Does high dose green tea extract help with weight loss – results of a clinical trial

A variety of weight loss products are formulated with green tea and marketed for the purpose of losing weight.

Even some clinical trials have suggested a benefit in cardiovascular markers, however, the results in terms of weight loss are mixed.

Research recently published in Clinical Nutrition tested high dose green tea extract for promoting weight reduction in a double blind placebo controlled clinical trial.

The results of this study along with the results of other studies is beginning to shed light on the use of green tea for weight loss.

Here are the details of the study:

  • Subjects received Green Tea Extract or Placebo for 12 weeks
  • Patients consuming green tea catechins from food and beverages other than the supplement during the study was prohibited
  • Human subjects consuming more than 200 mg of caffeine werre excluded from the study.
  • 77 subjects completed the study

Here is what was in the daily Green Tea Extract: 

Component % in weight Daily dose (in mg)
EGCG (Epigallocatechin gallate) 57.12 856.8
ECG (Epicatechin gallate) 15.74 236.1
EGC (Epigallocatechin) 7.7 115.5
EC (Epicatechin) 4.8 71.9
GCG (Gallocatechin gallate) 4.25 63.7
GC (Gallocatechin) <0.07 <1.05
Caffeine <0.07 <1.05
Cellulose 10.3 155

Here is a summary of the results: 

  • Green Tea Extract reduced Body weight by 2.4 lbs
  • Green Tea extract reduced waist circumference by 0.9 inches
  • Total cholesterol reduced by 15 mg/dL
  • LDL dropped 12 mg/dL
  • Adiponectin was increased which is involved in blood sugar regulation and fat breakdown
  • No adverse events were reported

Here are the results before and after Green Tea extract

Before Green Tea Extract After Green Tea Extract P-value
Weight, kg 76.8 (11.3) 75.7 (11.5) 0.025
Body mass index, kg/m2 31.0 (3.8) 30.6 (3.9) 0.018
Waist circumference, cm 95.1 (9.6) 92.8 (9.8) 0.023
Alanine transaminase (IU/L) 27.2 (14.9) 33.6 (22.2) 0.041
Total cholesterol, mg/dL 198.8 (35.9) 183.9 (34.2) 0.005
Low density lipoprotein, mg/dL 124.7 (30.5) 112.1 (27.0) 0.006
Adiponectin (mg/ml) 20.9 (11.0) 24.0.0 (10.7) 0.009

What dose of green tea is needed for weight loss?

On the other hand, in our previous study [15 we found that daily consumption of green tea extract containing 491 mg of catechins (302 mg EGCG) did not produce weight reduction in obese women, although significantly decreased plasma cholesterol and triglycerides were observed.

Take away message: High dose Green Tea extract can reduce body weight in women with central abdominal obesity.  Reductions in total cholesterol and LDL (often called the ‘bad’ cholesterol) was reduced.  Interestingly a slight increase in the liver enzyme alanine transaminase, however it remained in the normal range.  The results of this study suggest Green Tea extract can help with reducing weight loss.  One possible mechanism appears to be by increasing adiponectin which is involved in regulating blood sugar and breaking down fat.  It is important to remember green tea extract should be considered one part of health lifestyle choice – don’t forget to exercise and make good meal choices.

Clinical Nutrition. 2016 June; Volume 35 (Issue 3): Pages 592-9.

Jeremy Johnson, PharmD, PhD


Categories: Antioxidant, Body weight, Cholesterol, Plant Extracts, Plant Medicine, Weight loss