Friday, July 22, 2011



“Bet you can’t eat just one” (as the old potato-chip commercials had it) is, of course, a bet most of us end up losing. But why? Is it simple lack of willpower that makes fatty snacks irresistible, or are deeper biological forces at work?

Some intriguing new research suggests the latter. Scientists in California and Italy reported last week that in rats given fatty foods, the body immediately began to release natural marijuanalike chemicals in the gut that kept them craving more.

The findings are among several recent studies that add new complexity to the obesity debate, suggesting that certain foods set off powerful chemical reactions in the body and the brain. Yes, it’s still true that people gain weight because they eat more calories than they burn. But those compulsions may stem from biological systems over which the individual has no control.

“I do think some people come into the world, and they are more responsive to food,” said Susan Carnell, a research associate at the Columbia University Institute of Human Nutrition. “I think there are many different routes to obesity.”

In the recent rat studies, by a team from the University of California, Irvine, and the Italian Institute of Technology in Genoa, the goal was to measure how taste alone affects the body’s response to food. Among rats given liquid diets high in fat, sugar or protein, the ones who got the fatty liquid had a striking reaction: As soon as it hit their taste buds, their digestive systems began producing endocannabinoids, chemicals similar to those produced by marijuana use.

The compounds serve a variety of functions, including regulation of mood and stress response, appetite, and movement of food through the intestines. Notably, they were released only when the rats tasted fat, not the sugar or protein. The findings were published online last week in The Proceedings of the National Academy of Sciences.

“The most surprising thing to most people, including me,” said an author of the study, Daniele Piomelli, director of drug discovery and development at U.C. Irvine, “is the findings provide a window on how we relate to fatty foods.”

Since fats are essential for cell functioning, Dr. Piomelli continued, “we have this evolutionary drive to recognize fat, and when we have access to it, to consume as much as we possibly can.”

The finding that the signal to eat more fat is released from the gut offers hope for potential new diet drugs. A Food and Drug Administration committee already has rejected one diet drug that blocks endocannabinoids, called Acomplia in Europe, where it was later withdrawn because it had severe psychological side effects, including suicidal thoughts. The new research suggests that the focus might be shifted to endocannabinoids in the gut, which could alleviate side effects in the brain.

In the rat studies, the researchers injected a cannabinoid-blocking drug into the intestines of the rats and found that they lost interest in the fatty food. “The effect is remarkable,” Dr. Piomelli said. “They are no longer interested in feeding. They stop completely. We were amazed.”

A drug based on the research is still years away, but the findings offer practical advice to consumers about the powerful biological forces at play when they snack on fatty junk foods.

“We think we eat it because we like it, but it’s not just because we like, but because we want it,” said Dr. David Kessler, former head of the F.D.A. and author of the book “The End of Overeating” (Rodale, 2009). “It has a lot more to do with our brains and the feedback mechanism to our brains than we realize.”

Other studies have shown that the body’s brain reward centers are strongly affected by the foods we eat.

For example, when obese women were shown pictures of high-calorie foods, their brains showed greater activity in regions associated with anticipating reward than did the brains of normal-weight women. “Reward centers were activated just by saying the words ‘chocolate brownie,’” said Dr. Carnell of Columbia.

The question is whether some people are born more responsive to certain foods, or whether a lifetime of overeating leads to brain and body changes that promote a stronger food response. To shed light on that issue, Dr. Carnell is conducting studies looking at normal-weight teenagers who have obese parents, and as a result are at risk for becoming obese themselves. “I’m interested in whether the brain is responding differently even before they become obese,” she said.

Dr. Kessler notes that consumers need to be aware that the body’s natural signals are often overwhelmed by the abundance of choices and messages about food, so they must be extra vigilant about healthful eating.

“The pull is very strong, and there is a biological reason why food has such power over us,” he said. “It’s a real struggle, and it’s not just a question of being lazy or lack of willpower.

“But just because your brain is being hijacked, that doesn’t mean you don’t have a responsibility to protect yourself.”

Monday, July 18, 2011


You don't usually see it or taste it, but fiber works wonders for your body. Dietary fiber is a known cancer fighter found only in the cell walls of plant foods. For years, studies have pointed to the fact that increased fiber intake decreases the risk of colorectal cancer.
According to a study published in the New England Journal of Medicine (1999) this protective effect may be due to fiber's tendency to add bulk to your digestive system, shortening the amount of time that wastes travel through the colon. As this waste often contains carcinogens, it is best to removed it as quickly as possible.
The Journal of Clinical Nutrition (1999) reported that fiber may also help protect against breast cancer, an effect noted especially with consumption of whole grains and wheat bran. Studies indicate that that high amounts of fiber may also prevent breast cancer by binding to estrogen. When bacteria in the lower intestine break down fiber, a substance called butyrate is produced which may inhibit the growth of tumors of the colon and rectum as reported in the Journal of Oncology Research in 2000. Fiber may also have a protective effect against mouth, throat and esophageal cancers according to a study published in the International Journal of Cancer in 2001.
Most Americans only take in about 10-15 grams of fiber per day. However, studies have shown that to have a cancer preventing effect one needs about 30-35 grams per day. So what should we do? Eat more vegetables!

Monday, July 11, 2011

Best Hospitals are Physician-Run

Top-performing hospitals are typically ones headed by a medical doctor rather than a manager. That is the finding from a new study of what makes a good hospital.

The research, to be published in the elite journal Social Science and Medicine, is the first of its kind. Its conclusions run counter to a modern trend across the western world to put generally trained managers — not those with a medical degree — at the helm of hospitals. This trend has been questioned, particularly by the Darzi Report, which was commissioned by the U.K. National Health Service, but until now there has been no clear evidence.

Amanda Goodall PhD, the author of the study, and a senior researcher at the Institute for the Study of Labor (IZA) in Bonn, Germany, constructed a detailed database on 300 of the most prominent hospitals in the United States. She then traced the professional background and personal history of each leader. The research focused particularly on hospital performance in the fields of cancer, digestive disorders and heart surgery.

The study shows that hospital quality scores are approximately 25% higher in physician-run hospitals than in the average hospital.

Goodall said: “Over the last few decades there has been a growing tendency for hospital boards to appoint managers as CEOs. These findings raise some warning signs over that trend.”

She said: “According to the latest data, outstanding hospitals tend to be those run by somebody with a medical degree. I was surprised by the strength of the pattern. It seems that age-old conventions about having doctors in charge — currently an idea that is out of favor around the world — may turn out to have been right all along.”

Barry Silbaugh M.D., the CEO of American College of Physician Executives, commented: “We are watching Dr Goodall’s research carefully because it seems to finally provide a real evidence-base for physician leadership. This is something we have long supported.”

Goodall stressed that more research would be needed before cause-and-effect could be truly understood. The study, a cross-sectional one, uses data from 2009. “This is an intriguing pattern but these snap-shot results for a single point in time do not prove that doctors make the best heads of hospitals, although they are consistent with that claim. More research following a range of hospitals through time is urgently needed,” she said.

Tuesday, July 5, 2011

To Heal a Heart, Train Harder

Traditionally, heart patients were encouraged to begin slowly and work up to more strenuous activity. New research suggests rigorous workouts benefit heart patients. According to The Wall Street Journal:

Some scientists and clinics are backing the use of high-intensity interval training, which involves short spurts of intense exercise at 85% to 95% of maximum heart rate alternating with periods of moderate exercise. Heart patients have traditionally built up fitness with steady sessions of aerobic exercise aimed at keeping the heart beating at about 70% of its maximum rate. That’s meant to give the heart a workout without risking chest pain or a cardiac event.