Severe hair loss in summer may be related to bad living habits, or it may be caused by androgenetic alopecia, folliculitis and other reasons. 1. Bad living habits: In summer, due to the hot weather, the existence of bad living and eating habits, such as staying up late, eating barbecue at night, drinking alcohol, etc., may lead to an increase in the sebaceous glands secreted by the organism, thus causing severe hair loss. 2. Androgenetic alopecia: it may be related to genetic factors, excessive secretion of androgens and other factors, which may induce androgenetic alopecia, and it will lead to more serious hair loss. 3. Folliculitis: in the summer due to the high temperature is easy to breed germs, if you do not pay attention to the scalp area of the hygiene, it is easy to cause scalp follicles by bacteria, infection, induced folliculitis, resulting in follicle damage, it may cause serious hair loss in summer. Hair loss in summer may also be related to other factors, it is recommended to consult a doctor as soon as possible.