A total of 2,258 (1,130 African Americans and 1128 European Americans) men newly diagnosed with prostate cancer in North Carolina and Louisiana were enrolled into the study between 2004 and 2009. Participants signed informed consent and were interviewed by a trained nurse who collected information on demographics, occupation, family history, health status, health care, prostate cancer diagnosis and screening history, medication use, anthropometrics, lifestyle factors (e.g., physical activity, smoking), and diet and supplement use. Research subjects were asked to recall their diet in the year prior to prostate cancer diagnosis via a modified version of the National Cancer Institute Diet History Questionnaire. Vitamin and supplement use in the year prior to prostate cancer diagnosis was assessed via a validated questionnaire, and current use was assessed by bottle label inventory. Blood, urine, and adipose tissue samples were collected.
