day, or not eating breakfast and lunch several days each week, the researchers said.

Prior research suggests that in animals, intermittent fasting can fend off or even reverse such illnesses as cancer, diabetes, heart disease and neurodegenerative disorders. Animal studies suggest that intermittent fasting provides these benefits by allowing the body to respond better to stress that might otherwise damage it. For example, fasting could starve tumors, reduce inflammation, or improve the removal of damaged molecules and other components of cells, the researchers said.

“Intermittent fasting helps the body to rejuvenate and repair, thereby promoting overall health,” Panda told Live Science.

In addition, the body may respond better to meals eaten at some times of the day rather than others because of the body’s circadian rhythms. In the years before artificial light, people depended on natural patterns of day and night, with food primarily eaten during the day and fasting occurring at night. This means that eating at certain times of the day may be healthier for the body’s metabolism — for example, in 2013, two studies in humans suggested that eating meals earlier in the day improved weight loss in overweight and obese people.

Panda said that it may be challenging for people to fast intermittently, instead of eating three meals every day. Eating breakfast is often promoted as a weight-control aid, but recent evidence has suggested it might not be, the researchers said.

Future research needs to further explore the benefits and drawbacks of different types of intermittent fasting in a variety of populations. “Its effectiveness in both preventing and reversing diseases, as well as interaction with standard medications for chronic metabolic diseases, should be tested in appropriate volunteer groups,” Panda said.

http://www.livescience.com/48888-intermittent-fasting-benefits-weight-loss.html

Sitting too much may be twice as dangerous for your health as being obese.

On By A.P.In Health, Obesity1 Comment

There’s been a fast growing body of evidence in the last several years that lack of exercise – or sedentariness – is a major risk factor in health. It’s been linked to heart disease, cancer, and to an early death. And now, a new study finds that lack of exercise may actually be even more of a risk than obesity in early mortality: The researchers calculate that a sedentary lifestyle may actually confer twice the risk of death as being obese. That said, the two are both important and, luckily, closely related: So if you start getting active, you’ll probably lose a little weight along the way, which itself is a very good thing.

The new study looked at data from over 334,000 people who participated in the European Prospective Investigation into Cancer and Nutrition (EPIC) Study. Over a period of 12 years, the participants’ height, weight, and waist circumferences were tracked, along with self-reports of activity levels, both at work and in free time. All-cause mortality (i.e., death from any cause) was the main outcome of interest.

It turned out that lack of physical activity was linked to the greatest risk of death – and the greatest reduction in death risk was in the difference between the lowest two activity groups. In other words, just moving from “inactive” to “moderately inactive” showed the largest reduction in death risk, especially for normal weight people, but true for people of all body weights. And, the authors say, just taking a brisk 20-minute walk per day can move you from one category to the other, and reduce the risk of death anywhere from 16% to 30%.

Using a statistical model, the team also calculated that being sedentary may account for double the death risk of obesity. According to their math, of the 9.2 million deaths in Europe in 2008, about 337,000 were attributable to obesity, whereas 676,000 were attributable to sedentariness.

Another takeaway from the study, however, is that waist circumference is a bigger player in mortality risk than overall body weight, which has certainly been suggested by previous studies. Belly fat seems to be disproportionately linked to chronic health issues like heart disease, stroke, diabetes, cancer, and of course, early mortality. So reducing belly fat is always a significant benefit to one’s health.

“This large study is rather complex in its details, but the take-away messages are actually both clear and simple,” says David L, Katz, Director of the Yale University Prevention Research CenterGriffin Hospital. “At any given body weight, going from inactive to active can reduce the risk of premature mortality substantially. At any given level of activity, going from overweight to a more optimal weight can do the same. We have long known that not all forms of obesity are equally hazardous, and this study reaffirms that. Losing weight if you have an excess around the middle, where it is most dangerous, exerts an influence on mortality comparable to physical activity. Losing excess weight that is not associated with a high waist circumference reduces mortality risk, but less — as we would expect.”

But perhaps the main point in all of this is that being active and being a healthy weight are inextricably linked. Though activity by itself can offer an immediate health benefit if you remain overweight, getting active also leads naturally to loss of body weight. “This study reminds that being both fit and unfat are good for health,” says Katz, “and can add both life to years, and years to life. These are not really disparate challenges, since the physical activity that leads to fitness is on the short list of priorities for avoiding fatness as well. The challenge before us now is for our culture to make it easier to get there from here.”

