What Science Says About Red Light Therapy

You may have noticed that red light therapy is trendy, but does it really work?

We independently evaluate all recommended products and services. If you click on links we provide, we may receive compensation.

Disclaimer: Just so you know, if you order an item through one of our posts, we may get a small share of the sale.

If you’ve got your finger on the pulse of the skincare industry, you’ve likely heard of red light therapy as a cure for many ailments: fatigue, acne, fine lines, anxiety, run-of-the-mill injuries, and even cancer. And despite the fact that the skincare industry seems to try and discard trends every single day, light therapy—particularly red light therapy—has had notable staying power. Just the other day, a friend posted an Instagram story in which she was sitting in a sauna built for one with red lights shining down on her as she bobbed her head to one of her Spotify playlists (because of course an aux cord was included in said sauna). Red light therapy is definitely still trendy. But people also really believe it helps their skin, their sleep, and even their busy minds in need of stress relief. We spoke to dermatologist Rhonda Klein, MD, about the red light therapy claims and how she uses red light therapy in her practice. If you’re wondering what red light therapy it is or how it could possibly work, read on.

What is red light therapy?

Red light therapy, also known as low-level laser light therapy (LLLT) or biostimulation (BIOS), is the name given to a large range of therapies that use certain wavelengths of light to promote healing, improve skin tone, and enhance circulation. Red light therapy is said to be effective for pain management, acne treatment, and the healing of certain sports injuries, among other applications. Those are some pretty big claims, so we decided to look into the science of red light therapy. Admittedly, we’re pretty skeptical of anything that claims to cure so many things, especially when, at first glance, it boils down to spending time under a certain lightbulb. That said, while red light therapy isn’t necessarily a miracle treatment, it’s not entirely bogus either.

How does red light therapy work?

While “Stand under this light for a while” covers the basics, red light therapy is (fortunately) more complex. Patients typically undergo multiple treatments during which they’re exposed to low-level lights. The light waves are said to stimulate production of collagen, an important protein found throughout the body. The Los Angeles Times also reports that under the right conditions red light therapy can reduce inflammation, potentially allowing tissues to heal more quickly than they would in the absence of treatment. So, why is red light more therapeutic than other types of light? It isn’t—at least, not as a rule. Some light therapies also use blue lights or full-spectrum lights, but different wavelengths of light have different effects. For example, blue light is more effective than red light for managing the symptoms of seasonal affective disorder (SAD), while red light seems more effective for certain cosmetic skin treatments. The main difference is the light’s wavelength and intensity. Red light has a longer wavelength than blue light, which allows it to penetrate deeper into tissues. Its waves also have a lower frequency, which may make them better suited to promoting pain reduction. No matter what type of light you’re being treated with, the exact wavelength is important; you can’t simply sit under a red traffic light for half an hour and expect any results (other than maybe a traffic ticket).

How do dermatologists use red light therapy?

In dermatology, red light therapy is more accurately called low-level laser light therapy (LLLT). Proponents of the technology claim that LLLT can successfully treat various conditions including acne, vitiligo, and psoriasis. For conditions like acne, red light therapy seems to be effective, but it’s often less effective than topical treatments and medications. “[Light therapy is] definitely nowhere near first line,” says Klein, who offers light therapy services at her clinic in Connecticut, “but it’s good for [acne] patients who don’t want to take prescription medications.” For example, one of Klein’s patients decided to use light therapy for acne treatment prior to a wedding since other options could have caused unwelcome side effects (nobody wants an upset stomach on their big day). Klein says that phototherapy can be effective for treating acne, although it’s not necessarily the cheapest or most effective option. “Generally, unless they’re coming every week or two, [light therapy] is not going to make a great difference, and it’s not usually covered by insurance,” Klein says. “We offer treatments for $75, and honestly, we do that for the patients … It’s not something we make money on.”

Can red light therapy tone the skin or reduce wrinkles?

Proponents of red light therapy often claim that it can rejuvenate the skin, reducing the appearance stretch marks and wrinkles. “It’s thought to potentially incite collagen [production],” Klein says. “I don’t know that we really have any studies backing that up. It may potentially give you a glow.” We looked into the available research, and it’s a mixed bag. A 2014 study found that red light therapy wasn’t any more effective at treating wrinkles than broadband photobiomodulation, which uses a broader range of light wavelengths. However, that study found that both light sources “demonstrated efficacy and safety for skin rejuvenation and intradermal collagen increase when compared with controls.” Several other studies seem to indicate that light therapies could improve the appearance of skin, but the American Academy of Dermatology notes that while light treatments can be effective for that purpose, patients should only pursue those therapies with help from a physician. That’s also true if you’re looking to regrow lost hair. Some studies do show that low-level laser therapy can promote hair growth in humans, but the wavelength and intensity of the light source are important factors, so seeking out treatment from a qualified professional is essential.

Can red light therapy be used to manage chronic pain?

