Vegetarian Diet and Kidney Function in Women and Men From Different Ethnic Groups: The Healthy Life in an Urban Setting (HELIUS) Study

Objectives: A vegetarian diet may benefit kidney function. However, the sex-specific association of adherence to a vegetarian diet and change in kidney function, and its potential underlying mechanisms remain to be established. Methods: Our observational study included baseline and follow-up data on vegetarian diet adherence and estimated glomerular filtration rate (eGFR) from Dutch, South-Asian Surinamese, African Surinamese, Turkish, and Moroccan participants from Healthy Life in an Urban Setting, a multiethnic prospective cohort in Amsterdam. The median time between baseline and follow-up was 81 (70, 95) months. Vegetarian diet adherence was determined through a questionnaire and intake of dietary components was calculated using the food frequency questionnaire. The sex-specific association between vegetarian diet adherence and change in eGFR and albumin-creatinine ratio (ACR) was assessed with linear regression analysis. To explore whether associations were consistent by ethnic group, we stratified the groups of women and men by ethnicity. Results: Among 5,776 women and 4,443 men (median age: 48 [38, 55] and 48 [37, 56], respectively), the median eGFR was 102 (89, 112) and 101 (89, 111) at baseline and 92 (80, 104) and 93 (80, 103) at follow-up. We did not find an association between vegetarian diet adherence and eGFR or ACR change for both sexes. However, a 1 g/day higher fiber intake at baseline was associated with a lower decrease in eGFR of 0.10 (95% confidence interval [CI] 0.02, 0.17) in women and 0.07 (95% CI 0.00, 0.15) in men. Moreover, a 1 g/day higher intake of processed meat intake at baseline was associated with a 0.09 (95% CI 0.04, 0.14) higher increase in ACR in women. Conclusion: We found no evidence that vegetarian diet adherence was associated with a slower kidney function decline for both sexes across ethnic groups. Higher fiber intake and lower processed meat intake (women only) were associated with slower kidney function decline.