1. Physical reasons: high basal metabolic rate

There are two main hormones that affect people's fat and thin, the hormones that can make people thinner are adrenaline and thyroxine, which are in charge of metabolism; The hormone that can make you fat is insulin. When the skinny hormone in the human body is lower than the fat hormone, the human body will be biased towards the fat-prone physique. When the hormone in charge of metabolism in the human body is secreted more, people tend to be prone to thin physique. People who are prone to thin constitution have a high basal metabolic rate, and a large part of the calories they consume are used for basal metabolism.

2. High physical activity

We will find that coaches and athletes eat much more than normal, but they don't gain weight. This is because they are physically active. People gain weight because they consume far more calories than they consume. People who are physically active consume more calories, and even if they consume more calories, they are not prone to gaining weight.

3. Unbalanced diet

The body's energy mainly comes from three sources of nutrients: carbohydrates, fats and proteins. Among them, carbohydrates and fats are more important raw materials for energy. If you eat a lot of foods, but these foods are more nutritious than protein and less carbohydrates and fat, then you may not have the illusion that you will not gain weight no matter how much you eat. This nutritional unbalanced diet structure is easy to cause malnutrition, and it is recommended that some people who want to lose weight should not try such a weight loss method with a fluke mentality.

4. Cause of the disease

Sudden weight loss and not gaining weight no matter how much you eat may be a sign of some diseases. Hyperthyroidism, diabetes, cirrhosis, chronic gastrointestinal diseases, etc. are all accompanied by symptoms of weight loss. People who don't get fat no matter how much they eat should pay attention to see if they are due to illness.