Is Green Light the Next Great Pain Reliever?

Gulur and colleagues distributed either clear, blue or green-tinted glasses to 45 people ages 46 to 67 with fibromyalgia, a condition in which people experience widespread pain in their muscles. The blue glasses gave some people headaches, but Gulur found, like Ibrahim, that “patients we had given green glasses to didn’t want to give [them] back to us,” she says. While patients said they still felt pain, the green-tinted glasses cut down on their use of opioids and users felt less anxious, the team reported in 2023 in Pain Physician Journal.

Does it work?

Why would seeing green make any difference to how a person experiences pain? Gulur thinks that certain wavelengths might activate our internal painkilling system. Our nervous system has natural ‘on’ and ‘off’ switches for pain. The ‘off’ switch works by releasing endorphins — basically self-made opioids. Absorbing green light might set off a feel-good cascade in our brains and bodies, Ibrahim says.

This is somewhat supported by animal studies. In Ibrahim’s lab, rats exposed to green light after surgery released more endorphins into their nervous systems than animals getting no green light. In that same study, published in 2023 in The Journal of Pain, green light reduced inflammation in the nervous system. Inflammation is linked to all kinds of trouble — not just pain, but also anxiety and depression.

Of course, those same effects could be brought on by a placebo, says Javeria Hashmi, research chair for pain research and associate professor at Dalhousie University in Nova Scotia. Just thinking you’re getting an effective painkiller may be enough to relieve the pain. Alternative therapies for pain are particularly tough to test for placebo. A sugar pill can be used as a stand-in for a drug but not for a wavelength of light.

A practical guide to green light therapy

Word of green light’s promise has created a mini online market for green-tinted products. A quick internet search reveals glasses and lamps promising pain relief.

Yet scientists are still learning whether green light works. Ibrahim’s work suggests that green light therapy is cumulative: The more you do it, the better you feel over time. He suggests people spend at least an hour or more a day exposed to green light to see results. Gulur agrees, suggesting that glasses might prove a better option for people on the move than a lamp.

In the next few years, Ibrahim predicts, hospitals might start handing out green glasses to patients recovering from surgery. Most likely, green light therapy will serve as an add-on to current pain treatments, he says. People who need immediate pain relief will still receive opioids and analgesics. “If someone came in in acute pain — let’s say they broke an ankle — am I going to shine green light on them? Probably not,” he says.

The good news is that green light appears to be risk-free, Gulur says. Buying one of the many green-light products might not solve your problems in the long run and shouldn’t be a replacement for established care. But does that mean you shouldn’t try it? “For people to get engaged with the process of taking care of themselves — that’s what’s most important,” says Hashmi. If that means green light, “for me, it’s a no-brainer,” she says.