Everything You Need to Know About the Benefits of Light Therapy

Cosmopolitan

20-05-2025

Unless you've sworn off social media, you've probably noticed that LED face masks are everywhere recently. Like, I can't go a single day without swiping past at least one Instagram Story of an influencer wearing one. And if you're anything like me (read: always curious about the latest wellness trend), you might be wondering whether light therapy has any actual benefits.
To answer that question, we need to zoom out a little bit. Light therapy—aka phototherapy—isn't just something that exists in the beauty world. It's actually a pretty complicated topic. Light therapy comes in many different forms, and it can be used to treat a whole bunch of different health concerns. In fact, it's been proven to help with everything from mental health to chronic pain and sleep disorders.
Because I have zero medical degrees, I asked five experts who do to explain how light therapy works, what conditions it can help with, and which devices are the best if you're curious about trying it at home. Read on for the scoop.
Since light therapy is used in so many different contexts, it's tough to narrow down just one definition of what it is and how it works. But to keep it really basic, light therapy involves being exposed to specific wavelengths of light to treat a range of mental and physical conditions. It generally uses LED (or light-emitting diode) light, but the exact color of the light, the intensity, and the length of exposure will depend on what you're trying to treat.
Light therapy works in two main ways: It's either applied onto the skin or exposed to the eyes (again, depending on what condition you're dealing with), to change a biological function in the body, explains Mohab Ibrahim, MD, PhD, a professor of anesthesiology at The University of Arizona and medical director of the University's Comprehensive Center for Pain and Addiction. We'll get into more specifics later on what functions and conditions it can help with.
Light therapy can have a lot of benefits. Here, I've outlined five of the most common ways it's used and who might be a good candidate to try it.
If your mood tends to take a nosedive in the fall and winter, you've probably heard of SAD lamps. These are light therapy lamps that simulate natural sunlight, helping your body to decrease production of melatonin (the hormone which regulates your body's sleep-wake cycle) and increase production of serotonin (a hormone which helps regulate mood), explains Amanda White, LPC, LMHC, therapist and founder of Therapy for Women Center.
They're usually called SAD lamps because they're most commonly used to treat seasonal affective disorder (SAD), but light therapy lamps can actually help with all types of depressive disorders, says psychiatrist Seth A. Eappen, MD. A 2024 study published in JAMA Psychiatry found that bright light therapy (another term for light therapy) led to a 41 percent remission rate in people with nonseasonal depression—higher than the remission rate for other treatment methods, like antidepressants, alone. Another benefit is how quickly it can work. Some patients notice improved mood within days, while antidepressants can take weeks to kick in, White adds.
To feel the benefits, Dr. Eappen recommends getting a lamp that emits 10,000 lux and starting with 15-minute sessions every day. You can use the lamp anytime before 2:30 p.m., he says—after that point, it might start to mess with your sleep. Sit with the lamp about 12 inches away from you and avoid looking directly at it. As long as you don't notice any negative effects like headaches, sleep disturbances, or overstimulation, you can keep increasing the length of your sessions by 15 minutes each week until you hit 60 minutes a day, he says.
Good news: It turns out those trendy LED face masks aren't pure snake oil. LED exposure has proven anti-aging benefits.
'Cells in our body respond to [LED light], and the energy they receive [from it] is used to 'refuel' them, giving them new energy to replace old damaged cells with new youthful ones,' explains dermatologist Rachel Nazarian, MD. Benefits include increased collagen production, improved skin elasticity, and reduced pigment unevenness. In other words, with regular use, you can be left with fewer wrinkles, a more even complexion, and plumper skin.
It's important to remember that these benefits come from red LED light specifically, Dr. Nazarian adds. Both at-home and in-office treatments can be effective, but you'll have to be more patient and consistent with an at-home device in order to see results. When shopping for an LED face mask, look for a model that has FDA clearance, meaning it's been shown to be safe and effective. Therabody and Omnilux both make masks that have been FDA-cleared.
Some preliminary research suggests that blue LED light might help clear acne—but it's still early. A 2024 study published in the Journal of Cutaneous Medicine and Surgery found that people with mild to moderate acne saw some improvement in their skin after getting three or more treatments for four weeks straight. But Dr. Nazarian says more research needs to be done before she'd feel comfortable recommending blue light therapy for acne. It's not well understood yet, and there are potential skin damage risks that need to be studied further, she says.