Earlier this month a study showed that the concept of “healthy obesity” may be very misleading, since health markers in an obese person tend to deteriorate over time. Though the current study suggests that fitness may matter more than fatness, the two are really two sides of a coin: It would be silly to become active and not lose weight — and it would be very hard to do, since the one leads to the other. But perhaps given the great benefits of exercise alone, public health campaigns should focus not just on losing weight, but on encouraging people to add just small amounts physical activity to their lives right off the bat, and to see where it goes from there.

http://www.forbes.com/sites/alicegwalton/2015/01/15/is-lack-of-exercise-worse-for-your-health-than-obesity/

How dark beer can make grilled meat less carcinogenic

On By A.P.In beer, Cancer, carcinogen, dark beer, Food, Guiness, Journal of Agricultural and Food ChemistryJournal of Agricultural and Food Chemistry, Medicine, Memorial Day, polycyclic aromatic hydrocarbons, ScienceLeave a comment

If you’re grilling meat this Memorial Day, you should seriously consider stocking up on Guinness.

Grilling meat is a warm-weather tradition in America, especially on Memorial Day weekend. It’s also an ancient human tradition, uniting friends and family around food and fire as long as our species has existed. Unfortunately, it also unites us around chemicals that can cause cancer.

Warnings like that can make it seem like scientists ruin everything — they already took sitting, late-night snacks and fireworks from us. But science works both ways, and now it has found at least a partial solution for this carnivore’s conundrum. According to a recent study, published in the Journal of Agricultural and Food Chemistry, the secret to safer grilling has been under our noses all along.

Beer is a common ingredient at backyard cookouts, usually as a beverage. But research suggests marinating meat with beer, particularly dark beer, can curb the creation of polycyclic aromatic hydrocarbons (PAHs). These carcinogenic chemicals form as fat and juices drip from meat onto flames or embers, which then send smoky PAHs wafting up to coat the surface of our food.

PAHs can exist in more than 100 different combinations, some of which are found in known toxic cocktails like cigarette smoke and car exhaust. These chemicals have caused tumors, birth defects and reproductive problems in lab animals, according to the U.S. EPA, but the same effects have not been seen in humans. The National Cancer Institute says PAHs “become capable of damaging DNA only after they are metabolized by specific enzymes in the body.” Nonetheless, health concerns raised in a 2002 report have led the European Union to set safety standards for PAHs in food.

Previous studies have shown that beer, wine, tea and rosemary marinades can reduce carcinogens in cooked meat, but until now little was known about how various beer styles affect this phenomenon. And according to the recent study, the kind of beer seems to make a pretty significant difference.

To reach that conclusion, the researchers marinated pork for four hours in one of three beer types: regular pilsner, non-alcoholic pilsner or black beer. They then grilled the pork to well-done on a charcoal grill and tested its PAH levels. Black beer had the most dramatic effect, reducing eight major PAHs to less than half the amount found in unmarinated grilled pork. (The researchers chose eight PAHs that are identified by the EU as “suitable indicators for carcinogenic potency of PAHs in food.”)

The two pilsners also showed an “inhibitory effect” on PAHs, but not as much. The regular pilsner suppressed PAHs by 13 percent, and the non-alcoholic variety went slightly further with 25 percent.

“Thus, the intake of beer-marinated meat can be a suitable mitigation strategy,” the researchers say.

The study’s authors aren’t sure why beer marinade has this effect, or why dark beer fights PAHs better than pilsner does. It isn’t the alcohol, since non-alcoholic pilsner nearly doubled the PAH suppression of its boozier relative. They suspect it might be antioxidant compounds in beer, especially darker beers, since antioxidants could restrict the movement of free radicals that are required for PAH formation. More research will be needed to know for sure, but this theory could help explain why antioxidant-rich red wine, green tea and rosemary extracts also keep carcinogens in check.

Whatever you use, the American Institute for Cancer Research already recommends marinating meat for at least 30 minutes to limit both PAHs and heterocyclic amines (HCAs), another type of chemical compound that can damage DNA. It also suggests grilling fish and poultry more often than red meat or processed meats like hot dogs, which can increase the risk for certain cancers. Reducing temperature, time on the grill and smoke exposure are other options for limiting cancer risk.

And while it can’t take the place of a juicy, beer-marinated pork chop, there’s also another, even more surefire way to cut back your risk: Save some room on the grill for fruits, vegetables and mushrooms.

http://www.mnn.com/food/healthy-eating/blogs/how-dark-beer-can-make-grilled-meat-less-carcinogenic