Investigating the effects of mycoprotein and guar gum on postprandial glucose in type 2 diabetes: a double-blind randomised controlled trial.

BACKGROUND

Type 2 diabetes (T2D) is highly prevalent, particularly among south Asian populations, and diet is the first-line strategy to manage postprandial glucose (PG) response. Mycoprotein and guar gum reduce PG in normo-glycaemic people. This study investigates the independent and interactive effects of mycoprotein and guar gum on PG, insulin and appetite responses in white Europeans and south Asians with T2D.

METHODS

In this double-blind, crossover, acute, randomised controlled trial, 18 subjects with T2D (10 white European, 8 south Asian) completed six separate visits consuming soy, chicken, and mycoprotein with and without guar gum. Incremental area under the curve (iAUC) for PG, insulin, and appetite scores, and total AUC glucagon-like peptide-1 (GLP-1), peptide tyrosine-tyrosine (PYY), as well as ad libitum energy intake and 48h-post-visit energy intake were measured and analysed by linear mixed models with protein, guar gum and ethnicity as fixed effects.

RESULTS

We found independent effects of mycoprotein, guar gum and ethnicity on PG iAUC (mmol/L·min), where mycoprotein reduced PG vs. chicken (-129.84 [95% CI -203.16, -56.51]; p = 0.002), guar gum reduced PG vs. no guar gum (-197.35 [95% CI -254.30, -140.40; p < 0.001], and south Asian had increased PG vs. white Europeans (195.75 [95% CI 66.14, 325.35]; p = 0.005). An interaction between guar gum and ethnicity (p < 0.015) was found for insulin iAUC (µUI/mL·min), with guar gum lowering insulin responses in south Asian participants (-1909.69 [95% CI -2834.83, -984.511]; p < 0.001). No independent or interactive effects were observed for appetite-related outcomes.

CONCLUSION

Mycoprotein and guar gum promote significant independent effects in lowering PG in both white European and south Asians with T2D.