Red light therapy has become the latest ray of hope in the wellness industry. If you listen to wellness influencers, you might think there’s nothing that red light therapy can’t treat. But what’s the science behind the hype?
The claims
On TikTok and other platforms, creators tout red light therapy for skin care, hair growth, joint pain, sleep, longevity, inflammation—even period cramps. From panels to face masks, wands and caps for hair, at-home devices range from about $50 to thousands. But are these devices really doing anything?
“This is the most commonly asked question that I get probably in the last four years,” says Dr. Zakia Rahman, a clinical professor of dermatology at Stanford School of Medicine.
The science
Rahman says it can be challenging to separate science from hype for consumer devices. But the therapy itself—formally called photobiomodulation therapy—does have real science behind it. Red and near-infrared light (longer wavelengths on the visible spectrum) affect mitochondria, the cell’s energy producers. Those wavelengths can stimulate energy production inside mitochondria so cells function better. “We create this energy through that red light and we can use it therapeutically to do things like grow hair, reduce inflammation, or create new collagen in our skin,” Rahman explains.
Scientists noticed red light’s effects decades ago: in the 1960s, a Hungarian researcher who exposed mice to red light found they grew hair instead of cancer. More broadly, light already affects human health—vitamin D production and circadian rhythms—so using light therapeutically is a plausible extension, says Dr. Praveen Arany, a photobiomodulation researcher at the University at Buffalo.
The applications
For cosmetic uses like hair and skin, benefits take time—months of consistent use, typically several times a week. Don’t expect dramatic overnight changes.
Red light therapy has been shown to help treat androgenetic alopecia (pattern hair loss). “It does help,” says Dr. David Ozog, chair of dermatology at Henry Ford Health. You can objectively see improvements in hair quality and number, but results depend on how advanced the hair loss is. “It’s not going to take you from being bald to being a Chia pet,” he says.
For skin, evidence shows red light can improve fine lines and wrinkles, though effects are modest compared with more aggressive dermatologic procedures like laser peels. “It may be helpful for some of the surface changes on the skin, for the superficial changes, but not for deep wrinkling,” says Dr. Elma Baron, a dermatologist at Case Western Reserve. There’s also evidence it can help with acne. Ozog ranks red light below proven topical treatments such as retin A and vitamin C or in-office laser treatments.
Beyond cosmetics, there’s solid evidence for several medical uses. Ozog coauthored a 2025 consensus review finding the therapy effective for pattern hair loss, ulcers, peripheral neuropathy, several types of ulcers, and acute radiation dermatitis. Clinical guidelines recommend light therapy to prevent and treat oral mucositis (painful mouth ulcers and inflammation) common in cancer treatments. Red and infrared light can calm that inflammation, Ozog says. There’s also evidence it can reduce pain and modestly speed healing from recurrent cold sores.
Recently, the FDA has authorized marketing of some red light devices for treating dry age-related macular degeneration and for the temporary relief of pain from fibromyalgia. For many conditions, experts view red light as a complementary therapy rather than a first-line treatment. “In some areas we have reached the highest level of evidence. In the other areas, it remains more anecdotal,” says Arany.
“The Wild West” of products
When buying a device, “buyer beware” applies. Many consumer devices are FDA cleared for safety but not proven effective. Ozog says he has tested products that didn’t emit enough energy to have an effect. He advises looking for independent safety certification from recognized labs (like Intertek or UL) and separate third-party optical testing for wavelength and irradiance.
Some online devices don’t emit the correct wavelengths. Different wavelengths and treatment times are effective for different concerns: for skin rejuvenation, evidence suggests wavelengths from about 620 to 1,072 nanometers can work, with longer wavelengths penetrating deeper. For pattern hair loss, wavelengths of roughly 630 to 800 nanometers have been reported as effective. Choose a device aimed at your specific concern.
Other caveats and potential concerns
“Red light is something that has a pretty high safety margin,” says Baron, but there are caveats. Protect your eyes when using a red light device—prolonged exposure to red or infrared light could harm the retina. Many devices include goggles. Some people report headaches after use.
People prone to melasma or other pigment disorders should be cautious. Visible light can stimulate pigmentation; shorter wavelengths like blue light carry higher risk than red, but overuse of red light may still worsen pigment issues, Rahman warns.
Bottom line
Red light therapy shows promise for many aspects of health, but evidence varies by use. It’s not magic. “Just shining light on you is not going to make you superhuman in any way,” Arany says—you still need healthy habits like good nutrition, exercise and sleep.
If navigating devices feels overwhelming, a simple alternative is to get outside in the morning or early evening, when the environmental ratio of red light is more favorable. “You’re actually getting more of that red light in the morning, that’s why you get that coloration of the sky,” Ozog says. “Drink your coffee, listen to the birds, get that morning light and start your day off right.”