Different outcomes of the effect of green tea on weight loss (WL) and weight maintenance (WM) have been reported in studies with subjects differing in ethnicity and habitual caffeine intake. Purpose. To elucidate by meta-analysis whether green tea indeed has a function in body weight regulation.Methods. English-language studies about WL and WM after green tea supplementation were identified through PubMed and based on the references from retrieved articles. Out of the 49 studies initially identified, a total of 11 articles fitted the inclusion criteria and provided useful information for the meta-analysis. Effect sizes (mean weight change in treatment versus control group) were computed and aggregated based on a random-effects model. The influence of several moderators on the effect sizes was examined.  Results. Catechins significantly decreased body weight and significantly maintained body weight after a period of WL (^m¼_1.31 kg; Po0.001). Inhibition of this effect by high habitual caffeine intake (4300mg per day) failed to reach significance (^m¼_0.27 kg for high and ^m¼_1.60 kg for low habitual caffeine intake; P¼0.09). Also, the seemingly smaller effect of catechins in Caucasian (^m¼_0.82 kg) subjects compared with Asians (^m¼–1.51 kg; P¼0.37) did not reach significance.  Interaction of ethnicity and caffeine intake was a significant moderator (P¼0.04).  Conclusions. Catechins or an epigallocatechin gallate (EGCG)–caffeine mixture have a positive effect on WL and WM. The results suggest that habitual caffeine intake and ethnicity may be moderators, as they may influence the effect of catechins.  International Journal of Obesity (2009) 33, 956–961

“This meta-analysis or review of literature was most helpful for establishing a baseline of EGCG’s necessary for weight loss.  As you read this particular study, you’ll see that the average amount was right around 500 mg per day.  Two of the studies gave participants more than 1,000 mg of EGCG per day and found that there was no added benefit for weight loss to having more than 1,000 mg of EGCG per day.   An interesting insight from the analysis is that getting the right amount every day is more powerful than trying to over-consume in a short period of time.  The take home message here is get the right amount of EGCG’s, but do it every day.”  – Josh Smith

“Consuming beverages enhanced with green tea extract provides a protective effect against oral cancer according to this study published in November of 2009.  The ability of EGCG to kill harmul viruses and bacteria continues to be explored.  The chemoprotective effects of EGCG from a green tea extract provide substantial benefit for multiple reasons.  This study investigated the benefit of drinking green tea enhanced beverages versus taking a pill or small concentrated dose.”   – Josh Smith

Abstract Understanding the literature about the efficacy of green tea consumption in preventing and slowing the progression of cancers is critical. A systematic review of the literature was conducted using an electronic search to identify studies from 2000 to 2008 in the following database: Alt HealthWatch, CINAHL,Medline, Health Source – Consumer Edition, Health Source: Nursing/Academic Edition,Web of Science (ISI), and the Cochrane Library. Although the evidence from this review suggested associations between green tea consumption and a decreased risk for some cancers, the findings were inconclusive. In selected cases, green tea was effective in slowing the progression of the earlier stages of cancer.However, contrary evidence is reported and the dose and duration of use is variable.Most evidence stems from self-reports.Research using more rigorous designs to investigate the efficacy of green tea in humans is needed.

“This article is a recent review of 34 articles about green tea and cancer prevention that met the strict criteria to qualify to be reviewed.  Basically the strong more credible studies were reviewed.  The findings are indicating that to get the benefits and desired outcomes you need a few things.  First is the right amount of green tea every day.  Second is the caffeine content must be minimal throughought the day and that people must be consistent in their daily consumption.  Finding something that’s easy, previously measured out and convenient are important.” – Josh Smith