Maybe it’s not the vitamin D from the sun that helps people with multiple sclerosis, but rather the UVB radiation.
That’s right… the same radiation that causes skin cancer.
A study out of Harvard under the team of Helen Tremlett, PhD, a professor in neuroepidemiology and multiple sclerosis at the Djavad Mowafaghian Centre for Brain Health, mapped the sun exposure over the life of multiple sclerosis patients using state-of-the-art information from NASA.
Taken from the Nurses’ Health Study cohort, 3,226 people with multiple sclerosis (MS) were geocoded.
This information was then cross referenced and analyzed with data from NASA tracking UVB radiation.
“It is a huge and powerful resource to look at these kinds of questions. They have been following women who were nurses across the U.S. Over time, some have developed conditions such as MS,” Tremlett told Healthline.
Those who lived in high UVB areas had a 45 percent lower risk of MS. Also associated with a reduced risk was high summer sun exposure in high UVB areas.
“People didn’t have to have a lot of skin showing, but just to be outside in the sunlight,” Tremlett said.
The body creates vitamin D when exposed to sunlight. However, the study suggests that there is more than vitamin D at play here.
“We don’t know how it works,” said Tremlett, “It could be, for example, that the sun hits the retina in the back of the eye, which influences how much melatonin you produce, which affects circadian rhythm. This could affect wake and sleep cycle and immune regulation,” Tremlett suggested.