Certain gut microbiota–related metabolites appear to predict the response to weight loss treatment, researchers concluded after conducting a study involving 510 individuals. Participants who were overweight or obese were randomly assigned to 1 of 4 diets. Investigators looked at the link between 6-month change in specific gut microbiota–related metabolites with body weight (BW), waist circumference (WC), body fat composition, fat distribution, and resting energy expenditure (REE) improvements. Among the results:

• Individuals with a greater choline and l-carnitine reductions experienced significant BW and WC loss; those with greater decreases of trimethylamine N-oxide did not.
• Choline reduction significantly predicted decreased body fat composition, fat distribution, and REE.
• Hyperglycemia was present in 3 in every 10 patients, but it did not modify the associations.
• Fasting glucose levels did not impact the correlations either.
• Patients with choline increases were more than twice as likely to fail to lose weight at 2 years.
• Those with l-carnitine increases 77% more likely to fail to do so.