We used to hear that we got enough vitamin D just from casual sun exposure on our face and hands, since our bodies produce vitamin D. We know now that isn’t necessarily true. While our bodies make 10,000-20,000 IU of vitamin D after 15-20 minutes of unprotected sun exposure over most of our bodies (think swimsuit on the beach in July), if we live in northern latitudes (anywhere north of Atlanta, research shows), the sun’s rays can’t do their job for most of the year. Basically, you can make snow angels outside, naked, all afternoon and not make any vitamin D if you live in New York and it’s February. Those with darker skin colors will take up to 5 times as long to make the same amount of vitamin D under ideal conditions. Remember, this is unprotected sun exposure … sunscreen blocks the vitamin D-making rays.