Red light therapy can reduce pain in a variety of contexts, especially conditions involving joint pain, including knee osteoarthritis,[1] lower back pain,[2] and neck pain.[3] There is also preliminary evidence that red light therapy can reduce pain in fibromyalgia,[4] tendinopathy,[5] rheumatoid arthritis,[6] and headache,[7] as well as during hip surgery recovery.[8]
Red light therapy has been shown to promote hair regrowth in people with hair loss due to androgenic alopecia, with effects seen in both men and women.[9][10] In these studies, the scalp is directly exposed to red light, usually in the 650 to 660 nm range.
Red light therapy has been found to be beneficial for childhood myopia (nearsightedness), slowing its progression and even preventing its occurrence.[11][12][13] Red light therapy may also be helpful for other eye conditions (e.g., macular degeneration, cataracts), but research is still too limited to be certain of its effectiveness.[14][15][16]
Preliminary evidence suggests red light therapy can improve cognitive function in people with dementia[17] and possibly in healthy people as well.[18]