Dietary patterns and risk of prostate cancer in U.S. men.

We prospectively investigated the associations between dietary patterns and risk of prostate cancer in the Health Professionals Follow-up Study. Between 1986 and 2000, 3,002 incident prostate cancer cases were identified in our cohort. Using factor analysis, two major dietary patterns were identified, a prudent and a western dietary pattern. Dietary patterns were not appreciably associated with risk of total prostate cancer. For the highest versus the lowest quintiles, the multivariable relative risk (RR) for the prudent pattern was 0.94 [95% confidence interval (CI), 0.83-1.06], and for the western pattern, the multivariable RR was 1.03 (95% CI, 0.92-1.17). Neither were these associated with risk of advanced prostate cancer [highest versus lowest quintile, prudent pattern (RR, 1.01; 95% CI, 0.68-1.49); western pattern (RR, 1.13; 95% CI, 0.77-1.67)]. Higher western pattern scores were suggestively associated with a greater risk of advanced prostate cancer among older men [highest versus lowest quintile (RR, 1.35; 95% CI, 0.97-1.90)], but not after adding processed meat to the model [highest versus lowest quintile (RR, 1.11; 95% CI, 0.75-1.65)]. We did not find any evidence for a protective association between prudent pattern and risk of prostate cancer. The lack of association between a western dietary pattern as identified by factor analysis in our cohort and prostate cancer risk suggests that dietary risk factors for prostate cancer are likely to differ from those for other conditions, such as cardiovascular disease and type 2 diabetes, that have been associated with a western dietary pattern in this cohort.