TLDR Hair loss is mainly caused by a testosterone byproduct, and hair restoration surgery uses hair from the back and sides of the scalp.
The document from 16 years ago discussed the cause of permanent hair loss, largely attributed to the testosterone metabolite, dihydrotestosterone (DHT). DHT was found to "turn off" genetically sensitive follicles, typically located in the frontal or frontoparietal scalp, leading to what is known as male pattern baldness. The follicles in the occipital and parietal regions of the scalp were identified as the donor areas for restoration surgery. It was noted that a balding person typically had between 5000 and 6000 follicles available for hair donation, having lost up to 30,000 follicles.
8 citations,
September 2010 in “Journal of Men's Health” Androgenic Alopecia, a common hair loss condition, can be effectively treated with finasteride and other treatments.
8 citations,
October 1988 in “Clinics in Dermatology” Current research explores hair growth drugs, while future research aims for personalized treatments.
May 2023 in “Experimental Dermatology” Male pattern hair loss may be linked to the developmental origins of hair follicles.
100 citations,
April 2010 in “Expert Opinion on Pharmacotherapy” Hair loss in men treated best with early medication or transplant, new treatments researched.
416 citations,
September 1997 in “Journal of Investigative Dermatology” People with hair loss have more androgen receptors and enzymes in certain follicles, with men and women showing different patterns.
5 citations,
February 2011 in “Expert Opinion on Drug Discovery” We need better treatments for hair loss, and while test-tube methods are helpful, they can't fully replace animal tests for evaluating new hair growth treatments.
