LETTER FROM THE EDITOR Vitamin D deficiency, health and sun exposure: a caveat for the Mediterranean lifestyle

Although the use of vitamin D for its skeletal effects, prevention and therapy against osteoporosis is already widely known, in recent years important data have emerged, proving that vitamin D deficiency correlates an increase in infections risk cardiovascular diseases, auto-immune diseases like multiple sclerosis, type 1 diabetes as well as some malignancies like colorectal and breast cancer. In a recent meta-analysis, published in the American Journal of Clinical Nutrition, the outcomes of 14 pro-spective cohort studies were evaluated in more than 62,000 subjects, revealing a connexion between vitamin D—25 (OH)D levels and mortality. As a matter of fact, the relative risk of mortality lowers with the increase of 25 (OH)D blood levels and the optimal concentration of this sub