Green tea extract and catechol‐O‐methyltransferase genotype modify the post‐prandial serum insulin response in a randomised trial of overweight and obese post‐menopausal women

Document Type


Department or Administrative Unit

Nutrition Exercise and Health Sciences

Publication Date




Green tea extract (GTE) may be involved in a favourable post‐prandial response to high‐carbohydrate meals. The catechol‐O‐methyltransferase (COMT) genotype may modify these effects. We examined the acute effects of GTE supplementation on the post‐prandial response to a high‐carbohydrate meal by assessing appetite‐associated hormones and glucose homeostasis marker concentrations in women who consumed 843 mg of (−)‐epigallocatechin‐3‐gallate (EGCG) or placebo capsules for 11–12 months.


Sixty Caucasian post‐menopausal women (body mass index ≥ 25.0 kg m–2) were included in a randomised, double‐blind feeding study. GTE was consumed with a breakfast meal [2784.0 kJ (665.4 kcal); 67.2% carbohydrate]. Blood samples were drawn pre‐meal, post‐meal, and every 30 min for 4 h. Participants completed six satiety questionnaires.


Plasma leptin, ghrelin and adiponectin did not differ between GTE and placebo at any time point; COMT genotype did not modify these results. Participants randomised to GTE with the high‐activity form of COMT (GTE‐high COMT) had higher insulin concentrations at time 0, 0.5 and 1.0 h post‐meal compared to all COMT groups randomised to placebo. Insulin remained higher in the GTE‐high COMT group at 1.5, 2.0 and 2.5 h compared to Placebo‐low COMT (P < 0.02). GTE‐high COMT had higher insulin concentrations at times 0, 0.5, 1.0, 1.5 and 2.0 h compared to the GTE‐low COMT (P 0.04). Area under the curve measurements of satiety did not differ between GTE and placebo.


GTE supplementation and COMT genotype did not alter acute post‐prandial responses of leptin, ghrelin, adiponectin or satiety, although it may be involved in post‐meal insulinaemic response of overweight and obese post‐menopausal women.


This article was originally published in Journal of Human Nutrition and Dietetics. The full-text article from the publisher can be found here.

Due to copyright restrictions, this article is not available for free download from ScholarWorks @ CWU.


Journal of Human Nutrition and Dietetics


© 2016 The British Dietetic Association Ltd.