Nutritional Composition Of Stool Donors' Diets Relative To That Of The Us Population: Results From 44 Donors From An International Stool Bank For Fecal Microbiota Transplantation

Introduction: Fecal microbiota transplantation (FMT) is a promising therapy for recurrent Clostridium difficile infection (CDI). Stool banks have emerged to catalyze widespread adoption and employ stringent screening criteria to find healthy donors. Dietary fats, fiber, and carbohydrates modulate fecal bile acids, which impact Clostridium difficile spore germination. FMT is thought to normalize colonic bile acids; however, there is a paucity of data examining the diet of stool donors compared to the U.S. population. Methods: We administered 46 Harvard Food Frequency Questionnaires (FFQs) to stool donors between August 17, 2015 and March 29, 2016. Donors undergo a rigorous 178-point clinical assessment for infectious and microbiome-mediated conditions, including an assessment of restrictive diets (e.g. Atkins, Paleo, and juice cleanses). Additionally, donors undergo dual testing of 30 laboratory investigations. Overall, only 2.8% of candidate qualify. Descriptive statistics were calculated and compared against the 2011-12 National Health and Nutrition Examination Survey (NHANES). Four participants were excluded from analyses for outlying, estimated caloric intake (4000 kcal/day). There were 42 donors included in final analyses. Results: Amongst the cohort, 62% (n=26) of donors were male. Donors had a mean age of 28.6 years, mean body mass index (BMI) of 23.2 kg/m2, and mean waist circumference of 32.4 inches in males and 29.0 inches in females. Overall, mean caloric, total fat, carbohydrate, protein, alcohol, and cholesterol intake of donors did not differ significantly from that of the U.S. population (Table 1). However, more dietary fiber was consumed by stool donors than by the U.S. population (26.3g/day for donors vs. 18.1g/day for U.S. population; p =0.028). Conclusion: Overall, dietary consumption of macro and micronutrients, including total fats and carbohydrates, of stool bank donors is similar to the average U.S. population. Of note, stool donors consume more fiber compared to the U.S. population. Given the role of fiber on fecal bile acids, an exploration assessing if differential fiber intake impacts the rate of FMT clinical cure in recurrent CDI is warranted.Figure 1