Sunlight the “New” Best Cold Remedy?

It may well be that the lack of sunshine in the wintertime is the biggest reason we get more colds and flues during that time. It turns out, that sunshine directly charges the immune system – and it has nothing to do with vitamin D!

Sunshine must be the most underutilized and free remedy available to mankind. A recent notable study found that sunshine is the biggest climate element affecting mental health. Workplace sunshine helps increase sleep quality, physical activity and overall quality of life – whereas artificial light is harmful. Sunlight is even shown to help us lose weight.

In 2014, researchers declared that sunshine could reduce the risk of death from all causes. In fact, they said,

We suspect that the benefits to heart health of sunlight will outweigh the risk of skin cancer.

And now we may have the missing puzzle piece why…

Sunlight offers surprise benefit — it energizes infection fighting T cells

Georgetown University Medical Center researchers have found that sunlight, through a mechanism separate than vitamin D production, energizes T cells that play a central role in human immunity.

Their findings, published today in Scientific Reports, suggest how our skin – the body’s largest organ – stays alert to the many microbes there.

The study’s senior investigator, Gerard Ahern, PhD, associate professor in the Georgetown’s Department of Pharmacology and Physiology, said:

We all know sunlight provides vitamin D, which is suggested to have an impact on immunity, among other things. But what we found is a completely separate role of sunlight on immunity. Some of the roles attributed to vitamin D on immunity may be due to this new mechanism.

They specifically found that low levels of blue light, found in sun rays, makes T cells move faster — marking the first reported human cell responding to sunlight by speeding its pace.

Ahern says,

T cells, whether they are helper or killer, need to move to do their work, which is to get to the site of an infection and orchestrate a response.

This study shows that sunlight directly activates key immune cells by increasing their movement.

Ahern notes that while production of vitamin D required UV light, which can promote skin cancer and melanoma, blue light from the sun, as well as from special lamps, is safer.

     Explore: How Sunshine helps with Depression and Anxiety

And while the human and T cells they studied in the laboratory were not specifically skin T cells — they were isolated from mouse cell culture and from human blood — the skin has a large share of T cells in humans, he says – about twice the number circulating in our blood.

“We know that blue light can reach the dermis, the second layer of the skin, and that those T cells can move throughout the body,” he said.

The researchers further decoded how blue light makes T cells move more by tracing the molecular pathway activated by the light, Georgetown reported.

What drove the motility response in T cells was synthesis of hydrogen peroxide, which then activated a signaling pathway that increases T cell movement.

Hydrogen peroxide, they reported, is a compound that white blood cells release when they sense an infection in order to kill bacteria and to “call” T cells and other immune cells to mount an immune response.

Amazing, eh!

Ahern concluded [emphasis added]:

We found that sunlight makes hydrogen peroxide in T cells, which makes the cells move. And we know that an immune response also uses hydrogen peroxide to make T cells move to the damage.

This all fits together.

Ahern is eager to continue these findings and figures it might make sense to offer patients blue light therapy to boost their immunity.

What do you think? Have these discoveries made you want to catch some wintry sun?