 Obesity is an increasing health problem with numerous metabolic complications. Vitamin D deficiency is common in obesity, and in epidemiological studies vitamin D deficiency has been linked to metabolic complications, such as type 2 diabetes, insulin resistance and cardiovascular disease, as well as myopathy, osteoporosis and depression. In obesity, a low grade inflammation is present in the fat tissue, thereby releasing inflammatory molecules to the blood stream. In cell line studies as well as small clinical studies vitamin D has been shown to have the ability to reduce inflammation and cell growth. 