Sunshine is much linked to mental health

Sunshine matters a lot, even when it comes to our mental and emotional health.

According to a recent BYU study, the amount of time between sunrise and sunset is the weather variable that matters most for our emotional and mental health.

Your day might be filled with irritatingly hot temperatures, thick air pollution and maybe even pockets of rainclouds, but that won't necessarily get you down. If you're able to soak up enough sun, your level of emotional distress should remain stable. Take away sun time, though, and your distress can spike. This applies to the clinical population at large, not just those diagnosed with Seasonal Affective Disorder.

"That's one of the surprising pieces of our research," said researcher Mark Beecher. "On a rainy day, or a more polluted day, people assume that they'd have more distress. But we didn't see that. We looked at solar irradiance, or the amount of sunlight that actually hits the ground. We tried to take into account cloudy days, rainy days, pollution . . . but they washed out. The one thing that was really significant was the amount of time between sunrise and sunset."

Therapists should be aware that winter months will be a time of high demand for their services. With fewer sun time hours, clients will be particularly vulnerable to emotional distress. Preventative measures should be implemented on a case-by-case basis.

The study started with a casual conversation that piqued Beecher's professional curiosity.

"Mark and I have been friends and neighbors for years, and we often take the bus together," said researcher Lawrence Rees. "And of course you often talk about mundane things, like how are classes going? How has the semester been? How 'bout this weather? So one day it was kind of stormy, and I asked Mark if he sees more clients on these days. He said he's not sure, it's kind of an open question. It's hard to get accurate data."

A lightbulb went off in Rees' head. As a physics professor, Rees had access to weather data in the Provo area. As a psychologist, Beecher had access to emotional health data for clients living in Provo.

"We realized that we had access to a nice set of data that not a lot of people have access to," Beecher said." Rees said, 'Well, I've got weather data,' and I'm like, 'I've got clinical data. Let's combine the pair!' Wonder Twin powers activate, you know?"

The duo then brought in BYU statistics professor Dennis Eggett, who developed the plan for analyzing the data and performed all of the statistical analyses on the project.

The study has been published in Journal of Affective Disorders.