Vitamin D for Chemoprevention

Defining Optimal Doses of Vitamin D for Chemoprevention in Blacks.

This study will help us know the effects of Vitamin D pills in Blacks. The results of this study may be the first step in creating ways to prevent the risks of colon and prostate cancer. It will also help us develop ways to reduce colon cancer and prostate cancer among Blacks. This study will find out if Vitamin D pills can increase Vitamin D to healthy levels in our bodies.

• Participants will be asked to answer some questions about their diet, exercise and health. In addition, participants blood pressure will be taken. These assessments will occur at baseline, 3- and 6-month appointments. At baseline only, we will measure skin tone with a tool called the Photovolt 577.
• A small blood sample will be taken to see how much Vitamin D is the body and will also look at levels of other markers of disease such as proteins, hormones, and genes.
• Participants will take a vitamin pill every day for three months and be randomly assigned to one of four different types of pills.
• Participants will be called or visited at least every two weeks. They will be asked questions to determine if they have any side effects associated with high levels of Vitamin D.
• At the beginning of the second and third months, participants will be provided with more pills. At the end of the third month, another blood sample will be taken. Three months after that, the final blood sample will be taken.

Inclusion Criteria:

• Between the ages of 30 and 80 years
• Comfortable communicating in English
• Currently has a primary care physician
• Willing to discontinue vitamin D or calcium supplements
• Willing to have all protocol specific tests run

Exclusion Criteria:

• Plans on taking a vacation or travel to a sunny region within 3 months of vitamin supplementation period except for a short period (i.e. 1 weekend)
• Pregnant or breast feeding or planning on becoming pregnant in the following year
• Pre-existing calcium (including hypercalcemia), parathyroid conditions (including hyperparathyroidism), sarcoidosis
• No concurrent active malignancies (other than non-melanoma skin cancer) or previous diagnosis of prostate cancer
• Cognitively impaired
• Active thyroid disease (e.g. Graves, Hashimoto's or thyroiditis)
• History of nephrolithiasis, chronic liver disease, chronic renal disease, or renal dialysis