Consumption of a sourdough-leavened croissant enriched with a blend of fibers influences fasting blood glucose in a randomized controlled trial in healthy subjects.

BACKGROUND

An incorrect lifestyle, including diet, is responsible for the worldwide dramatic increase in obesity and type 2-diabetes. Increasing dietary fiber consumption may lead to health benefits and reformulation of bakery products may be a strategy to globally improve the diet.

OBJECTIVE

This study aimed to assess the impact of a two-week breakfast consumption with a sourdough-leavened croissant containing a blend of dietary fiber from 10 sources (4.8g/100g, FIBCRO), compared to a control croissant (dietary fibers 1.3g/100g, CONCRO) on daily energy intake, appetite, metabolic variables, and the gut microbiome.

METHODS

Thirty-two healthy participants were randomly allocated in two groups consuming FIBCRO or CONCRO. Participants self-recorded their diet and appetite through 7-day weighted food diaries and visual analogue scales every day over the two weeks. At baseline and after the intervention, fasting blood and urine samples, and fecal samples were collected beside blood pressure, anthropometry, and body composition. Serum glucose, lipids, C-reactive protein, and insulin according to the official methods and serum dipeptidyl peptidase-4 (DPPIV) activity by photometric method were measured. Polyphenols and urolithins in urines were analyzed by LC/MS/MS whereas gut microbiome in feces by shotgun metagenomics.

RESULTS

FIBCRO consumption improved fasting blood glucose compared to CONCRO (mean changes from baseline -2.0 mg/dL in FIBCRO vs +3.1 mg/dL in CONCRO, p=0.022), also reducing serum DPPIV activity by 1.7 IU/L (p=0.01) and increasing urinary excretion of urolithin A-sulfate by 6.9 ng/mg creatinine (p=0.04) compared to baseline. No further changes in any of monitored variables or in the gut microbiome were detected.

CONCLUSIONS

Results suggested that a two-week consumption of a sourdough croissant claimed as "source of dietary fiber" improved fasting glycemia compared to a conventional sourdough croissant in healthy subjects. The reduced serum DPPIV activity and increased bioavailability of urolithin likely contributed to determine that effect independently from gut microbiome changes.

CLINICAL TRIAL REGISTRY NUMBER AND WEBSITE WHERE IT WAS OBTAINED

NCT04999280 (https://clinicaltrials.gov/).

Informations de copyright

Copyright © 2024. Published by Elsevier Inc.

Déclaration de conflit d'intérêts

Declaration of Competing Interest ☒ The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.