"The combination of active ingredients containing caffeine keeps the hair root awake and counteracts premature hair loss. The active ingredients run along the hair shaft and form an active ingredient depot that lasts up to 24 hours. The hair root is strengthened and hereditary hair loss is prevented. Leaves a fresh tingling sensation on the scalp. Ideal for men who do not wash their hair every day.the caffeine complex activates the hair root, prolongs the growth phase and improves hair growth.niacin and zinc salts strengthen hair growthmenthol refreshes the scalpApply in the morning and after each hair wash with the dosage tip directly to the towel-dried scalp and massage in. DO NOT RINSE!Scientific:In 80% of all cases, it is """"androgenetic alopecia"""" that causes concern for men: Hereditary hair loss due to a hypersensitivity of the hair roots to the hormone DHT testosterone. On the one hand, testosterone makes the beard hair grow, on the other hand, it weakens correspondingly predisposed hair roots in the scalp. They die prematurely because testosterone cuts off their energy supply.With a combination of active ingredients containing caffeine, Alpecin has succeeded in stopping this negative testosterone effect and thus effectively combating the cause of hereditary hair loss.To understand how caffeine works, we need to take a closer look at the growth cycle of a hair: Normally, the hair root is active for up to 8 years (growth phase) and then goes into a resting phase. The root lets go of the hair, it falls out - without the threat of hair loss. Because after that a new growth phase begins again - about 14 times, then it dies completely.In hereditary predisposition, DHT testosterone prevents the formation of the energy messenger c-AMP, which is necessary for the metabolism of the hair root. This shortens their growth phases and their lifespan ends too soon. When more and more roots die in this way, baldness occurs.The active ingredient in Alpecin, which contains caffeine, shields the hair roots from the testosterone attack. The growth phases become longer, which means: hair growth into old age becomes possible.The effectiveness of caffeine against testosterone is confirmed by current dermatological studies by the University Hospitals of Hamburg Eppendorf and Jena."