OBJECTIVE: To determine if female vegetarians and vegans have a lower rate of recurrent UTI (rUTI) compared to non-vegetarians, as different strains of bacteria may colonize the gut based on dietary factors, with less virulent strains in those who eat a plant-based diet. METHODS: We performed a cross-sectional study of participants in the Adventist Health Study-2 (AHS-2) from whom detailed dietary and urinary history were collected. Participants were classified as vegan, lacto-ovo-vegetarian, pesco-vegetarian, and non-vegetarian. Within the AHS-2 study, there was also an assessment of UTI history. Other variables included were: age, BMI, race, diabetes and menopausal status. RESULTS: 57,252 women had complete data. Average age was 58 years. More than half (53.7%) of participants were non-vegetarian, 28.5% lacto-ovo-vegetarian, 10.3% pesco-vegetarian and 7.5% vegan. A history of rUTI was reported by 13.1%. Risk of rUTI increased with age, non-Black race, higher BMI, diabetes and menopause. The rate of reported rUTI significantly varied with diet: the highest prevalence of rUTI was in non-vegetarians (14.2%), followed by pesco-vegetarians (13.5%), lacto-ovo-vegetarians (11.6%) and vegans (10.3%, p<.001). On multivariate regression, age, race, diabetes and menopause remained significant factors associated with rUTI. Additionally, diet maintained a statistically significant association with rUTI, with lacto-ovo-vegetarians and vegans at lower risk than pesco-vegetarians and non-vegetarians. CONCLUSIONS: Compared to nonvegetarians, lacto-ovo-vegetarians and vegans have a 23% and 31% lower association of rUTI. In an age of increasing bacterial resistance, non-antibiotic prophylactic interventions with dietary modification to a more plant-based diet may add to the armamentarium for managing rUTI.
Comiter et al. (Mon,) studied this question.