Tip: The Easiest Way to Get Healthier

Vitamin D deficiency is a big problem. It's extremely common, and it can cause or exacerbate diseases like multiple sclerosis, cancer, and heart disease. Furthermore, Vitamin D plays a big part in the health of the immune system. Low Vitamin D can also play a role in depression. On the flip side, boosting your Vitamin D levels if they're low has been shown to increase athletic performance.

Unfortunately, only a few foods (like salmon, cod liver oil, mushrooms, and, to a lesser degree, egg yolks) contain substantial amounts of Vitamin D.

As such, most Americans get it from taking Vitamin D supplements or Vitamin D fortified dairy products. Your body can manufacture its own, provided it gets enough sun exposure, but as you know the dermatologists have made that practice rank right up there, health-wise, with chain-smoking unfiltered cigarettes while wearing a bag over your head.

The problem, according to leading expert Michael F. Holick, PhD, MD, is that supplemental Vitamin D isn't the same as the Vitamin D produced by exposing your body to sunshine. The Vitamin D produced by sun exposure enters the bloodstream much more slowly and lasts at least twice as long as supplemental Vitamin D.

Yes, chronic sun exposure, i.e., tanning, can lead to various skin cancers, most of which are relatively easy to cure. Sunburns, however, can lead to melanoma, which is linked to 10,000 deaths in the US each year.

People who get short-term, occasional sun exposure (without burning) don't have much to worry about. Besides, there's some debate as to the strength of the link between sunlight and melanoma, as plenty of people get melanoma on parts of the body that aren't typically exposed to the sun, like the butt.

Here are Dr. Holick's recommendations:

• Follow the "no sunburn" rule. He advises people to spend one-half the amount of time in the sun that it would take to develop a mild sunburn.
• Get sun exposure between 10 AM and 3 PM when the sun's rays are the strongest.
• Keep track of the time. People with dark or darker skin can spend about 30 minutes in the sun, while fair-skinned people should restrict it to about 10 minutes.
• Do this three times a week, if possible.
• Don't wear sunscreen (which inhibits Vitamin D formation) during this time, except on your face – very little Vitamin D is produced through exposing the face to the sun, plus it leads to wrinkles. Wear sunscreen the rest of the time.
• Take Vitamin D during times when sun exposure isn't possible.