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

Background: Nutrients have been associated with renal cell carcinoma (RCC), however results regarding the specific nutrients involved are inconsistent. The present study used a case-control design to evaluate the role of nutrients 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 total energy consumption. Results: Cases and controls did not differ in the mean number of calories consumed daily. However, high consumption of fat increased risk for RCC (>65 grams OR: 1.62, 95% CI: 1.1, 2.4). Protective associations were found for numerous vitamins including vitamins A, C and K. Vitamin K provided the greatest protection (OR: 0.88, 95% CI: 0.80, 0.97 per 100 micrograms). Various minerals also demonstrated protective associations with RCC, including calcium, folate, magnesium, potassium and zinc. Magnesium provided the greatest protection (OR: 0.72, 95% CI: 0.60, 0.87 per 100 milligrams). Significant direct trends were observed for all vitamins and minerals. Results varied by sex and race. Discussion: Increases in incidence of RCC cannot fully be explained by better detection. This study provides further evidence of nutrient correlates of RCC. The results provide support for many associations of nutrients and RCC previously reported, as well as suggest new associations.