Sept. 13 (UPI) — Overeating has traditionally been linked to obesity, but researchers say the real culprit is a diet high in processed sugars and carbohydrates, according to a commentary published Monday by the American Journal of Clinical Nutrition.
These foods cause hormonal changes in the body that alter metabolism, leading to a rise in fat storage and, thus, weight gain, the researchers said.
Consumption of food containing highly processed carbohydrates forces the body to produce more insulin, a substance used to digest sugar.
This, in turn, signals fat cells to store more calories, leaving fewer available to provide energy to muscles.
As a result, the brain thinks that the body is not getting enough energy and generates feelings of hunger, the researchers said.
“Reducing consumption of the rapidly digestible carbohydrates that flooded the food supply during the low-fat diet era lessens the underlying drive to store body fat,” study co-author Dr. David Ludwig said in a press release.
“As a result, people may lose weight with less hunger and struggle,” said Ludwig, an endocrinologist at Boston Children’s Hospital.
More than 40% of adults in the United States meet the criteria for obesity, or being severely overweight, the Centers for Disease Control and Prevention estimates.
This places them at increased risk for heart disease, stroke, type 2 diabetes and certain types of cancer, according to the agency.
Guidelines from the U.S. Department of Agriculture recommend that adults who want to lose weight should “reduce the number of calories they get from foods and beverages and increase the amount expended through physical activity.”
However, this approach is based on the idea that weight gain is caused by consuming more energy than is expended, and it does not explain the biological causes of weight gain, Ludwig and his colleagues said.
And, despite decades of public health messaging urging people to eat less and exercise more, rates of obesity and obesity-related diseases continue to rise, they said.
“During a growth spurt, for instance, adolescents may increase food intake by 1,000 calories a day,” Ludwig said.
“But does their overeating cause the growth spurt or does the growth spurt cause the adolescent to get hungry and overeat?” he said.
Instead, he and his colleagues argue for a new approach to weight management called the “carbohydrate-insulin model.”
In contrast to what they call the energy balance model, the carbohydrate-insulin model holds that excessive consumption of foods high in sugar, or glycemic content, such as highly processed, rapidly digestible carbohydrates, causes weight gain.
Widespread adoption of the carbohydrate-insulin model over the energy-balance model would have radical implications for weight management and obesity treatment, the researchers said.
Rather than urge people to eat less, a strategy which usually does not work in the long run, the carbohydrate-insulin model suggests another path that focuses more on what we eat, avoiding processed foods, Ludwig said.