New data from an analysis of nearly 10,000 patients suggests switching to a greener diet could help lower a patient’s risk of developing urinary tract infections (UTI).

Results of the study, which examined a cohort of 9724 Taiwanese patients, found a vegetarian diet was associated with a 16% lower overall risk of developing a UTI compared to non-vegetarians—also noting this apparent effect was stronger in men than in women.

To test their hypothesis that a vegetarian diet could decrease a patient’s risk of developing a UTI, investigators from the Hualien Tzu Chi Hospital conducted an analysis of patients from the Tzu Chi Vegetarian Study—a prospective cohort study that included more than 12000 participants from communities in Taiwan. From this population, investigators included a cohort of 9724 patients—all of which were 20 or older and were UTI free prior to the start of the study.

All patients included in the current analysis were followed from 2005 to 2014 and assessments of their disease status were performed through queries of the National Health Insurance Research Database and the National Health and Welfare Data Science Center. Assessments of the patients' dietary habits were performed through a 57-item food frequency questionnaire that was part of the Nutrition and Health Survey in Taiwan—investigators classified participants as vegetarian if they self-identified as vegetarians or if they reported “no eating” in frequency questions related to individual meat and fish items in the questionnaire.

Using data from the Tzu Chi Vegetarian Study, investigators obtained information relating to the participants' demographics, education level, medical history, and lifestyle habits—such as diet, physical activity, and other information about other modifiable risk factors. Due to the study population being made up of by Buddhists, investigators point out volunteers were currently non-smokers and did not consume alcohol.

Upon analysis, the overall ratio of non-vegetarians to vegetarians was about 2:1 and the vegetarian group was older, had a higher proportion of female participants, had received less education, and was less likely to have a history of smoking or alcohol-drinking. Additionally, the vegetarian group had a significantly lower proportion of individuals with hypertension, diabetes, hyperlipidemia, and comorbid conditions that would predispose them to UTIs.

During the 10-year follow-up period, 661 individuals were diagnosed with a UTI. Results of the investigators’ analyses revealed the UTI risk among vegetarians was significantly lower than the risk observed among non-vegetarians (HR 0.84; 95% CI, 0.71—0.99, P=0.038). Overall, 217 of the 3040 vegetarians developed a UTI compared to 444 cases among the 6684 non-vegetarians.

When examining potential risk factors, results indicated age, female, diabetes, urine retention, and renal failure were associated with significant increases in the risk of UTI. Additionally, hypertension, urinary obstruction, urolithiasis, and immune dysfunction were associated with non-significant increases in UTI risk.

This study, “The risk of urinary tract infection in vegetarians and non-vegetarians: a prospective study,” was published online in Scientific Reports.