Why do I gain weight in winter even when eating the same amount of food?

Weight gain during winter despite the same food intake is mainly due to factors such as reduced basal metabolic rate, decreased physical activity, changes in diet structure, inadequate water intake, and fluctuations in sleep quality, all of which lead to reduced calorie expenditure and fat accumulation. If body weight increases rapidly within a short time and is accompanied by fatigue or edema, prompt medical evaluation is recommended.

1. Reduced Basal Metabolic Rate: In cold winter temperatures, the body adjusts its metabolism to maintain core temperature. However, in prolonged cold environments, the body reduces energy expenditure to conserve heat, resulting in a lower basal metabolic rate. Even with unchanged food intake, excess calories are more likely to be stored as fat.

2. Decreased Physical Activity: Cold weather reduces people's willingness to go outdoors, leading to fewer daily steps and less frequent exercise. This significant drop in overall calorie expenditure creates a caloric surplus, causing gradual weight gain.

3. Changes in Diet Structure: In winter, people tend to prefer warm, high-fat, and high-sugar foods such as hot pot, stewed dishes, and desserts. These foods have a high calorie density; even if portion sizes are smaller, total calorie intake may still exceed requirements, increasing the risk of obesity over time.

4. Inadequate Water Intake: With less sweating in winter, people often neglect hydration. Dehydration can slow down metabolic efficiency and impair fat breakdown. Additionally, thirst may be mistaken for hunger, leading to unnecessary snacking and increased calorie intake.

5. Fluctuations in Sleep Quality: Shorter daylight hours in winter may disrupt circadian rhythms, resulting in insufficient or poor-quality sleep. This affects the secretion of leptin (a hormone that regulates appetite), increases hunger, and contributes to weight gain.

To maintain a stable weight in winter, consider indoor exercises such as yoga or jump rope, include more vegetables and lean meats in your diet, ensure adequate daily water intake, and avoid staying up late. Maintaining regular作息 (daily routines) and moderate physical activity can help manage weight effectively.