Vitamin D is being produced in the skin from sun exposure, and helps to create strong bones. The amount of sun exposure one receives varies greatly from person to person, and people are advised against sun exposure to reduce the risk of skin cancer. People who are older and living in institutions or who have dark skin pigmentation may be at increased risk for getting too little vitamin D. Very few foods in nature contain Vitamin D, for example fatty fish such as salmon or tuna. Vitamin D is therefore added to common foods in the United States including milk, cereal, yogurt and orange juice. When levels of vitamin D are low, patients may experience bone pain and muscle weakness, or no symptoms at all. Regardless of the symptoms, Vitamin D deficiency may be associated with other chronic conditions such as asthma, diabetes, hypertension and cancer. Vitamin D levels can be restored through dietary changes, supplements and/or spending more time in the sun.