Green Tea Dietary Supplements Differ Chemically From Tea
Beverage tea holds advantages over green-tea supplements according to an analyis by USDA financed researchers.
The analysis, published in the March Journal of the Association of Analytical Communities International (AOAC), indicates commercially available green-tea based dietary supplements are not the same as green tea. The AOAC is an organization of scientists dedicated to excellence in analytical methods. The association's peer review journal is published six times a year.
The article noted that samples from eight liquid dietary supplements and 12 green tea pills (capsules and tablets) showed evidence of higher degradation of the catechins and flavonol glycosides that are found in tea leaves.
Researcher Dr. Pei Chen, a research chemist with the USDA's Agricultural Research Service (ARS) writes that “Although there are some good green tea dietary supplement products, there is no way for the consumer to know the qualities of the green tea dietary supplement products from reading the labels." Some of the products contained unlabeled ingredients including sucrose and fenugeek.
Dr. Chen concluded that “the claim that a green tea dietary supplement is a good alternative for tea leaves is questionable from a chemical composition point of view."
Source: Journal of AOAC International: A Non-targeted Approach to Chemical Discrimination Between Green Tea Dietary Supplements and Green Tea Leaves by HPLC/MS