Study claims obesity caused by picking wrong foods, not eating too much

Despite years of calories-in, calories-out dieting advice, obesity levels are increasing in many countries, raising public health concerns. A newly published perspective piece notes that the root cause of obesity — and perhaps key to addressing the problem — may not be as simple as overeating, but rather the types of food that people are often consuming.

According to the new perspective, tackling obesity and achieving long-term weight loss may involve addressing what the researchers call the carbohydrate-insulin model, which addresses the consumption of high glycemic, processed, and rapidly digested carbohydrates common in modern diets.

Of note, eating these highly processed carbohydrates triggers the body to produce the hormone insulin, which in turn suppresses glucagon secretion. This hormone change 'tells' the body's fat cells to store more calories, leaving fewer for use elsewhere in the body. The brain, then, ramps up feelings of hunger as it perceives a lack of energy available to metabolically active tissues.

In addition to the overeating that may then result from this hormonal process, the body's metabolism may also slow down as a way to conserve what it perceives as limited amounts of energy, throwing someone into a cycle of hunger, overeating, and packing on the pounds.

According to the American Society for Nutrition, this latest work represents the "most comprehensive formulation" of the carb-insulin model thus far. The perspective suggests that by encouraging people to focus on the carbohydrate-insulin model rather than the energy-balance model, society may be better able to address the obesity epidemic.