Low-Level Laser/Light Treatment (LLLT)

Photobiostimulation, the mechanism by which LLLT is thought to exert its effects on hair growth, is poorly understood. Some proposed mechanisms include causing changes in cellular chemical reactions, modulation of the inflammatory response by reducing inflammatory chemokines, increasing blood flow through the release of nitrous oxide from cytochrome c oxidase in mitochondria, and working to stimulate resting hairs into anagen. In other words, it is believed that the light of specific wavelengths causes a cascade of chemical reactions that stimulate the stem cells of hair follicles resulting in hair growth and possibly increasing blood flow.

The FDA has approved many LLLT devices for use in hair loss. However, to date, no large-scale studies exist that have shown them to have any statistically significant benefit for hair loss treatment.