Konjac mannan oligosaccharides as a sustainer of fasting-associated gut microbiome signature after discontinuation of intermittent fasting in overweight individuals: A protocol for an open-label randomized clinical trial.

BACKGROUND

Our previous studies show that the improvement in cardiometabolic traits by intermittent fasting is associated with remodeling the gut microbiome, with short-chain fatty acids (SCFA) producing bacteria being evident. These effects, however, are largely lost when intermittent fasting is discontinued. Konjac mannan oligosaccharides (KMOS) are a commercial nature-deprived prebiotic, which has been reported to increase the levels of intestinal SCFA-producing bacteria. However, the capacity of continued KMOS consumption to maintain intermittent fasting-provoked levels of SCFA-producing bacteria, remains unknown.

METHODS

This study aims to test whether a KMOS supplement positively affects fasting-provoked SCFA-producing bacteria levels during, and in particularly, after discontinuation of intermittent fasting. This prospective, randomized, controlled trial will be conducted in overweight volunteers aged 18-65. All participants will perform one month of intermittent fasting followed by one month of an ad libitum diet. Participants will be randomly assigned to receive KMOS (1.5 g/d) during fasting, both during fasting and the subsequent ad libitum period, or neither. Primary outcomes will be relative abundance of SCFA-producing bacteria in fecal samples, as determined by 16s rRNA sequencing. Secondary outcomes will be changes in body weight, blood pressure, and serum lipid levels.

CONCLUSIONS

Findings from this trial will answer the question whether KMOS can maintain fasting-associated SCFA producer level and metabolic benefits when fasting is discontinued.

CLINICAL TRIAL REGISTRATION: ChiCTR2200058139.