Background
Fecal microbiota transplantation (FMT) has been studied for the treatment of metabolic syndrome with varying success. However, the possibility of utilizing FMT to prevent metabolic syndrome is to date unknown.

Methods
Secondary analysis of a previously published double-blind, randomized, placebo-controlled pilot trial of FMT in obese metabolically healthy patients was conducted. Post-prandial glucose and insulin levels were measured (NCT02741518).

Results
A total of 22 patients were enrolled, 11 in each arm. There were no baseline differences in the area under the curve (AUC) of glucose or insulin in the FMT group compared to placebo. There was a significant change in glucose AUC at week 12 compared to baseline, and in the insulin AUC at week 6 compared to baseline in the FMT group vs. placebo (change in glucose AUC (mg/dl × 60 min): 579 vs 1978, p = 0.03) (change in insulin AUC (μU/ml × 60 min): 137 vs 2728, p = 0.01).

Conclusions
These data suggest that FMT may have a potential role in preventing the development of metabolic syndrome in patients with obesity.