Why not everyone succeeds in losing weight, scientists find out

Researchers explained why weight returns after losing it and why the brain resists weight loss. Weight loss is determined not only by food and willpower, but also by complex biological processes. After weight loss, the body actively resists further reduction of fat stores and seeks to return to previous levels. Heredity, body function, environment, as well as stress, sleep, and microbiome play a role. Experts advise not to judge health only by weight and emphasize the importance of a comprehensive approach.

Researchers explained why weight returns after losing it and why the brain resists weight loss. Weight loss is determined not only by the amount of food consumed and willpower, but also by complex biological processes. After weight loss, the body often begins to actively resist further reduction of fat stores and seeks to return to previous levels. This is reported by the Hungarian publication Egészség Kalauz, citing modern research in neuroscience and obesity. Experts emphasize that excess weight is formed under the influence of several factors: heredity, body function, and environmental conditions. Therefore, regaining kilograms after a diet does not always mean a lack of discipline. One explanation is related to evolutionary mechanisms: the ability to store energy as fat tissue helped survive periods of famine. When weight is reduced, the brain perceives changes as a threat and activates mechanisms to restore energy balance, including increasing ghrelin production and reducing calorie expenditure. The body can 'remember' its usual body weight, which explains the yo-yo effect. Experts advise not to judge health only by weight, but to consider physical activity, sleep, diet, and microbiome. Gut bacteria produce short-chain fatty acids that affect metabolism and satiety. It is important to preserve muscle tissue, as it requires energy. Stress raises cortisol and increases the desire to eat sugar and fats, while lack of sleep makes it difficult to regulate appetite. There is no universal weight loss scheme: body weight is influenced by genetics, hormones, age, sleep, psychological state, medications, and living conditions. In the future, personalized treatment for obesity is expected to develop. Even a moderate weight loss of 5–10% of initial weight brings benefits. Modern medicine views obesity as a complex chronic condition requiring a comprehensive approach.