Whether diabetes and genetic susceptibility of kidney diseases modifies the relationship between ultra-processed foods (UPF) consumption and incident chronic kidney disease (CKD) remains uncertain. We aimed to investigate the association between UPF consumption and new-onset CKD in participants with and without diabetes, and explore whether genetic risks of kidney diseases may modify the association.

153,985 participants who were free of CKD at baseline and provided 24-h dietary recalls in the UK Biobank were included. UPF was defined according to the NOVA classification. The energy contribution of UPF was calculated by dividing the energy intake of UPF by the total energy intake. The study outcome was new-onset CKD, ascertained by self-report data and data linkage with primary care, hospital admissions, and death registry records.

During a median follow-up of 12.1 years, 4,058 participants developed new-onset CKD. There was a significant positive association between UPF consumption and new-onset CKD in total participants (per 10% increment, adjusted hazard ratio (HR) 1.04; 95% confidence interval (CI) [1.01;1.06]. The positive association between UPF consumption and risk of new-onset CKD was significantly stronger in participants with diabetes (per 10% increment, adjusted HR 1.11 [1.05;1.17]) than in those without diabetes (per 10% increment, adjusted HR 1.03 [1.00;1.05]; P-interaction = 0.005). Genetic risks of kidney diseases did not significantly modify the positive association in those with or without diabetes (all P-interactions > 0.05).

There was a significantly stronger positive association between UPF consumption and new-onset CKD in participants with diabetes compared with those without diabetes.