According to researchers in Japan there is a substance in green tea that blocks a key cell receptor that helps produce an allergic response. It is called methyleatedepigallocatechingallate(EGCG). It seems to work by works by blocking the production of histamine and immunoglobulin E (IgE). These are two compounds in the body that help create and sustain allergic reactions. In this study, a methylated form of EGCG blocked histamine receptors on human basophils (white blood cells that release histamine).
In past studies, other compounds found in green tea have been shown to be anti-allergenic. The study appeared in the Oct. 9, 2002 issue of the Journal of Agricultural and Food Chemistry, a peer-reviewed publication of the American Chemical Society.
Hirofumi Tachibana, the study’s chief investigator and an associate professor of chemistry at KyushuUniversity in Fukuoka, Japan notes that green tea is “a promising source of anti-allergenic agents” and believes that people with allergies should consider drinking it. It should be noted, however, that no therapeutic dose has been established for green tea and these results are preliminary.