The causes of hair loss at the age of twenty are: 1, genetic genes; 2, long-term late night, mental stress, or excessive thinking endocrine disorders and hair loss; 3, weakness of the spleen and stomach leading to lack of qi and blood, lack of nutrition; 4, seborrheic dermatitis, folliculitis, fungal infection, etc. so that the hair roots break down and cause; 5, environmental diet; 6, autoimmune factors, such as vitiligo, thyroid disease, etc.. Need to identify the cause, active symptomatic treatment, you can should side berry leaf, He Shou Wu boiled water to rub the scalp.