The reason why hair breaks easily is mainly seen in ringworm and nodular brittle hair, and it may also be related to nutritional deficiency and improper care and other factors. 1. Tinea capitis: a disease caused by infection of the scalp with ringworm bacteria, which affects the hair follicles and the hair shaft, making hair loss and hair breakage easy to occur in the clinic. 2. Nodular brittleness: it is a kind of hair structure defect caused by many factors, in the clinic, it is mainly seen in the multiple nodules on the hair shaft, and the hair becomes brittle and easy to break, in which women are the most popular people with this disease. 3. Others: Frequent inappropriate hair coloring and perming will affect the hair quality, making the hair brittle and easy to break. Excessive dieting and nutritional deficiencies can also lead to dry and brittle hair. As there are many factors affecting the hair quality, you need to consult a doctor for specific cases.