O041 - MICROBIOME-GUIDED PERSONALIZED FIBER INTERVENTION IMPROVES INSULIN SENSITIVITY AND WEIGHT CONTROL IN ADULTS AT RISK FOR DIABETES

O041

MICROBIOME-GUIDED PERSONALIZED FIBER INTERVENTION IMPROVES INSULIN SENSITIVITY AND WEIGHT CONTROL IN ADULTS AT RISK FOR DIABETES

N. Hamari^1,*, G. Larik¹, M. M. Sost², C. V. Kalkeren¹, G. Galazzo³, J. Penders³, E. Blaak¹, E. Canfora¹

¹Human Biology, Institute of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Center +, Maastricht, ²Maastricht University-Campus , Centre for Healthy Eating & Food Innovation (HEFI), Venlo, ³Medical Microbiology, Infectious Diseases & Infection Prevention, Institute of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Center +, Maastricht, Netherlands

Rationale: The gut microbiota ferments dietary fibres into short-chain fatty acids (SCFAs) that influence host metabolism. However, long-term supplementation of single fibres has shown inconsistent effects, likely due to individual differences in the microbial fermentation capacity and SCFA production. This study investigated whether personalized fibre mixtures (PFM), designed to enhance gut microbial SCFA production, improve insulin sensitivity.

Methods: This randomized, placebo-controlled trial included 44 adults (BMI 28–40, aged 35–70) with prediabetes and/or insulin resistance. Anaerobic fecal samples were used to identify a fibre mixture that maximizes SCFA production using an in vitro colon model (TIM-2). Participants received either 24 g of the selected fibre mixture (n=22) or a control fibre (galacto-oligosaccharides, n=22) for 12 weeks. The primary outcome was insulin sensitivity measured by a hyperinsulinemic–euglycemic clamp, while secondary outcomes included energy expenditure, body composition, blood biomarkers, and microbial metabolites.

Results: No differences in peripheral insulin sensitivity (M-value) were observed between the groups. However, PFM decreased fasting plasma insulin levels (Δ -0.98 ± 2.48 vs 0.90 ± 2.96 uIU/mL, P=0.037), HOMA-IR (Δ -0.27 ± 0.65 vs Δ 0.22 ± 0.76, P=0.036), body weight (Δ -0.28 ± 2.3 vs Δ 1.37 ± 1.5 kg, P=0.014), and BMI (P=0.017) with a trend toward reduced body fat mass (P=0.073) compared to control. No differences were observed in energy expenditure, substrate oxidation, blood lipids, inflammatory markers, gut-derived hormones, gut microbiota composition and SCFAs.

Conclusion: While PFM did not improve peripheral insulin sensitivity, it modestly reduced body weight and HOMA-IR, suggesting benefits for hepatic insulin sensitivity. Personalized fibre approaches may improve metabolic health in those at risk for type 2 diabetes.

Disclosure of Interest: None declared