Format

Send to

Choose Destination
Food Funct. 2012 Oct;3(10):1035-43. Epub 2012 Jul 16.

Differential effect of polyphenol-rich dark chocolate on biomarkers of glucose metabolism and cardiovascular risk factors in healthy, overweight and obese subjects: a randomized clinical trial.

Author information

1
MRC Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, UK. suzana.almoosawi@mrc-hnr.cam.ac.uk

Abstract

The association between excess cortisol and various parameters of metabolic syndrome including hypertension, insulin resistance and dyslipidaemia is increasingly recognised. The present single-blind randomised placebo-controlled cross-over study compared the effect of polyphenol-rich dark chocolate (DC) on biomarkers of glucose metabolism, lipid profile, and blood pressure (BP) in females with BMI ≥ 25 kg m(-2) (n = 21) and females with BMI < 25 kg m(-2) (n = 21). Volunteers consumed 20 g of DC containing 500 mg polyphenols or a placebo DC with negligible polyphenol-content daily for 4 weeks, separated by a 2-week washout period. Systolic BP and diastolic BP decreased after 4 weeks of polyphenol-rich DC. Placebo raised fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR) and salivary cortisol, an effect that was significantly different from polyphenol-rich DC which had a negligible effect on fasting insulin, HOMA-IR and salivary cortisol. Females with BMI ≥ 25 kg m(-2) responded less favourably to placebo than lean females and consequently had higher fasting insulin and HOMA-IR, in addition to a lower quantitative sensitivity check index (QUICKI) after ingestion of placebo compared to polyphenol-rich DC. No significant changes in lipid profile were observed. This study provides evidence for the metabolic benefits of consuming polyphenol-rich dark chocolate while demonstrating the possibility of adverse effects occurring with polyphenol-poor chocolate placebo.

PMID:
22796902
DOI:
10.1039/c2fo30060e
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Royal Society of Chemistry
Loading ...
Support Center