1. Nutritional imbalance: If the intake of certain important nutrients in the diet is insufficient;
2. Special populations: Some individuals require additional nutritional supplements due to special circumstances;
3. Certain diseases or conditions:Certain diseases or conditions can cause the body to be unable to fully absorb or utilize nutrients;
4. Special dietary habits: Some people may have dietary preferences, restrictive diets (such as vegetarians), or Unable to obtain sufficient nutrition due to special dietary habits.