Getting a lot less sunlight in the winter doesn't just affect our moods. It may also increase the risk of dying from cancer. Researchers say the key is Vitamin D, produced in our skin by ultraviolet rays of the sun.
"Assuming you go out in the sun, Vitamin D increases as you get closer to the equator," explains Dr. Richard Setlow with the Brookhaven National Laboratory.
Brookhaven National Laboratory's Richard Setlow and colleagues in Norway compared cancer rates and cancer death rates at different latitudes. People at high latitudes, like in Scandinavia, get less direct sunlight as opposed to people in Australia, who live closer to the equator.
The researchers found while skin cancer rates are higher closer to the equator, death rates from all types of cancer are actually lower.
"The importance of Vitamin D is it tends to protect against the lethal effects -- death from the cancer," says Dr. Setlow.
The research published in The Proceedings of the National Academy of Sciences shows the benefit of moderate sun exposure seems to outweigh the risk of skin cancer. However, Dr. Setlow reminds us we can also get Vitamin D from foods or supplements.
"You're getting a benefit that tends to decrease the death rate from cancers -- cancers in general, not just skin cancers," says Dr. Setlow.
It's more evidence that a little sunshine can boost more than your spirits.
Since sunscreens block the UV-B rays that produce Vitamin D, researchers say moderate sun exposure means 10 to 15 minutes in the sun without sunscreen.