Like most vitamins, vitamin D may be obtained in the recommended amount with a well-balanced diet, including some enriched or fortified foods. In addition, the body manufactures vitamin D when exposed to sunshine, and it is recommended people get 10 to 15 minutes of sunshine 3 times a week. Update Date: 08/04/2008Elizabeth H. Holt, MD, PhD, Assistant Professor of Medicine, Section of Endocrinology and Metabolism, Yale University. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.