The weight loss and very restrictive diets They were once again under analysis after new studies showed that eating little for long periods can generate effects that end up making it difficult to sustain a sustained decrease in body fat.
Different specialists began to observe something that often appears in people who reduce calories suddenly: the body changes part of its energy expenditure and adaptation mechanisms.
The situation is usually seen especially in prolonged diets, where fatigue, Constant hunger and loss of muscle mass They begin to mix with a brake on weight loss.
For years, much of the diets popular ones were based on a fairly direct logic: the less you eat, the faster you lose weight. However, that idea began to be revised by research on nutrition, appetite and ultra-processed foods.
The doctor and researcher Fatima Cody Stanford, obesity specialist at Massachusetts General Hospital and Harvard Medical Schoolmaintains that the problem should not be looked at only from the quantity of calories, but also from the quality of the food.
In controlled feeding studies, diets higher in ultra-processed products led people to consume more total calories, even when the meals were designed to be nutritionally similar.
Barbara Rolls, professor of nutritional sciences at Penn State and researcher at the Laboratory for the Study of Human Ingestive Behaviorhas been working on energy density for years. Their approach suggests that many people regulate what they eat by the volume of the plate, not by the exact number of calories.
Therefore, a small portion of bills, snacks or highly processed foods can provide as many calories as a much larger plate with chicken, vegetables and some starch.
For its part, Traci Mann, psychologist and director of the Health and Eating Lab at the University of Minnesotaexplains that the problem is not only due to willpower. In environments where soft, tasty, high-calorie and fast-consuming foods are abundant, the body is exposed to signals that push it to continue eating.
For this reason, the specialists cited by National Geographic suggest that “eating less” can fail when it translates into small dishes that are not very satiating and difficult to maintain.
What happens in the body when the restriction is too aggressive
One of the most studied changes has to do with the basal metabolism. The body needs energy even at rest to maintain basic functions such as breathing, body temperature and brain activity.
When the intake falls too low for a long time, the body tries to adapt to spend less.
That’s why some people begin to notice more fatigue, difficulty training, or feeling frequently cold during extreme diets. The loss of muscle mass also has a significant influence.
He muscle consumes more energy than other tissues and helps sustain part of the daily caloric expenditure. If you lose too much, your body ends up needing fewer calories.
There appears one of the most common problems of very fast diets: They generate a strong initial decline, but then the process becomes increasingly difficult to sustain.
Why specialists recommend more sustainable approaches
Instead of extreme cuts, many nutritionists they started to prioritize moderate deficits and sustainable strategies over time. The idea is to generate healthy weight loss without causing such an aggressive impact on metabolism and muscle mass.
There, factors that many diets previously left in the background become important: sufficient protein, strength training, rest and daily physical activity. Also The view on the speed of descent changed quite a bit.
Several specialists maintain that Losing weight too quickly can increase your chance of regaining weight later. That is why many current strategies aim at slower but sustained progress. Experts also emphasize that the sustained weight loss usually depends more on habits that can be maintained for months than extreme changes applied for a short time.
