Low level laser therapy stimulates hair follicles to reenter the
growth phase from dormancy and prolongs the growth phase of the hair. It
helps in preventing premature aging of the follicle. It also increases the
strength of hair by increasing the anchoring filaments in hair.
The hair growth cycle consists of three phases: growth (anagen phase),
resting (telogen phase) and shedding (catagen phase). Hair loss in
androgenetic alopecia depends on a testosterone derivative in the skin,
dihydrotestosterone (DHT). Low-level laser therapy is believed to increase
blood flow in the scalp and stimulate metabolism in catagen or telogen
follicles, resulting in the production of anagen hair. The photons of light
act on cytochrome C oxidase leading to the production of adenosine
triphosphate (ATP)which is converted to cyclic AMP in the follicle cells
releasing energy and stimulating metabolic processes necessary for hair
growth. Release of nitric oxide from cells leads to increased
vascularisation to the scalp distributing nutrients and oxygen to the hair
roots. It even prevents the excessive build-up of Dihydrotestosterone(DHT).
