Ovo-lactovegetarian diet as a possible protective factor against gallbladder polyps in Taiwan: A cross-sectional study

Objective: Gallbladder polyps (GBPs) are an increasingly common incidental finding and 3% to 8% of GBPs become malignant. A poor prognosis is expected in patients with gallbladder cancer. No studies have considered the relationship between diet and the development of GBPs in the Taiwanese population. The objective of this study was to investigate whether a vegetarian diet protects against GBP development. Materials and Methods: This cross-sectional study included 11,717 individuals who received a health checkup at Taipei Tzu Chi Hospital (New Taipei City, Taiwan) between October 2011 and October 2016. All individuals completed questionnaires that collected data about their characteristics, dietary patterns, and lifestyle. Physical examinations were conducted, and blood chemistry tests were performed. The presence of GBPs was determined using ultrasonography. We subsequently evaluated the association between diet and GBP prevalence using multivariate analysis. Results: The prevalence of GBPs for the entire group was 8.3%. GBPs were significantly less common in the vegetarian groups (vegans 9.0%, ovo-lacto vegetarians 7.5%, and semi-vegetarians 7.2%) compared with the omnivore group (9.6%) (P = 0.002). Step-wise logistic regression revealed that an ovo-lacto vegetarian diet was a possible protective factor (odds ratio = 0.83, P = 0.015). Conclusions: The study findings showed a strong negative association between an ovo-lacto vegetarian diet and GBP occurrence.