Daily profiles of plasma short-chain fatty acids after the intake of three different cereal fibers: a randomized controlled study

Purpose: To evaluate plasma short-chain fatty acids (SCFA) profiles after the acute intake of cereal fibers in overweight individuals. Methods: In a randomized, controlled cross-over study, twenty overweight/obese individuals, 30–75 years, consumed at one-week interval three products, each containing 11 g fiber (arabinoxylan (AX), wheat bran or cellulose) during a standard breakfast meal. Plasma samples were collected at fasting, for 8-h after breakfast and on the following morning. SCFAs were measured by LC–MS/MS. Results: Plasma acetate, propionate and butyrate increased after the three test fibers (p = 0.0001, time effect). The acetate peak was observed between 300 and 360 min after all test fibers (p < 0.05–0.003). Propionate increased significantly by 60 min after AX (p = 0.017) and wheat bran (p = 0.036) while butyrate increased only after AX (p = 0.038). A second peak was observed for propionate at 390 min after AX (p = 0.065) and wheat bran (p = 0.037) and for butyrate only after wheat bran (p = 0.024), remaining above baseline until the morning after. No significant difference was observed between the average daily plasma concentrations of acetate, propionate and butyrate. A very high inter- and intra-subjects’ variability of SCFA response was observed. Cluster analysis identified high and low SCFA producers after fiber ingestion among the study participants. Conclusions: After fiber ingestion plasma kinetics of acetate differ from those of butyrate and propionate. Among the tested fibers, AX and wheat bran show a better intestinal fermentation ability than cellulose. Heterogeneity in the fermentation ability exists among study participants, with half of them having a minimal SCFA increase after fiber ingestion. Clinical trial Registry number: NCT05443828; https://classic.clinicaltrials.gov/ct2/show/NCT05443828