Defining Optimal Doses of Vitamin D for Chemoprevention in Blacks.
- 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
- 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.
Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Single Group Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Prevention
Among Blacks, identify a dose of oral vitamin D supplementation that will result in levels of plasma 25(OH)D that would be predicted to reduce colorectal cancer incidence.
Baseline, 3months, 6months
Edward Giovannucci, MD, ScD
Harvard School of Public Health/Brigham and Women's Hospital
United States: Institutional Review Board
|Dana-Farber Cancer Institute||Boston, Massachusetts 02115|