Investigating the Effects of Mycoprotein and Guar Gum on Glycemic Control in people with Type 2 Diabetes: A Double-Blind Randomized Controlled Trial

Abstract BACKGROUND/OBJECTIVE: Type 2 diabetes (T2D) is highly prevalent worldwide, particularly in south Asia, and diet is the first- line strategy to manage postprandial glucose (PG). Mycoprotein (MP) and guar gum (GG) independently reduce PG in T2D, but there is no evidence on the combination. This study investigates the effect of MP and GG on PG, postprandial insulin and appetite in people with T2D. METHODS/SUBJECTS: in this randomized, double-blind crossover-design acute trial. 24 subjects with T2D, were randomly allocated to soy, chicken, and MP with and without GG-enriched chapati and attended 6-study visits. The incremental area under the curve (iAUC 0 − 180 ) for PG, insulin, glucagon-like peptide-1 (GLP-1), peptide tyrosine-tyrosine (PYY), subjective appetite, ad libitum and 48h-post-visit energy intake were measured. Outcomes were analyzed by linear mixed model with fixed effects of protein, GG and ethnicity. RESULTS For PG iAUC 0 − 180 , a main effect of protein, GG and ethnicity ( p < 0.01 for all) was shown, where MP led to -28% [95% CI -219, -41] mmol/L·min, p < 0.001 vs. chicken; GG led to -40% [-239, -127] mmol/L·min, p < 0.001 vs. no-GG; South Asians had + 43% [85, 323] mmol/L·min, p < 0.001 vs. white Europeans. For insulin iAUC 0 − 180 , a main effect of protein ( p = 0.04), bread ( p < 0.01) was found, without post-hoc significances. An interaction effect was found ( p = 0.01) for insulin iAUC 0 − 180 between GG and south Asian. CONCLUSIONS In T2D, MP and GG significantly lowered PG, without any interaction effect. South Asians have significantly increased PG vs. white Europeans.