Slow hair growth in men may be related to genetic factors, malnutrition, lifestyle habits, severe anemia, and so on. 1. Genetic factors: If parents have slow hair growth, they may pass on the relevant genes to their children, resulting in slow hair growth. 2. Malnutrition: When the body is malnourished, due to the lack of vitamins and trace elements related to the growth of hair follicles, slow hair growth and hair thinning may occur. 3. Lifestyle habits: If men are under long-term mental stress, overworked, and often stay up late, it may lead to slow hair growth. 4. Severe anemia: when men have severe anemia, it will easily lead to protein deficiency and keratin scarcity of hair shaft, causing slow hair growth in men. If men have slow hair growth, it is recommended that they go to the hospital in time to get a clear diagnosis and follow the doctor’s instructions for treatment.