Red Light Therapy: Scientific Evidence Behind the Celebrity Trend
International pop star Katy Perry uses red light therapy tools. So do the Kardashians and actresses Jessica Alba and Julianne Moore. Many people now regularly don glowing masks, wave red light wands over their face, and sit or lie in rooms with LED panels to help improve their skin and receive other health benefits. Treatments and products can cost hundreds of dollars, and the global market is projected to surpass $1 billion by 2030, according to Research and Markets.
The Science Behind Photobiomodulation
But how do the purported benefits of red light therapy—also known as photobiomodulation—align with the science? Well, maybe more than you might believe. "I thought this was just the latest fad to get people to spend their money," Dr. Rachel Reynolds, interim chair of the Department of Dermatology at Harvard-affiliated Beth Israel Deaconess Medical Center, said in a statement. "But there's legitimate medical literature supporting it," she noted.
The literature is based on science that’s been around for decades. Photobiomodulation research became popular after NASA conducted red light experiments on plants in space in the 1990s, according to Nature.
How Red Light Therapy Works
The non-invasive treatment uses near-infrared light from LED lights or lasers to affect the body’s cells, stimulating mitochondria: the main energy source in cells that support cell growth and function. It can be used to increase collagen production, improve acne and other skin conditions, reduce redness and inflammation from sun damage, promote healing, and relieve pain by decreasing inflammation through enhanced cell production, according to the MD Anderson Cancer Center in Texas.
In a 2005 study, the majority of 90 patients who received eight treatments over a month reported softer and smoother skin, less redness, and lighter dark spots, as noted by the American Academy of Dermatology Association.
FDA-Cleared Applications and Hair Regrowth
The U.S. Food and Drug Administration has cleared several red light devices for at-home use to treat skin, using a less rigorous evaluation process than full approval. The agency has also cleared red light caps and helmets to treat thinning hair, as the light may stimulate hair follicles.
"The dilation of blood vessels enables more blood and nutrients to reach the hair follicles. Used consistently over multiple months, red light has been shown to regrow thinning hair. But it should also be noted that when the person stops applying red light, the effects stop," explained Dr. Zakia Rahman, a clinical professor of dermatology at Stanford Medicine. She suspects this effect on blood vessels likely produces other dermatological benefits.
Beyond Skin: Pain Relief and Cognitive Benefits
In cancer patients, the therapy is used to treat pain and mouth sores, MD Anderson said. "It can also help release neurotransmitters such as endorphins, which are natural painkillers," according to Brown Health. The therapy may even improve cognition in people with dementia.
Near-infrared light from helmets can penetrate the skull, exposing the brain to its effects, notes UCLA Health. A 2021 study found that just six minutes a day for two months improved cognition in dozens of patients with mild-to-moderate dementia.
Limitations and Unsupported Claims
Still, not all purported benefits have data to back them up. Rahman and Stanford Medicine say claims about uses for dementia, erectile dysfunction, and chronic pain lack "any scientifically validated results." "While hair regeneration and wrinkle reduction have fairly robust evidence to support the use of red light therapy, other applications, such as improving athletic performance, lack data," the school says.
Safety and Practical Considerations
Red light therapy appears safe when used as directed, with mild side effects like temporary pain or irritated skin. However, improper use could lead to serious problems, such as retina damage from lasers or skin burns. People should seek FDA-cleared devices or consult a dermatologist for stronger treatments. To see results, multiple sessions over weeks or months are necessary.
"Start with only a few minutes, working your way up to about three times a week," advised Dr. Mary Stevenson, a dermatologist and skin cancer surgeon at NYU Langone Health, in an interview with TODAY.com.
The bottom line is that while years of research exist, red light therapy is still emerging, and more studies are needed to support most uses, according to the Cleveland Clinic. "Most researchers say results so far look promising, but that more quality studies with larger numbers of people are needed," the clinic noted.
