Dietary vitamin C, E, and carotenoid intake and risk of renal cell carcinoma

Object The study examines the association between dietary intake of vitamin C, E, and carotenoids and the risk of renal cell carcinoma (RCC). Methods Between 1994 and 1997 in 8 Canadian provinces, mailed questionnaires were completed by 1,138 incident, histologically confirmed cases of RCC and 5,039 population controls, including information on socio-economic status, lifestyle habits and diet. A 69-item food frequency questionnaire provided data on eating habits 2 years before data collection. Odds ratios (OR) and 95% confidence intervals (CI) were computed using unconditional logistic regression. Results Dietary intake of beta-carotene and lutein/zeaxanthin was inversely associated with the risk of RCC. The ORs for the highest versus the lowest quartile were 0.74 (95% CI, 0.59-0.92) and 0.77 (95% CI, 0.62-0.95), respectively. The significant inverse association with beta-carotene and lutein/zeaxanthin was more pronounced in women, and in overweight or obese subjects. The relation of lutein/zeaxanthin to RCC was stronger in ever smokers. No clear association was observed with vitamin C and E, beta-cryptozanthin, and lycopene. Conclusion The findings provide evidence that a diet rich in beta-carotene and lutein/zeaxanthin may play a role in RCC prevention.