From the Guidelines
Low-level laser therapy (LLLT) with a wavelength of 308-nm, as used in excimer laser treatment, is the most effective wavelength for hair growth stimulation, as evidenced by a study published in the British Journal of Dermatology 1. The use of LLLT for hair growth has been explored in various studies, with the 308-nm excimer laser showing promising results in treating alopecia areata.
- In a study of 18 adults with alopecia areata, 42 patches were treated twice weekly for 12 weeks with a 308-nm excimer laser, resulting in regrowth in 17 patches 1.
- Similar results were observed in a study of nine children with alopecia areata, with a 60% response rate to excimer laser treatment 1. While other wavelengths, such as infrared diode laser, have also been used to treat hair loss, the 308-nm excimer laser has shown significant efficacy in promoting hair growth.
- The exact mechanism of LLLT in promoting hair growth is not fully understood, but it is thought to increase cellular energy production, improve blood circulation, and reduce inflammation in the scalp.
- For optimal results, consistent use of LLLT devices, such as those emitting a 308-nm wavelength, is recommended, although the exact treatment protocol may vary depending on the individual and the type of hair loss being treated.
From the Research
Wavelength of Light for Hair Growth
- The wavelength of light used for hair growth is in the visible red light spectrum, specifically around 655 nm 2 and 650 nm 3.
- Studies have shown that low-level laser therapy (LLLT) with a wavelength of 655 nm significantly improved hair counts in males with androgenetic alopecia 2.
- Similarly, 650 nm red light stimulation has been found to promote hair growth and delay the transition of hair cycle from anagen to catagen in vitro 3.
- Other studies have also discussed the use of LLLT as a treatment option for androgenetic alopecia, highlighting its potential as a non-invasive and effective therapy 4, 5, 6.