A new study from the University of Arizona is testing whether or not green light can help certain patients with pain.

UA Assistant Professor Mohab Ibrahim said certain characteristics of trees can help pain, so he tested it.

“Maybe there is something out there that is making my headache better,” Ibrahim said of his pain and of the pain his brother suffered. His brother found relief while sitting outside among trees.

So, Ibrahim decided to experiment with a characteristic of trees to see if he, his brother and other pain sufferers could find relief on an ongoing basis: the color green.

Ibrahim and a team tested varying intensities of green colored light on rats and found that symptoms were reduced after exposure.

“We actually have explored other colors. Actually blue also produced anti-pain effect, but it wasn’t as potent or as effective as green,” he said.

He said the color of the light was varied by intensity and length of exposure. The therapy is now in human trials. Preliminary results show a 40 to 50 percent reduction in pain.