Dietary patterns and renal cell carcinoma: Results from a case-control study

Background: Diet has been associated with renal cell carcinoma (RCC), however the specific food types involved remain controversial. The present study used a case-control design to evaluate the role of dietary patterns on RCC risk. Methods: Incident cases of RCC were identified from the Florida Cancer Data System, and population controls were identified from random-digit dialing. In-person interviews were conducted among 335 cases and 337 controls using a standardized food questionnaire. Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI). All analyses were controlled for age, sex, race, smoking, body mass index (BMI) and income. Results: Significant associations were found between various food items and RCC. Among the total population, eating four or more servings of vegetables daily significantly reduced risk of RCC (OR: 0.60; 95% CI: 0.43, 0.82). Eating red meat once a week or more significantly increased RCC risk (OR: 1.80, 95% CI: 1.24, 2.60). Consumption of three or more servings of fat daily increased RCC risk by 70% (OR: 1.70, 95% CI: 1.19, 2.43). Significant direct trends in risk were observed among many of food items, including various meats, vegetables, grains and fats. Results varied by sex and race. Discussion: Continued increases in incidence of RCC cannot fully be explained by better detection, especially among African-Americans. The findings of this study provide further evidence of dietary correlates of RCC. Specifically, a diet low in vegetables and high in red meat and fat consumption may have an unfavorable role on RCC.