I’ve been seeing red lately.

No, not because of my normal, touchy, moody nature. More because of the prevalence of something called Red Light therapy, or photobiomodulation, thank you very much. Red light therapy (or RLT) uses low-wavelength red and near-infrared light to penetrate the skin and stimulate cellular activity. It essentially “boosts the metabolism” of your cells by energizing your mitochondria—the powerhouses of your cells—to produce more energy.

Prevalence. Photobiomodulation. Mitochondria. Literacy is SO sexy, neh?

The word for it might be new, but the studies that evaluated the effects of red light on biology date back to the 1960s. Before red light gained a reputation in the beauty industry, dermatologists used it for early-stage treatment of precancerous and early, thin skin cancers. Red light applied at a specific wavelength in conjunction with a topical drug kills skin cells, a type of treatment called photodynamic therapy. (Note, red light, alone, does not destroy skin cancer.) When applied to damaged or diseased skin cells, such as cancer cells, those cells die off and allow for the growth of new skin.

More recently the tools to harness its potential benefits have become more available online as well as in spas, gyms and dermatology clinics. While it has gained a reputation as a multi-faceted ray of wellness, with claims that it can treat conditions ranging from aging skin to erectile dysfunction, what does the research say? What are some of the benefits of RLT?

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 substantial data. Since red light devices come in a variety of shapes and sizes, have different potencies and prescribed time of use, as well as extreme variation in costs, measuring their comparative effectiveness can be like comparing apples with oranges. However, according to science, red light certainly isn’t bogus. Red light can be tailored to use specific wavelengths to target tissue and stimulate an effect within tissue.

Hair growth and skin care: Studies have shown that red light penetrates the skin at shallow depths and stimulates follicle growth. There’s evidence that the light causes vasodilation, a widening of blood vessels. That dilation enables more blood and nutrients to reach the hair follicles. Used over multiple months consistently, red light has been shown to regrow thinning hair. But it should also be noted, when the person stops applying red light, the effects stop.That vasodilation ( I promise, that’s the last time I’ll say “vasodilation”) is also likely the mechanism for other dermatological effects of red light, such as wrinkle reduction. Hundreds of studies documenting the impact of red light in a clinical setting have reported a range of outcomes, including how different wavelengths of red light change the inner workings of cells and show how red light plumps up skin features in human participants through an increase of collagen production. So yeah, for as long as you use RLT, you enjoy these benefits.

VASODILATION!!! Sorry, had to…

Wound healing, scarring: Some preliminary studies pointed toward potential for accelerated skin and tissue healing, depending on the wavelength of light, duration and frequency of treatment. But the studies didn’t show strong and consistent success, leaving a question mark in the minds of dermatologists. In a recent study conducted by researchers at the University of California, Irvine, in which they performed a surgical eyelid lift, and treated one group of patients with red light. In the words of one of the researchers “It was slightly more than a coin toss, but not by much, that the red light-treated group did better. But it was not statistically significant,” . In another paper documenting healing from the same surgical procedure, results differed. In that study, the red light-treated scar healed in half the time, compared with the nontreated side in the same patient, which is pretty significant. At six weeks, however, both sides of the eye had healed completely, with no differences. This result does suggest that in the first few weeks during the first phases of wound healing there could be benefit for red light. Very interesting results and these effects deserve further study, but for now, the data is somewhat conflicting and there are a lot of caveats.

Athletic performance, sleep, etc.: Sleep expert Jamie Zeitzer, PhD, and sports physician Michael Fredericson, MD, say the data to support red light efficacy for either is at best, speculative. In theory, red light could be used to stimulate muscle and tissue healing in the same way it’s used for wound healing, as muscle growth technically requires small lesions in the tissue that eventually heal and result in larger muscles. In theory.

There are some more exotic claims about red light uses: erectile dysfunction, chronic pain, even dementia. While interesting avenues for future exploration, none have any scientifically validated results.

At home versus the clinic: Red light therapy, particularly for hair growth or skin rejuvenation, delivered in a clinic will almost always be more powerful than any at-home device. But even red light treatments in a dermatology clinic aren’t a sure bet — their effectiveness can vary, depending on the wavelength of red light and the duration and frequency of treatment, which is largely unknown when people buy tools for use at home. There is still more research to be done. Whether dabbling at home or receiving treatment in a clinic, the risk of dangerous side effects is generally low. Some devices are cleared by the Food and Drug Administration, but that focuses mainly on safety, not effectiveness.

My final words on red light therapy? Stay tuned and dip your toes in if you like. There is real scientific evidence to back some uses in a clinical dermatology setting, particularly for hair growth and skin rejuvenation. But it’s early days, and more research will give a clearer picture of what other benefits RLT provides.

Beneficial? Yes. A universal panacea? Maybe not.

At least IMHO…

T L,

B.T.