FMT offers no weight loss benefits in individuals with obesity

For individuals with obesity who are scheduled to undergo bariatric surgery, faecal microbiota transplantation (FMT) from a lean donor does not appear to help reduce weight before or after the procedure, according to a study.

The study included 41 patients (mean age 48.7 years, 71.1 percent female) with severe obesity (mean body mass index 42.5 kg/m²). They were randomized to receive FMT from either a lean donor (n=21) or from themselves (autologous placebo; n=20), delivered via gastroscopy into the duodenum.

Six months following FMT, 38 patients underwent bariatric surgery using laparoscopic Roux-en-Y gastric bypass (LRYGB; n=34) or laparoscopic sleeve gastrectomy (LSG; n=4). A total of 34 patients (82.9 percent) attended the last visit 18 months after the baseline visit.

The primary endpoint of weight reduction, assessed as the percentage of total weight loss (TWL), was substantial in both FMT and placebo groups at 6 months (4.8 percent, 95 percent confidence interval [CI], 2.7–7.0 and 4.6 percent, 95 percent CI, 1.5–7.6; p<0.001 and p=0.006, respectively). However, there was no significant difference observed between the two groups.

Likewise, TWL at 18 months, that is 12 months after surgery, further increased in both FMT and placebo groups (25.3 percent, 95 percent CI, 19.5–31.1 and 25.2 percent, 95 percent CI, 20.2–30.3; p<0.001 for both), with no significant between-group difference.

There were no major adverse events recorded.