The Effects of a Whey Protein and Guar Gum-Containing Preload on Gastric Emptying, Glycaemia, Small Intestinal Absorption and Blood Pressure in Healthy Older Subjects.

Hung Pham,Karen L Jones,Lian Q Huynh,Trygve Hausken,Christopher K Rayner,Michael Horowitz,Iselin S Holen,Seva Hatzinikolas,Tongzhi Wu,Liza K Phillips

doi:10.3390/nu11112666

Hung Pham, Karen L Jones + Show 8 more

Open Access

https://doi.org/10.3390/nu11112666

Copy DOI

Abstract

A whey protein/guar gum preload reduces postprandial glycaemia in type 2 diabetes through slowing gastric emptying. However, gastric emptying has previously been assessed using a stable isotope breath test technique, which cannot discriminate between slowing of gastric emptying and small intestinal absorption. This preload also may be useful in the management of postprandial hypotension. We evaluated the effects of a whey protein/guar preload on gastric emptying, glucose absorption, glycaemic/insulinaemic and blood pressure (BP) responses to an oral glucose load. Eighteen healthy older participants underwent measurements of gastric emptying (scintigraphy), plasma glucose and insulin, glucose absorption, superior mesenteric artery (SMA) flow, BP and heart rate (HR) after ingesting a 50 g glucose drink, with or without the preload. The preload reduced plasma glucose (p = 0.02) and serum 3-O-methylglucose (3-OMG) (p = 0.003), and increased plasma insulin (p = 0.03). There was no difference in gastric emptying or BP between the two days. The reduction in plasma glucose on the preload day was related to the reduction in glucose absorption (r = 0.71, p = 0.002). In conclusion, the glucose-lowering effect of the preload may relate to delayed small intestinal glucose absorption and insulin stimulation, rather than slowing of gastric emptying.

Highlights

The use of a macronutrient preload given 15–30 min before a main meal—to diminish postprandial glycaemic excursions, represents a novel approach to manage type 2 diabetes (T2D) [1,2,3,4].The underlying rationale is that the nutrients in the preload will stimulate the release of gut hormones, including glucagon-like peptide-1 (GLP-1), to augment insulin secretion and slow gastric emptying of the subsequent meal [5]
We have shown that the fall in blood pressure (BP) after a meal is greater when the rate of gastric emptying is faster in both healthy older subjects [14,15] and patients with T2D [16], while slowing gastric emptying with guar gum attenuates the fall [17,18]
Paired BP, heart rate (HR), superior mesenteric artery (SMA) blood flow, plasma glucose and insulin data were available in 18 subjects, while gastric emptying and serum 3-OMG data were available in 17 subjects

Summary

Introduction

The use of a macronutrient preload given 15–30 min before a main meal—to diminish postprandial glycaemic excursions, represents a novel approach to manage type 2 diabetes (T2D) [1,2,3,4].The underlying rationale is that the nutrients in the preload will stimulate the release of gut hormones, including glucagon-like peptide-1 (GLP-1), to augment insulin secretion and slow gastric emptying of the subsequent meal [5]. Whey protein (a by-product in the production of cheese) and guar gum (a viscous, soluble polysaccharide, commonly used as a food thickener) have both been associated with the slowing of gastric emptying [2,4]. In those studies, the preload was well-tolerated when taken twice a day and substantially reduced the blood glucose response to a mashed potato meal, and modestly decreased glycated haemoglobin (0.1%) in

Objectives

Methods

Results

Discussion

Conclusion