In normal people, 5α-reductase is in a state of dynamic equilibrium and does not increase all the time. 5α-reductase is a membrane protein in target cells, mainly found in microsomal and nuclear membranes, and is a reductase enzyme that catalyzes the conversion of testosterone to the more active dihydrotestosterone. Under physiologic conditions, 5α-reductase does not always increase. Too much 5α-reductase may lead to an increase in dihydrotestosterone, causing hair loss in men, hirsutism in women, acne, and benign prostatic hyperplasia, etc. Too little 5α-reductase may lead to 5α-reductase deficiency, which is a hereditary disease. If 5α-reductase is abnormal, it is recommended to go to a regular hospital for consultation, and to get a clear diagnosis and treatment under the guidance of a professional physician.