Friday Jan 30, 2015 (foodconsumer.org) -- Green tea extract may be used as a dietary supplement to treat obesity or help weight loss, according to a new study conducted by scientists at Korea Food Research Institute in South Korea.

Green tea extract or its main ingredient epigallocatechin gallate (EGCG) has been known for its anti-obesity or antiobesogenic affect in addition to their anticancer bioactivity.  The current study provides new evidence to confirm findings from previous studies suggesting that green tea extract may help fight obesity.

In the study, mice were fed either a normal diet or a high fat diet or a high fat diet supplemented with 1% green tea or high fat diet with crude catechins and serum and liver metabolites were analyzed using LC-MS and compared.

As a result, mice fed high fat diet with 1% green tea had reduced adipose tissue and lowered serum concentrations of triglycerides or blood fat, glucose or blood sugar, insulin, and leptin, compared to mice fed the high fat diet alone.

High fat diet has been known to induce obesity and chronic low grade inflammation.  The current study also found high fat diet induced abnormal mitochondrial lipid beta-oxidation, which were normalized by caffeine- and theanine-enriched great tea.

The study concluded that high fat diet results in abnormal lipid and energy metabolism and green tea can alleviate the dysfunction of the lipid and energy metabolism and green tea renders an anti-obesity effect.

It is almost certain that green tea, green tea extract or EGCG can help fight obesity.  However, the dose must be high enough to have the efficacy.  The problem is, at such doses, these anti-obesogenic agents could induce severe hepatotoxicity.

Green tea extract or EGCG has also been tested for their anticancer effect.  Again, severe adverse effects associated with high doses of green tea extract or EGCG make it impossible for these anticancer agents to be used clinically. (David Liu, Ph.D.)

Lee LS, Choi JH, Sung MJ, Hur JY, Hur HJ, Park JD, Kim YC, Gu EJ, Min B, Kim HJ.  Green tea changes serum and liver metabolomic profiles in mice with high-fat diet-induced obesity.  Mol Nutr Food Res. 2015 Jan 28.