The application of low-level laser light to the scalp to restore hair growth is not entirely new. But the options for how to get it can affect its effectiveness.

Addressing skepticism, several studies have investigated the efficacy of low-level laser hair loss treatment for hair growth. Researchers Pinar Avci, MD and Gaurav K. Gupta, MC, PhD, et al. published their study in the journal Lasers in Surgery and Medicine in 2015 (“Low-level laser (light) therapy (LLLT) for treatment of hair loss,” August 23 2013), and their findings were encouraging.

“LLLT for hair growth in both men and women appears to be both safe and effective,” say the authors, cautioning that the optimum wavelength and other factors were not identified in their clinical research on human subjects. The bulk of prior research on lasers and hair loss, which found that LLLT consistently stimulated hair growth, was with lab animals.

Which begs the next question: is it better to pursue a LLLT treatment strategy in the home or in a hair loss treatment studio? It depends somewhat on the individual.

• Frequency of application affects results. About three treatments per week of 20-30 minute duration are recommended for most patients. Are you willing and able to visit a studio, at a cost, with that frequency? Alternatively, are you disciplined enough to do it on a regular schedule on your own?
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• Doing it correctly matters. A studio will have a more sophisticated set-up that includes a hood that directs the lasers at the correct distance from your scalp, applying a consistent concentration of light in the right places. A handheld, self-administered LLLT places that responsibility on the individual, aided by a comb that ensures the proper distance; that said, helmet versions are available for home use that control for this.
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• Diode power is important. Most in-studio equipment has 150 to 250 diodes per hood, but advertising for at-home lasers rarely provide this information at online shopping sites. This is likely due to the home versions being at lower power.

Interest in LLLT as a hair-restorer goes back decades when use of the technology with laboratory mice incidentally stimulated hair growth. Over time, studies identified that that laser treatment increases blood circulation in the scalp to stimulate the growth of new hairs in humans. It’s generally most effective at addressing androgenic alopecia, male pattern baldness, where hair follicles are blocked from producing new hairs by the hormone DHT. Hair loss medications (finasteride and minoxidil) otherwise block or diminish the effects of DHT.