This study will evaluate the safety over 6 months of two different doses of vitamin D (cholecalciferol) in men and women age 65 and older. It will also evaluate if supplementation with vitamin D improves physical performance.

120 ambulatory men and women ages 65 to 95 will be enrolled in this study. Each subject will participate in the clinical trial for 6 months.

Parathyroid hormone, vitamin D, and serum and urinary calcium will be measured periodically. Physical performance will be tested at baseline and throughout the study.

Inclusion Criteria:

• ambulatory

Exclusion Criteria:

• hypercalcemia
• hypercalciuria > 4 mg/kg body weight/day
• primary, secondary, or tertiary hyperparathyroidism
• renal insufficiency (serum creatinine > 2 mg/dL )
• history of nephrolithiasis
• treatment with vitamin D (ergocalciferol, cholecalciferol, calcitriol)
• treatment with anticonvulsants
• Paget's disease
• severe cardiac, pulmonary, hepatic, renal, or neurological disease
• life expectancy < 1 year
• participation in another trial

Adverse events were collected during the 6 months of the intervention.