LAUSR

Observational studies on the association between citrus fruit intake and risk of renal cell carcinoma (RCC) have reported inconsistent results. We quantitatively assessed this association by conducting a meta-analysis. PubMed and Embase databases search was conducted including relevant studies published up to January, 2020. We included epidemiological studies that reported relative risks (RRs) or odds ratios (ORs) with 95% confidence intervals (CIs) for the association between citrus fruit intake and RCC risk. A total of eight epidemiological studies consisting of five cohort and three case-control studies were included. The overall analysis showed a significantly reduced risk of RCC for high intake of citrus fruit (OR = 0.84, 95% CI 0.73-0.95). No heterogeneity was detected among the included studies (p = 0.497 for heterogeneity; I2  = 0). There was no significant publication bias by Begg's test (p = 0.266) or Egger's test (P = 0.578). A statistically significant association between citrus fruit intake and RCC was observed in case-control studies (OR = 0.84, 95% CI 0.71-0.98), while no association was observed in cohort studies (OR = 0.84, 95% CI 0.64-1.05). In addition, the dose-response analysis indicated that the RCC risk reduced by 13% (95%CI 1.0%-27%, p = 0.04 for heterogeneity) for each 100 grams per day increment of citrus fruit intake. In summary, our findings suggest an inverse association between citrus fruit intake and RCC incidence.