We've all been told to wear sunscreen when spending time outdoors, but new research indicates blocking too much of the sun may be bad for your health.

Researchers say people living in northern countries -- particularly Scandinavia -- have less access to the sun and therefore less vitamin d production.

In a new study, experts found people living in countries near the equator were less likely to die from major cancers than those in northern countries -- and they think vitamin d may have something to do with it.

They suggest people who don't spend time outdoors increase their vitamin d intake through diet and supplements.

They also say creating sunscreens that allow u-v-b rays to penetrate the skin may help.

In other medical news…

Experts warn too much time in the sun can be dangerous.

Skin cancer of all types is the most common cancer in the US, yet a new report finds most American adults engage in behaviors that increase their risk for the disease.

Whether it's at the beach or on the slopes, many Americans do not wear sunscreen or protective clothing, and they do not spend time in the shade.

The risk was particularly increased among young adults.