Beyond anti-aging, light therapy has been proven to help with skin conditions like eczema and psoriasis. According to the National Eczema Association, phototherapy can help with itching and inflammation. You'll need to have it prescribed and administered by a derm, though. Similarly, the National Psoriasis Foundation says that phototherapy has been shown to slow the growth of affected cells, in turn reducing symptoms.
Light therapy can also be helpful for certain types of chronic pain. The most well-understood form is red light therapy, which is most commonly used to treat joint pain and arthritis symptoms. Let's say you messed up your knee in a workout class, and now it hurts whenever you walk long distances. Using a red light device directly on your knee can help decrease inflammation, in turn reducing the amount of pain you feel, says Dr. Ibrahim.
According to a 2021 study published in The Journal of Pain, applying red light through the skin—even for just a short period of time—can decrease joint pain, nerve pain, inflammatory pain (think: sprains and strains), and even postsurgical pain. If you want to try it at home, Dr. Ibrahim recommends opting for a device that's been FDA cleared, like the Kineon MOVE+ Pro. Just keep in mind that when it comes to pain relief, there's no one-size-fits-all solution. Similar to how you might respond better to Advil sometimes and Tylenol other times, depending on the specific type of pain you're dealing with, red light therapy isn't a cure-all for physical pain, he adds.
There's also emerging evidence that suggests green light therapy can reduce pain. Unlike red light therapy, which is applied through the skin, green light therapy is applied through the eyes. Based on the research that's been done so far, experts think that green light alters the pain centers in the brain, turning off mechanisms that amplify pain and turning on mechanisms that suppress pain, explains Dr. Ibrahim. So far, studies indicate that it can be helpful for people with conditions like chronic migraines and fibromyalgia.
Since red light therapy can reduce inflammation, it also has potential workout recovery benefits. Muscle soreness often comes with an inflammatory response as the body works to repair the muscles you've just broken down in the gym. It varies from person to person, but applying red light to the area where you're sore might make you feel less achy and help you recover faster, says Dr. Ibrahim.
Research is limited, but a 2016 study published in the Journal of Biophotonics found that using red light therapy and near-infrared light therapy (a slightly different wavelength than red) either before or after a workout can increase overall performance and reduce fatigue and inflammation.
Last but certainly not least, light therapy has proven sleep benefits. That's because light exposure affects the body's circadian rhythm, aka our body's natural sleep-wake cycle. Ideally, your circadian rhythm is synced up to the 24-hour cycle, helping you to wake up when the sun comes up and prepare for sleep when the sun goes down. But sometimes it gets out of whack, making it hard to wake up in the morning or fall asleep at a normal time. Light therapy can help reset your body's 'clock,' says Brandon Peters, MD, a neurologist and sleep medicine specialist.
'Appropriately timed exposure to light will help everyone sleep better,' he explains. He recommends trying to get 15 to 30 minutes of direct sunlight exposure within 15 minutes of waking up. If you're going outside, don't wear a hat or sunglasses, since that can lessen the impact. Exposing yourself to light first thing in the AM will make it easier for you to feel awake and refreshed, and also help you feel a natural desire to go to sleep at night, he says. It can also be beneficial for sleep disorders like insomnia, and situational issues like jet lag.
Another option is a light therapy box. Dr. Peters recommends getting one that has an intensity of at least 10,000 lux of either white or blue light. Sitting in front of it for 15 to 30 minutes in the morning will provide a lot of the same benefits that natural sunlight exposure does.
Here, the answer depends on which benefits you're looking for. If you're after mental health, sleep, or skin benefits, you'll want to do light therapy pretty regularly. For mental health and sleep, make light therapy part of your daily routine, following the time guidelines the experts mentioned above. But when it comes to your skin, you can be a little more lax. Most LED face mask brands recommend that you use them three to five times per week to see results. In terms of how often you should do light therapy treatments for specific skin conditions like eczema, you'll need to talk to your doctor.
If you're interested in light therapy for pain relief or muscle recovery, you can use it on more of an as-needed basis. There's no need to strap on your red light therapy device every day—unless you're experiencing pain on the daily. And if that's the case, it's important to reach out to your doctor to figure out the root of your issue.
Kara Cuzzone is a New York City-based writer, editor, and artist. She has over seven years of experience covering health, wellness, and shopping-related topics for sites including Forbes, Cosmopolitan, Byrdie, Wondermind, and PureWow.