Ultra-processed foods and risk of declined renal function: a dose-response meta-analysis of 786,216 participants.

Objectives: Earlier investigations have documented an association between elevated consumption of Ultra-Processed Foods (UPFs) and adverse renal outcomes. To explore this relationship further, we executed a comprehensive dose-response meta-analysis to examine the link between UPFs intake and the risk of declined renal function.

Setting: A systematic search was completed utilizing the ISI Web of Science, Scopus, Embase as well as PubMed/MEDLINE databases (without any restrictions), up until September 5, 2024. Effect sizes of declined renal function were recalculated by applying a random effects model. The GRADE tool was adopted to assess the certainty of the evidence, while study quality and potential publication bias were examined via validated methods such as the Newcastle-Ottawa Scale, Egger's regression asymmetry and Begg's rank correlation test.

Results: Thirty-three studies (comprising 786,216 participants) were incorporated in the quantitative analysis. The results demonstrated that a greater UPFs intake was significantly associated with an enhanced risk of declined renal function (RR = 1.16; 95% CI: 1.09, 1.23; I² = 68.8%; p < 0.001; n = 37). Additionally, we observed that each 1-serving-per-day increase in UPFs consumption was associated to a 5% greater risk of reduced renal function (RR = 1.05; 95% CI: 1.02, 1.09; I² = 80.9%; p = 0.013; n = 9). A positive, linear association between UPF intake and the risk of declined renal function (P_nonlinearity = 0.107, P_{dose-response} < 0.001) was further displayed in the non-linear dose-response analysis.

Conclusion: Greater exposure to UPFs is positively associated with the risk of declined renal function. The information emphasizes the importance of considering UPFs in the prevention and management of adverse renal outcomes.