Effects of Polyphenols Found in Pomegranate and Olives Food Supplements on Postprandial Blood Glucose in Vivo.

NCT02486978 | Completed DMC

• 1 other identifier: MEEC 14-029
• Study Type: interventional
• Target: 16
• Locations: 1 country
• Sites: 1

Brief Summary

Consumption of carbohydrate containing foods or sugary drinks brings about changes to the blood glucose levels. After a meal or drink, blood glucose rises until it reaches a peak concentration usually after 30 minutes. When the body senses the increase in blood glucose, a hormonal process involving insulin takes place to ensure that the glucose is taken up from the blood for storage and where it is needed for energy in the body. This process then brings about a decrease in the concentration of glucose until it reaches approximately the starting concentration. The original concentration of glucose is attained approximately 2 hours after eating or drinking a carbohydrate food or sugary drink respectively in healthy people. Different carbohydrates and sugary drinks have different effects on blood glucose response depending on the amount as well as the type of carbohydrate. Those that give rise to a high glucose response compared to a reference carbohydrate (usually glucose) are said to be high glycaemic index (GI) foods and those with a lower glucose response compared to a reference carbohydrate (usually glucose) are said to be low glycaemic index (GI) foods. Research has shown that diets that give rise to a high glucose response are associated with a number of abnormalities like increased risk of metabolic syndrome. Metabolic syndrome mostly comprises of insulin resistance and glucose intolerance which gives an increased risk of type 2 diabetes. It also gives rise to other conditions like high blood pressure (arterial hypertension), elevated blood insulin levels (hyper-insulinemia), elevated amounts of fat in the liver (fatty hepatosis) and elevated amounts of lipids in the blood (dyslipidemia). After type 2 diabetes become clinically apparent, the risk of cardiovascular disease also rises. Research has also shown that foods/drinks which raise blood glucose levels gradually (low GI) rather than rapidly (high GI) have health benefits which include reducing the risk of metabolic syndrome. Laboratory studies have shown that polyphenols found in fruits, vegetables and plant based foods have a positive effect on carbohydrate metabolism and can lower the blood glucose levels. This research will determine whether the presence of polyphenols in the diet has any lowering effect on the blood glucose levels and hence the glycaemic index of foods. This will be determined by asking volunteers to consume commercially available food supplements together with white bread and then determining the glycaemic response. The blood glucose response of bread will be determined initially as a control reference. All will be consumed in random order. Analysis will be done by measuring blood glucose response after consumption of the control reference meal and the test meal containing polyphenols and then determining the incremental area under the glucose curve. POMEGRANATE AND OLIVE STUDIES WILL BE TREATED SEPARATELY FOR PURPOSES OF PUBLISHING RESULTS. EACH STUDY WILL AIM TO HAVE AT LEAST 16 PARTICIPANTS.

Conditions

Hyperglycaemia

Outcome Measures

Primary Outcomes (1)

• Incremental area under the glucose curve

  6 months

Study Arms (3)

Control (no supplement)

PLACEBO COMPARATOR

Reference will be white bread to give 50 g available carbohydrates with placebo capsule

Other: Control (109 g white bread); Dietary Supplement: Dose 1; Dietary Supplement: Dose 2

Dose 1

EXPERIMENTAL

Test will comprise white bread to give 50 g available carbohydrates and one capsule of pomegranate/olive and one capsule placebo

Other: Control (109 g white bread); Dietary Supplement: Dose 1; Dietary Supplement: Dose 2

Dose 2

EXPERIMENTAL

Test will comprise white bread to give 50 g available carbohydrates and 2 capsules of pomegranate/olive.

Other: Control (109 g white bread); Dietary Supplement: Dose 1; Dietary Supplement: Dose 2

Interventions

Control (109 g white bread) OTHER

Control meal of 109 g white bread to which the response of the test meals with dietary supplements will be compared to.

Control (no supplement); Dose 1; Dose 2

Dose 1 DIETARY_SUPPLEMENT

The test meal will contain a single dose of the supplements whose response will be compared to that of the control meal.

Control (no supplement); Dose 1; Dose 2

Dose 2 DIETARY_SUPPLEMENT

The test meal will contain a double dose of the supplements whose response will be compared to that of the control meal.