Here’s where we get into slightly murky waters. There’s substantial evidence to suggest that LLLT can help relieve pain better than a placebo. The problem? Scientists aren’t totally sure how the therapy prevents or lessens pain. One theory is that it inhibits neural enzyme production, and there’s some evidence to suggest that LLLT can increase endorphin production while enhancing blood flow. That said, red light therapy might simply reduce inflammation by providing a modest heat source, in which case an electric blanket would serve the same function. Researchers also disagree about the extent of red light therapy’s effect. A 2010 study found that phototherapy patients experienced no difference in chronic pain as compared to placebo groups, while another meta-analysis from the same year found that phototherapy was remarkably effective for pain management.   Some scientists believe that the issue is in the methodology, meaning physicians likely aren’t using the same techniques when treating chronic pain patients. Likewise, pain is extraordinarily difficult to study since research relies on self-reporting from patients. “Studies differ in overall dosage and wavelength which limits the ability to accurately draw conclusions,” wrote J. Derek Kingsley, et al, in a 2014 research review. “Pain is a very complex condition that manifests itself in a variety of different forms. Perhaps there is no set standard of care that will encompass everyone’s needs. However, it is clear that LLLT may be beneficial for many individuals suffering from pain, regardless of the condition that is causing it.”

Can red light therapy kill cancer cells?

Dermatologists can use photodynamic light therapy to destroy cancer cells. As fantastic as that might sound, there are, of course, caveats, and you’re certainly not getting this benefit from a tanning bed outfitted with a few red light bulbs. Typically, doctors treat patients’ precancerous growths with a topical aminolevulinic acid, then use a red or blue light to activate the medication. This isn’t what most people think of as “red light therapy,” though, since the medication is doing all of the heavy lifting. It’s also why over-the-counter phototherapy treatments are ineffective for treating things like cancer. While there’s some evidence that targeted light therapies could effectively treat tumors in humans, the technology isn’t there yet. “Half of what [dermatologists] do all day is dispute marketing claims,” Klein says. “Medical professionals can’t make claims without data, but med-spas and other professionals can. So I’d just tell people to be careful and to research claims for themselves.” The takeaway: If you you have a skin growth that’s concerning you, give your dermatologist a call instead of trying to treat it yourself.

Can red light therapy cause cancer?

Melanomas are the deadliest form of skin cancer, and sadly, even one indoor tanning session can increase a person’s risk of developing a melanoma by 20 percent. Since some tanning salons now offer services that use red light, we wondered: Could a red light therapy lamp cause cancer? In a word: Nope. Tanning lamps create ultraviolet light, which has a shorter wavelength than any form of visible light. Ultraviolet light is a form of ionizing radiation, which is capable of disrupting DNA and causing cancer. Red light, on the other hand, is non-ionizing radiation. Its wavelength is too broad to cause a carcinogenic effect, and while some researchers have expressed concerns that low-level light therapy could cause existing cancers to spread, those concerns appear unfounded. Red light therapy doesn’t have too many side effects outside of potential eye strain, so if you enjoy sitting under the red lights at your local gym or tanning salon, go for it. Of course, that assumes that the red light device is being used properly. Which reminds us…

What should you know about getting red light therapy?

Outside of a doctor’s office, the most common uses of red light therapy are workout recovery and cosmetic enhancement. Many of the businesses that offer red light therapy won’t make the specific claims referenced in this article because they don’t want to draw the ire of the Food & Drug Administration (FDA), which issued a letter in 2011 warning consumers about inaccurate red light therapy claims.   At the time, tanning salon owners were simply replacing the lamps in their tanning beds and booths with red lights, then claiming to offer the full therapeutic benefits of red light therapy and LLLT to customers. That was an issue because the wavelength and frequency of a phototherapy light matters, meaning you can’t just hang a red light bulb and call it a day. That said, it’s certainly possible that some over-the-counter products and services could be effective for some issues that red light therapy has been claimed to fix. The problem is that there’s no way to know for sure. While the FDA approves some types of lamps for certain therapeutic purposes,  it’s important to know most of the products on the market are not FDA approved. If you’re considering red light therapy product, you can search through the FDA’s database of cleared medical devices. Otherwise, take any pseudoscientific product claims with a big grain of salt. Red light therapy isn’t magical, and while it’s a promising field of scientific study, it also gives less-than-reputable marketers a new way to make loads of money. If you’re interested in trying red light therapy, carefully consider the potential benefits of a device or treatment, then make sure that those claims have strong scientific support. If you end up trying out a red light therapy sauna, that’s fine (and please take an ’80s-inspired selfie). Just make sure that the light source is actually red light, since ultraviolet light can be very dangerous.  Ultimately, red light therapy and other forms of phototherapy might be enormously beneficial, but as with all health products, the best piece of advice is simple: If it sounds too good to be true, it probably is.

What Science Says About Red Light Therapy

HealthyWay Staff Writer
HealthyWay’s Staff Writers work to provide well-researched, thought-provoking content.