Consumption of fruits and vegetables and risk of renal cell carcinoma: a meta-analysis of observational studies

Abstract

BackgroundThere have been inconsistent results about the association between consumption of fruits and vegetables and renal cell carcinoma (RCC) risk. We conducted a meta-analysis of the published observational studies to explore this association.ResultsNineteen observational studies (4 cohort, 1 pooled and 14 case-control studies), involving 10,215 subjects with RCC were part of this meta-analysis. The SRR for the highest vs. the lowest intake of vegetables was 0.73 (95% CI: 0.63–0.85; Pheterogeneity = 0.004, I2 = 53.5%), whereas for fruits it was 0.86 (95% CI: 0.75–0.98; Pheterogeneity = 0.012, I2 = 47.4%). Linear dose-response analysis also showed similar results, e.g., for per 1 serving/day increment of vegetables, the SRR was 0.90 (95% CI: 0.84–0.96) and for fruits it was 0.97 (95% CI: 0.93–1.01). Nonlinear association was only observed for vegetables (Pnonlinearity = 0.001), but not for fruits (Pnonlinearity = 0.221).Materials and MethodsEligible studies up to August 31, 2016 were identified and retrieved by searching MEDLINE and EMBASE databases along with manual review of the reference list from the retrieved studies. Quality of included studies was evaluated using Newcastle-Ottawa Quality Assessment Scale (NOS). Random-effects model was used to calculate summary relative risk (SRR) and corresponding 95% confidence interval (CI).ConclusionsThis meta-analysis indicated a protective effect of consumption of vegetables and fruits on RCC risk. Further studies are warranted with prospective designs that use validated questionnaires and control for important confounders.

The role of diet in renal cell carcinoma incidence: an umbrella review of meta-analyses of observational studies

“…We identified the following exposures associated with the incidence of RCC: healthy dietary pattern [ 64 ], unhealthy/Western pattern [ 64 ], drinking pattern [ 64 ], fish [ 65 ], total fat [ 87 ], sweetened carbonated beverage [ 66 ], beer [ 67 ], wine [ 67 ], spirits [ 67 ], riboflavin [ 68 ], vitamin B6 [ 68 ], folate [ 68 ], vitamin B12 [ 68 ], saturated fat [ 87 ], methionine [ 68 ], choline [ 68 ], betaine [ 68 ], all meats [ 15 ], tea [ 69 ], fruit fiber [ 70 ], vegetable fiber [ 70 ], cereal fiber [ 70 ], legume fiber [ 70 ], dietary inflammatory index [ 71 ], vitamin C [ 72 ], seafood [ 16 ], animal fat [ 16 ], cholesterol [ 16 ], total protein [ 87 ], animal protein [ 87 ], plant fat [ 16 ], plant protein [ 87 ], sweetened beverages (including artificially sweetened beverages and sugar-sweetened beverages) [ 73 ], polyunsaturated fat [ 87 ], vitamin E [ 74 ], coffee [ 75 ], vitamin D [ 76 ], dietary nitrate [ 77 ], dietary nitrite [ 77 ], glycemic index [ 78 ], glycemic load [ 78 ], monounsaturated fat [ 87 ], dietary fiber [ 78 ], alcohol (light) [ 79 ], alcohol (moderate) [ 79 ], alcohol (heavy) [ 79 ], alcohol (any) [ 79 ], vegetables [ 80 ], fruit [ 80 ], red meat [ 17 ], processed meat [ 17 ], cruciferous vegetables [ 81 ], poultry [ 15 , 16 ], fruit and non-starchy vegetables [ 87 ], non-starchy vegetables [ 87…”

“…Increasing vegetable consumption was found to be inversely related to RCC risk in our study. A meta-analysis conducted by Zhang et al found that the protective effect of vegetables was diminished after adjustment for body mass index [ 80 ], implying that obesity might be an important intermediate mechanism between vegetable consumption and the incidence of RCC. Obesity has been acknowledged by the guidelines of the European Association of Urology as a risk factor for RCC [ 146 ], which might be related to the inverse association between vegetables and obesity [ 147 – 151 ].…”

Fruits and vegetables consumption and the risk of gallstone diasease

“…A variety of chronic diseases have been studied with regard to FVs consumption, such as type 2 diabetes, [28] depression, [29] cardiovascular disease, [30,31] and cancers. [32,33] While eating more FVs has been showed to reduce the risk of all those disease, its association with gallstone disease still needs more studies.…”

Lifestyle in urology: Cancer

“…A high-fiber diet, for instance, has been associated with a lower incidence of RCC, while the high concentration of nitrite, present in processed meat, may increase the risk. [46][47][48][49] A higher incidence of RCC has been documented in women who consume large quantities of red meat and/or processed meat, with a greater increase among those in pre-menopausal period. 50,51 No association was found in the male population, nor in relation to white meat consumption, regardless of gender.…”