Lack of sun could be to blame for winter weight gain, Alberta study suggests

People who are having difficulties shedding some pounds in New Year’s resolution season may have the lack of sun to blame for their struggle, new University of Alberta research has found.

It's still early, but U of A researchers found fat cells shrink when exposed to blue light from sun

The sun could be the key to shedding those pounds, a new U of A study suggests. (Rick Bremness/CBC)

Are you struggling to maintain that New Year's resolution to lose weight? A new University of Alberta study says the sun may be to blame for your extra winter pounds.

The research, led by pharmacology professor Peter Light, shows the fat cells just beneath our skin shrink when exposed to sun rays — meaning the cells release some of the fat and hold less of it.

"The blue wavelengths of light … actually penetrate the skin and can activate the fat cells so that they lose some of the fat," Light told CBC's Radio Active Wednesday.

Like many of science's greatest discoveries, this potential breakthrough was discovered by accident — Light and his team were trying to engineer the fat cells to make insulin to help treat Type 1 diabetes.

In their process, they found the cells were responsive to light. Light said he's finally living up to his last name.

Other studies have shown the blue wavelengths of light have other effects on our bodies. The light is emitted from cellphones, laptops and other LED monitors and has been shown to suppress melatonin and increase alertness.

Light said the pathways stimulated in the eyes from staring at screens are the same pathways they're seeing in the fat cells.

He said his new findings could help make sense of the winter weight gain many people experience in a northern climate like Edmonton.

Still early

With some sun exposure confirmed to help generate vitamin D in the body, Light said this discovery be another benefit. "It may help regulate your body weight and a lack of it may actually lead to extra storage of [fat] in the winter."

But he said his findings suggest that current technology — like tanning beds or blue light lamps, for example — haven't shown the same effects as sunlight.

"We think that that great big nuclear reactor in the sky, the sun, is what's required," Light said. "We need really intense light to actually penetrate the skin."

Only one to five per cent of blue light penetrates the skin, Light said, and the sun is able to do that with limited exposure.

But before you start spending exorbitant amounts of time in the sun and calling it a weight-loss routine, Light said it's still early and the study published is just a new avenue for them to explore.

"The study we just published, actually, was more of an observation of the effect," Light said. "Now, we need to know what the underlying mechanism is."

Listen to Radio Active with host Portia Clark, weekday afternoons on CBC Radio One, 93.9 FM/740 AM in Edmonton. Follow the show on Twitter: @CBCRadioActive.