Story at a glance

  • Green light is often associated with positive emotions and has even been found to relieve pain in some studies.
  • A new study is testing daily green light therapy on patients with migraines.
  • Preliminary results of the study show that green light can lessen the intensity of pain in migraines and how often they occur.

Millennials are credited with “killing” a lot of traditions and practices, but they’re embracing houseplants and gardening with verve. The houseplant industry is thriving, and while there are many reasons why, there’s one that’s plain to see — they’re green. 

New research is exploring whether the color green and especially green light could help relieve pain. It's backed by research into light sensitivity with migraines, finding that green light is associated with positive emotions and is less likely than others to worsen pain

Dr. Mohab Ibrahim, an associate professor at the University of Arizona, is leading a study testing if daily exposure to green light can relieve migraines and other kinds of chronic pain. He told NPR he was inspired to look into the connection when his brother said that when he had a headache he wouldn’t take medicine but would sit in a garden, and eventually the pain would die down. 

Ibrahim told NPR that on average, people exposed to green light daily experienced a 60 percent decrease in the intensity of their migraines and a drop from 20 migraines a month to about six. For some of the about 25 patients in the study, that change happened within days, and for others, it happened over several weeks. 

The results of the study aren’t published yet, but seem to mirror a study Ibrahim led testing the long-lasting effects of green light on both acute and chronic pain in rats. The study found that when rats were exposed to light, those seeing green light were less sensitive or reactive to pain. 

"We basically made the conclusion that whatever effect is happening is taking place through the visual system," he told NPR. "That's why when we recruited patients, we told them you cannot fall asleep when you're undergoing this therapy."

Ibrahim and his team suspected the green light acted similarly to opioids, he told NPR, and when they tested the opioid reversal drug naloxone on the rats, the pain-relieving effects were reversed. 

With funding from the National Institutes of Health, Ibrahim is also studying the effect of green light for conditions such as fibromyalgia, nerve pain related to HIV and chemotherapy and a painful bladder condition called interstitial cystitis.

"In my opinion, the most ideal drug or therapy is something that's first safe, effective and affordable," he said to NPR.

Published on Dec 17, 2019