This is yet another example of why sun exposure is an important part of a healthy lifestyle. Because of changes in the way we live, people today are not spending time in the sun, and thus aren't getting nearly the amount of vitamin D that humans have for thousands of years. This is also intensified by the exaggerated fear of the sun that exists today. This sun avoidance is leading to an epidemic of low vitamin D levels which leads to increased risk of more than 100 different conditions (http://www.ncbi.nlm.nih.gov/pubmed/22502819). It's about time that we embraced the tremendous value of healthy sun exposure.