Last week, we talked about how the rules on sun exposure and sunscreen might be changing. When we spend a short time in the sun each day, our bodies manufacture vitamin D, a necessary nutrient and something that's hard to get as efficiently elsewhere. A recent study has now found that having appropriatly high levels of vitamin D circulating in your body can significantly reduce the risk of breast and colon cancer.

If you're taking a daily vitamin, you're probably getting about 400 IU of vitamin D each day, in addition to the amount you get through milk or fish. Some experts believe that's not enough, and are suggesting people add vitamin D supplements to their diets. Part of the reason many of us are deficient in the vitamin is that it's only available in a few foods -- mostly milk and oily fish like mackeral -- and because of we don't get enough sunshine.

What's an appropriate amount of time in the sun? Experts say 15 minutes for fair-skinned people and 25-minutes for those with darker skin, and that you should have about 50% of your skin exposed. Also, delay taking a shower right away or dipping into the pool; your vitamin D levels will get a boost from allowing sweat and oil to sit on your skin a little longer.
Experts now say we can tolerate between 1,000 and 2,000 IUs of vitamin D per day and highly recommend increasing the amount we take each day. Vitamin D is fat soluble, however, so there is a risk that you can take too much. Personally, I recommend talking to your doctor before increasing the amount of anything you take above the recommended dose, but this research is certainly compelling. And while you can't overdose on the vitamin D you get from the sun, you can get a sunburn and increase your risk for skin cancer. So keep your sunscreen-free time limited to a to the amount of time that's right for your skin tone, then cover up with your SPF flavor of choice.