Vitamin D HIV Study on Postmenopausal Women

The purpose of this study is to determine the effects of vitamin D on measures of bone health and immune function in HIV infected postmenopausal women. The investigators prior research with this population revealed that low vitamin D levels are very common. Prior research with this population also revealed that Vitamin D is necessary for the body to absorb calcium and is important for the health of the bones. When vitamin D levels are low, there are increased risks of bone loss, muscle weakness, falls and fractures. Low levels of vitamin D have also been associated with impaired immune function. This study will help us learn whether two different doses of vitamin D will improve bone health and immune function.