Effect of Polyphenol-rich Dark Chocolate on Insulin Sensitivity in Normal Weight and Overweight Adults

This study has been completed.
Sponsor:
Collaborator:
Barry Callebaut
Information provided by (Responsible Party):
Grace Farhat, Queen Margaret University
ClinicalTrials.gov Identifier:
NCT01749020
First received: December 10, 2012
Last updated: November 19, 2013
Last verified: November 2013

December 10, 2012
November 19, 2013
March 2012
July 2013   (final data collection date for primary outcome measure)
Determine if the consumption of DC rich in polyphenols can induce a change in insulin sensitivity [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
Insulin sensitivity will be determined by determined by HOMA-IR (Homeostasis Model of Assessment - Insulin Resistance)
Determine if the consumption of DC rich in polyphenols can induce a change in insulin sensitivity [ Time Frame: Baseline and 4 weeks ] [ Designated as safety issue: No ]
Insulin sensitivity will be determined by determined by HOMA-IR (Homeostasis Model of Assessment - Insulin Resistance)
Complete list of historical versions of study NCT01749020 on ClinicalTrials.gov Archive Site
  • Determine if the consumption of DC rich in polyphenols can induce a change in glucose levels [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in Lipid profile (TC, HDL, LDL & TG) [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in oxidized LDL levels [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in BMI and Waist circumference [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in blood pressure [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in salivary cortisol-to-cortisone ratio [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in high sensitivity CRP [ Time Frame: Baseline and Week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in glucose levels [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in Lipid profile (TC, HDL, LDL & TG) [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in oxidized LDL levels [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in BMI and Waist circumference [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in blood pressure [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
  • Determine if the consumption of DC rich in polyphenols can induce a change in salivary cortisol-to-cortisone ratio [ Time Frame: Baseline and week 4 ] [ Designated as safety issue: No ]
Not Provided
Not Provided
 
Effect of Polyphenol-rich Dark Chocolate on Insulin Sensitivity in Normal Weight and Overweight Adults
Effect of Polyphenol-rich Dark Chocolate on Insulin Sensitivity in Normal Weight and Overweight Adults

The purpose of the study is to determine the effect of polyphenol-rich dark chocolate on insulin sensitivity in normal weight and overweight adults.

Polyphenols may have several favourable effects on health. Dark chocolate (DC) is one of the highest sources of polyphenols in foods. The aim of the study is to determine the effect of polyphenol-rich dark chocolate on insulin sensitivity in normal weight and overweight adults. Seventy four volunteers with no history of hypertension, cardiovascular diseases or diabetes will be recruited. Participants will randomly receive 20g daily of one of the two different types of DC: Placebo DC (low in polyphenols) or DC rich in polyphenols (500mg) for a period of four weeks. Participants will be asked to make two appointments to the university clinical lab. Anthropometric measurements (height, weight, waist circumference), blood and saliva samples will be taken during each of the 2 visits. Compliance will be tested by the measure of total polyphenols in a 24-hour urine sample in some random samples before and at the end of the intervention. To monitor any fluctuations in the participants' diet or physical activity during the study period, a three-day diet diary and a physical activity questionnaire will be collected before the start of the study and after four weeks. Data will be analysed with an ANCOVA with time (pre- and post-) and treatment (DC and placebo) as between-subject factor.

Interventional
Not Provided
Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind (Subject)
Primary Purpose: Basic Science
Insulin Resistance
  • Other: Polyphenol-rich Dark chocolate
    Participants will be asked to consume 20g of dark chocolate containing 500mg of polyphenols daily for a period of 4 weeks
  • Other: Placebo Dark chocolate
    Participants will be asked to consume 20g of dark chocolate containing little or no polyphenols for a period of 4 weeks
  • Experimental: Polyphenol-rich Dark chocolate
    Dark chocolate with 500 mg of polyphenols
    Intervention: Other: Polyphenol-rich Dark chocolate
  • Placebo Comparator: Placebo Dark chocolate
    This chocolate contains little or no polyphenols
    Intervention: Other: Placebo Dark chocolate
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Completed
61
July 2013
July 2013   (final data collection date for primary outcome measure)

Inclusion Criteria:

  • Adults with no history of hypertension, diabetes and cardiovascular diseases
  • BMI from 18-24.9 and BMI >25
  • Males and Females
  • Age: 18-65 years

Exclusion Criteria:

  • Participants with cardiovascular diseases, hypertension or diabetes
  • Smokers and heavy alcohol drinkers
  • Participants taking any medications that affect insulin, cholesterol, triglycerides or blood pressure
  • Participants taking dietary supplements containing high doses of antioxidants
  • Postmenopausal women taking HRT (Hormone Replacement Therapy)
  • Participants who recently participated or are currently on a weight management program
  • Participants with regular consumption of cocoa or DC (> 1 serving/week)
Both
18 Years to 65 Years
Yes
Contact information is only displayed when the study is recruiting subjects
United Kingdom
 
NCT01749020
DC-Ins01
No
Grace Farhat, Queen Margaret University
Queen Margaret University
Barry Callebaut
Study Director: Emad Al-Dujaili, PhD Queen Margaret University
Queen Margaret University
November 2013

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP