Healthy eating index and kidney function in adults: findings from the Ravansar non-communicable disease cohort

The global burden of chronic kidney disease (CKD) is increasing, driven largely by risk factors such as hypertension and diabetes. Modifiable lifestyle factors, particularly diet, may play a key role in renal health. This study aimed to investigate the association between diet quality, assessed by the Healthy Eating Index-2015 (HEI-2015), and kidney function in a large sample of Iranian adults from the general population.

This cross-sectional analysis used baseline data from the Ravansar Non-Communicable Diseases (RaNCD) cohort study, involving 8,787 adults aged 35-65 years. Dietary intake was assessed using a validated Food Frequency Questionnaire (FFQ), and diet quality was calculated using the HEI-2015. Kidney function was determined by estimating the glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease (MDRD) study equation. The association between HEI-2015 quartiles and the odds of reduced eGFR (defined as < 60 mL/min/1.73 m²) was examined using logistic regression.

Among the participants, 46.97% were men. A significant, inverse, dose-response association was observed between HEI-2015 scores and the odds of reduced eGFR. In the fully adjusted model, participants in the highest HEI quartile had 55% lower odds of reduced eGFR compared to those in the lowest quartile (OR: 0.45; 95% CI: 0.36, 0.58). Dietary analysis showed that individuals with preserved kidney function consumed significantly more fruits, vegetables, and seafood, but less sodium and added sugars (P < 0.05).

Higher diet quality, as measured by the HEI-2015, is significantly associated with better kidney function and lower odds of reduced eGFR. These findings highlight the potential for dietary interventions that promote overall healthy eating patterns to contribute to the primary prevention of CKD.

Not applicable.