JAMA Network | JAMA | Lifespan Weighed Down by Diet
▻http://jama.jamanetwork.com/article.aspx?articleID=2512347
Notamment la restriction calorique au long cours,
Although many factors influence body weight, the obesity epidemic is, at least in part, related to the confluence of uncertain science and special interests. For years, the public health approach to obesity has been based on the notion that “all calories are alike” and weight loss will result from simply eating less and being more active. This way of thinking implicitly places primary responsibility on individuals to control their calorie balance, while exonerating the food industry from aggressively marketing low-quality products. If all calories are alike, then a person could consume sugary beverages and other unhealthful foods as long as that person consumes less of other foods or gets more exercise. However, exceedingly few people can maintain long-term weight loss through calorie restriction because of antagonizing physiological responses, including increasing hunger level and slowing metabolic rate over time.
Contrary to the conventional perspective, recent research has shown that food affects hunger, hormones, and even genetic expression in ways that cannot be explained by consideration of caloric balance alone. For example, energy expenditure decreased by 325 kcal per day among volunteers in a crossover study who consumed a low-fat diet compared with when they consumed a calorie-matched low-carbohydrate diet.6 In other words, the type of calories consumed may affect the number of calories burned. A difference of this magnitude, if persistent, could explain a substantial proportion of the obesity epidemic, even without a change in food intake. In cohort studies, sugary foods, refined grain products, and other high–glycemic load carbohydrates have been associated with weight gain7 and diabetes risk, whereas calorie-dense high-fat foods like nuts, dark chocolate, and olive oil show the opposite relationships.