Researchers from some top universities like Harvard, Weill Cornell Medicine and Duke University make a case that mainstream nutrition advice has misunderstood how people gain and lose weight based on calories alone, arguing that hormones like insulin also play a key role.
Experts say high-carb diets are increasing obesity
The current idea of weight gain or loss is based on how much energy one consumes in the form of calories from food. If a person eats more than they burn during the day, they will gain weight. If they eat less than what they burn, they will lose weight. The concept is called calorie in, calorie out theory (CICO).
The alternative weight loss approach according to researchers is the carbohydrate-insulin model of obesity, which suggests that hormone levels are responsible for how we either store or burn off body fat.
For example, a diet high in processed carbohydrates can cause a spike in blood sugar levels and prompt the body to release insulin. High levels of insulin over time can make the body less sensitive to the hormone, forcing it to release more to keep the blood sugar stable. The theory says that high levels of insulin prompt the body to store more body fat, even without an excess of calories and disrupt the hunger cues, creating a vicious cycle of metabolic disruption.
The carb-insulin model of obesity isn’t new and has been repeatedly suggested by advocates of the low-carb and ketogenic diet.
Some experts say processed foods also play a major factor.
Calories still play a part in weight loss
Though insulin plays a role in fat storage, there is no study that claims that it matters more than calories intake.
Evidence suggests that processed foods and refined carbohydrates contribute to obesity. Other factors like calorie density, the ratio of carbs to other macronutrients like fat and protein and food environment all play a role in how one loses weight.