Postprandial Hyperglycemia
Conditions
Keywords
Polyphenol, Fruit, Metabolic
Brief summary
Raised blood glucose levels can lead to adverse modifications to functional proteins within the body and eventually lead to the development of type 2 diabetes. Fruit polyphenols may help to control glycaemia following a carbohydrate meal or beverage. The aim of this study is to investigate the effects of blackcurrant (BC) and apple (A) extracts on postprandial glycaemia, insulinaemia and plasma gastric inhibitory polypeptide concentrations following a mixed carbohydrate test meal.
Detailed description
Introduction: Diets with a high glycaemic load (a measure of the overall blood glucose-raising effect of a serving of a food) and containing high amounts of non-milk extrinsic sugars may contribute towards increased risk of developing type 2 diabetes (T2D). Raised blood glucose levels can lead to adverse modifications to functional proteins within the body and eventually lead to the development of T2D. Large peaks in blood glucose after a meal are a risk factor for T2D, and therefore it is desirable to consume a diet that will allow more gradual rises in blood glucose levels after meals. Fruit polyphenols may help to control glycaemia following a carbohydrate meal or beverage. Possible mechanisms include inhibition of intestinal enzymes and inhibition of intestinal glucose absorption by decreasing SGLT1/GLUT2 transport activity. The scientific literature also suggests that foods rich in polyphenols exert beneficial effects on risk factors of cardiovascular disease such as hypertension, lipid metabolism and vascular function. Study Design: A randomised, controlled, double-blind, cross-over study will be conducted. Subjects will receive combined blackcurrant and apple polyphenols, apple polyphenols only or placebo in random order at 3 separate study visits immediately before a high-carbohydrate meal. Seven days wash-out period will be required between study days.Standardised diet and exercise advice will be given prior to the visit. Subjects will arrive on each study visit between 09.00 and 10.00 h, after a 12 h overnight fast. They will then be cannulated in a forearm vein and baseline fasting blood samples will be taken in duplicate. All test drinks will be blended to be equal in volume, macronutrient and energy content. Fruit extracts instead of whole fruits will be administered to avoid the confounding effect of fruit fibre/viscosity on gastric emptying rate. Following consumption of the test drink, the high carbohydrate meal (starch and sucrose) will be served (white bread with apricot jam). Outcome variables will be measured postprandially until 120 min post-meal.
Interventions
DIETARY_SUPPLEMENTPolyphenols
Drinks will be delivered in random order at 3 separate study visits immediately before a high-carbohydrate meal. Seven days wash-out period will be required between study days.
Sponsors
King's College London
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
20 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Age: 20-60 y * Male and female (post-menopausal only) * Healthy (free of diagnosed diseases in the
Exclusion criteria
) * BMI 18-35 kg/m2 * Able to understand the information sheet and willing to comply with study protocol * Able to give informed written consent
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Postprandial glycaemia | baseline and 10, 20, 30, 45, 60, 75, 90 and 120 min following the test drink. | Peak postprandial plasma glucose concentrations (Cmax) t +0-30 min and change from baseline data and areas over baseline t+0-30 min and t+0-120 min |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Postprandial glucose-dependent insulinotropic polypeptide (GIP) concentrations | baseline and 10, 20, 30, 45, 60, 75, 90 and 120 min following the test drink. | Peak postprandial GIP concentrations (Cmax) t +0-30 min and change from baseline data and areas over baseline t+0-30 min and t+0-120 min |
| Postprandial glucagon-like peptide-1 (GLP-1) concentrations | baseline and 10, 20, 30, 45, 60, 75, 90 and 120 min following the test drink. | Peak postprandial GLP-1 concentrations (Cmax) t +0-30 min and change from baseline data and areas over baseline t+0-30 min and t+0-120 min |
| Blood pressure | baseline and 60, 90 and 120 min following the test drink. | Change in the blood pressure after consumption of test drink |
| Postprandial insulinaemia | baseline and 10, 20, 30, 45, 60, 75, 90 and 120 min following the test drink. | Peak postprandial insulin concentrations (Cmax) t +0-30 min and change from baseline data and areas over baseline t+0-30 min and t+0-120 min |
| Plasma non-esterified fatty acids (NEFA) | baseline and 10, 20, 30, 45, 60, 75, 90 and 120 min following the test drink. | Peak postprandial NEFA concentrations (Cmax) t +0-30 min and change from baseline data and areas over baseline t+0-30 min and t+0-120 min |
| Plasma triglycerides (TAG) | baseline and 10, 20, 30, 45, 60, 75, 90 and 120 min following the test drink. | Peak postprandial TAG concentrations (Cmax) t +0-30 min and change from baseline data and areas over baseline t+0-30 min and t+0-120 min |
| Vascular function (Digital Volume Pulse; DVP) | baseline and 60, 90 and 120 min following the test drink. | Change in the tone of larger arteries (stiffness index) and small to medium-sized arteries (reflection index). |
Countries
United Kingdom
Outcome results
None listed