 Background: Ageing is associated with an increased risk of cognitive decline and depression. Vitamin D plays an important role in many of the symptoms and conditions related to advanced age, including impaired balance, falls and osteoporosis. Vitamin D also has a physiological effect on the function of the central nervous system, and studies have suggested a relationship between this vitamin and changes in affect and cognitive function in the elderly. The investigators propose a pilot study to examine the relationship between below-normal levels of Vitamin D to affective symptoms and specific cognitive functions in the elderly. 