Vitamin D is important for good health, growth and strong bones. Vitamin D is mostly made in the skin by exposure to sunlight. Most foods contain very little vitamin D naturally, though some are fortified with added vitamin D. Hypovitaminosis D is associated with cardiovascular disease, the metabolic syndrome, type 2 diabetes mellitus, cancer as well as with increased mortality. Further, Vitamin D deficiency is related to depression and impaired cognitive function. Increasing age and elevated body fat mass contribute to an increased risk of Vitamin D deficiency. A mild lack of vitamin D may not cause symptoms but can cause tiredness and general aches and pains. A more severe lack can cause s rious problems such as rickets (in children) and osteomalacia in adults). During menopause, the decline of estrogens results in increased bone turnover, a decrease in bone mineral density and elevated fracture risk. Treatment is with vitamin D supplements. Some people are more at risk of vitamin D deficiency, and so are recommended to take vitamin D supplements routinely. These include all pregnant and breastfeeding women, all infants (babies) and young children aged 6 months to 5 years, people aged 65 and over, and people who are not exposed to much sun. There are precise recommendations regarding a sufficient Vitamin D intake in order to prevent bone loss in peri- and postmenopausal women. It is also recommend routine supplements for certain people with darker skin, and for people with certain gut, liver or kidney diseases.