Milk with Mulberry Leaf Extract, Vegetable Oil, and Inulin Reduce Early Glucose and Insulin Response in Healthy Adults in China: Randomized Controlled Trial

Abstract

Background

High carbohydrate intake leading to increased postprandial glycemia is associated with type 2 diabetes. Particularly in China, prediabetes is highly prevalent (>40%) in adults (>40 y old). Bioactive ingredients such as mulberry leaf extract (MLE) lower glycemia and can be a good strategy to manage prediabetes, but its health effects when added to milk are poorly understood.

Objectives

This study aimed to investigate the effect of a milk powder supplemented with MLE, vegetable oil, and inulin on glucose and insulin responses to a carbohydrate-rich meal compared with regular skimmed milk, in healthy middle-aged adults.

Methods

A 2-arm, crossover, open-label, randomized controlled trial with 31 healthy adults (>45 y old) consuming either the supplemented milk (test product [TP]) or regular skimmed milk (control) with a standardized breakfast. Blood samples were collected to assess postprandial responses.

Results

Twenty-eight subjects were analyzed. TP did not change glucose incremental area under the curve (iAUC0)-180 min (primary outcome) but significantly decreased glucose iAUC0-60 min by 25% compared with control. TP also significantly decreased insulin and c-peptide iAUC0-60 min by 22% and 18%, respectively, and for iAUC0-120 min by 16% and 11%, respectively. Plasma glucose-dependent insulinotropic polypeptide iAUC0-120 min and 0–180 min were also significantly decreased.

Conclusions

As compared with regular skimmed milk, milk supplemented with MLE, vegetable oil, and inulin reduced early postprandial glucose and insulin responses in healthy adults of Chinese ethnicity, which could mitigate the risk of developing chronic diseases.

This study was registered at clinicaltrials.gov as NCT05570435.