3) Hormones: The Role of DHT Dihydrotestosterone (DHT) is a hormone in the body that plays a major role in hair loss. In people with pattern baldness, DHT binds to hair follicles and causes them to shrink. Over time, this prevents the follicles from producing strong, healthy hair. The result? Hair becomes thinner, weaker, and more likely to fall out, especially along the hairline.