Green tea extract for fat metabolism Original paper

In this randomized controlled trial, green tea extract improved some measures of fat metabolism in postmenopausal women with overweight or obesity.

The effect of green tea extract (GTE) on fat metabolism.

The primary outcomes included respiratory quotient (RQ; a reflection of carbohydrate and fat oxidation), carbohydrate oxidation, fat oxidation, and resting energy expenditure (REE; the number of kilocalories burned at rest).

The secondary outcomes were dual-energy X-ray absorptiometry markers (fat-free mass, fat mass, and visceral adipose tissue), Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), and levels of fasting glucose, insulin, total cholesterol, HDL-C, LDL-C, triglycerides, adiponectin, C-reactive protein (CRP), alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, creatinine, leptin, adrenaline, and noradrenaline.

28 postmenopausal women (average age of 59) with overweight or mild obesity (defined as a BMI of 30–35).

The participants in the study took 150 mg of Greenselect Phytosome (standardized to contain at least 13.0% epigallocatechin-3-gallate and not more than 0.1% caffeine) or a placebo twice daily for 60 days.

Between groups, GTE decreased RQ to a very small degree (−0.04) but increased fat oxidation (+11.04%) and decreased carbohydrate oxidation (–11.04%) to a large degree. GTE also increased REE and decreased insulin, HOMA-IR, waist circumference, and CRP compared with placebo.