With apologies for a bad pun, this is vitamin D's moment in the sun. The recent medical literature is replete with reports on the consequences of vitamin D deficiency and its beneficial effects in preventing or treating a variety of maladies. Although the focus of most research has been on bone disease, in adults vitamin D deficiency has been linked to conditions as diverse as asthma, cancer, cardiovascular disease, diabetes mellitus, depression, and schizophrenia.1 Overall, it has been estimated that as many as 1 billion people have hypovitaminosis D.1