By now, we are all (painfully) aware of the associations between some cancers and excess pounds. We are equally aware of the difficulty of maintaining, let alone losing, weight after cancer treatment. Some people are successful with one kind of diet and some with another, and some people can't shed pounds no matter what they do.
This article from The New York Times is somewhat reassuring--or at least is confirming what we know. Everyone is different, and there is no one diet that works for us all, and for some of us, it is really, really tough.
One Weight-Loss Approach Fits All? No, Not Even Close
Dr. Frank Sacks, a professor of nutrition at Harvard, likes to challenge his audience when he gives lectures on obesity. “If you want to make a great discovery,” he tells them, figure out this: Why do some people lose 50 pounds on a diet while others on the same diet gain a few pounds?
Then he shows them data from a study he did that found exactly that effect.
Dr. Sacks’s challenge is a question at the center of obesity research today. Two people can have the same amount of excess weight, they can be the same age, the same socioeconomic class, the same race, the same gender. And yet a treatment that works for one will do nothing for the other.
The problem, researchers say, is that obesity and its precursor — being overweight — are not one disease but instead, like cancer, they are many. “You can look at two people with the same amount of excess body weight and they put on the weight for very different reasons,” said Dr. Arya Sharma, medical director of the obesity program at the University of Alberta.
Not only can that explain why treatment is so difficult and results so wildly variable, but it can explain why prevention efforts often fail. If obesity is many diseases, said Dr. Lee Kaplan, director of the obesity, metabolism and nutrition institute at Massachusetts General Hospital, there can be many paths to the same outcome. It makes as much sense to insist there is one way to prevent all types of obesity — get rid of sugary sodas, clear the stores of junk foods, shun carbohydrates, eat breakfast, get more sleep — as it does to say
you can avoid lung cancer by staying out of the sun, a strategy specific to skin cancer.
One focus of research is to figure out how many types of obesity there are — Dr. Kaplan counts 59 so far — and how many genes can contribute.
Read more: http://www.nytimes.com/2016/12/12/health/weight-loss-obesity.html