Red Light Therapy for Hair regrowth

Thinning and hair loss affects millions of men and women. Red Light Therapy is scientifically proven and FDA approved for regrowing hair. The predominant wavelength I have seen used in studies is around 650 nm.

Originally this research was performed only using low-level laser therapy (LLLT). However, today various manufacturers offer hair restoring skull caps fitted with dozens of laser diodes and standard LEDs.

The advantages of this therapy are that it applies to both men and women of all races, and there aren’t any reported adverse side effects.

One of the first effects observed by Mester in 1968 was the regrowth of hair around a wound he treated with laser light. The wavelength of light used by Mester in his original research was 694nm.

As discussed in my other red light therapy articles, the light stimulates cells in the same manner across the body. In this case, the light directed toward the scalp stimulates the cells in the hair follicles to grow. The exact process by which this happens is not known. One theory is that light acts as a vasodilator and allows more blood to the hair follicle. This is believed to be how, at least in part, how the over the counter drug Minoxidil works to restore hair.

Modern hair regrowth devices use both standard LEDs and Laser LEDs. The laser LEDs provide a pinpoint light source, and the standard LED will give a diffuse light source. The combination of radiance is believed to optimize the stimulation of the hair follicles.

Preliminary studies with mice illustrated the biphasic effect of photobiomodulation. When mice were treated with 1J/cm², they showed significant hair regrowth (above baseline) in three weeks. However, when the light dosage was increased to 5J/cm², hair growth was significantly decreased (below baseline) in hair growth¹.

The light dosages illustrate the biphasic nature of photobiomodulation therapy, where too much light is worse than too little. For more information, please read my article on Red Light Therapy Dosages.https://john-iovine.medium.com/regrow-thinning-hair-using-red-light-therapy-4fc16614f013