Control (no supplement); Dose 1; Dose 2

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Measured
• Fasting glucose (blood glucose level before breakfast) 3.9 -5.9mmol/L
• Self-assessed
• Apparently healthy
• Not diabetic
• Not on long term prescribed medication (except contraceptives)
• Not pregnant or lactating
• Not on special diet (for losing weight or fruit extracts supplements)

You may not qualify if:

• Measured
• Fasting glucose (blood glucose level before breakfast) \>5.9mmol/L
• Self-assessed
• Not healthy
• Diabetic
• On long term prescribed medication (except contraceptives)
• Pregnant or lactating
• On special diet (for losing weight or fruit extracts supplements)

Sponsors & Collaborators

• University of Leeds: lead

Study Sites (1)

School of Food Science and Nutrition

Leeds, West Yorkshire, LS2 9JT, United Kingdom

Location

Related Publications (7)

• Jenkins DJ, Kendall CW, Augustin LS, Franceschi S, Hamidi M, Marchie A, Jenkins AL, Axelsen M. Glycemic index: overview of implications in health and disease. Am J Clin Nutr. 2002 Jul;76(1):266S-73S. doi: 10.1093/ajcn/76/1.266S.

  PMID: 12081850 BACKGROUND

• Aston LM. Glycaemic index and metabolic disease risk. Proc Nutr Soc. 2006 Feb;65(1):125-34. doi: 10.1079/pns2005485.

  PMID: 16441952 BACKGROUND

• McKeown NM, Meigs JB, Liu S, Saltzman E, Wilson PW, Jacques PF. Carbohydrate nutrition, insulin resistance, and the prevalence of the metabolic syndrome in the Framingham Offspring Cohort. Diabetes Care. 2004 Feb;27(2):538-46. doi: 10.2337/diacare.27.2.538.

  PMID: 14747241 BACKGROUND

• Grundy SM, Brewer HB Jr, Cleeman JI, Smith SC Jr, Lenfant C; American Heart Association; National Heart, Lung, and Blood Institute. Definition of metabolic syndrome: Report of the National Heart, Lung, and Blood Institute/American Heart Association conference on scientific issues related to definition. Circulation. 2004 Jan 27;109(3):433-8. doi: 10.1161/01.CIR.0000111245.75752.C6. No abstract available.

  PMID: 14744958 BACKGROUND

• Barclay AW, Petocz P, McMillan-Price J, Flood VM, Prvan T, Mitchell P, Brand-Miller JC. Glycemic index, glycemic load, and chronic disease risk--a meta-analysis of observational studies. Am J Clin Nutr. 2008 Mar;87(3):627-37. doi: 10.1093/ajcn/87.3.627.

  PMID: 18326601 BACKGROUND

• Hanhineva K, Torronen R, Bondia-Pons I, Pekkinen J, Kolehmainen M, Mykkanen H, Poutanen K. Impact of dietary polyphenols on carbohydrate metabolism. Int J Mol Sci. 2010 Mar 31;11(4):1365-402. doi: 10.3390/ijms11041365.

  PMID: 20480025 BACKGROUND

• Kerimi A, Nyambe-Silavwe H, Gauer JS, Tomas-Barberan FA, Williamson G. Pomegranate juice, but not an extract, confers a lower glycemic response on a high-glycemic index food: randomized, crossover, controlled trials in healthy subjects. Am J Clin Nutr. 2017 Dec;106(6):1384-1393. doi: 10.3945/ajcn.117.161968. Epub 2017 Oct 11.

  PMID: 29021286 DERIVED

MeSH Terms

Conditions

Hyperglycemia

Condition Hierarchy (Ancestors)

Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases

Study Officials

• Gary Williamson

  Professor and Chair of Functional foods

  STUDY CHAIR

• Hilda Nyambe

  Postgraduate research student

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: PhD student

Study Record Dates

• First Submitted: June 2, 2015
• First Posted: July 1, 2015
• Study Start: June 1, 2015
• Primary Completion: September 1, 2015
• Study Completion: December 1, 2015
• Last Updated: April 20, 2016

Record last verified: 2016-04

Locations

GB (1)