Epigallocatechin gallate (EGCG), also known as epigallocatechin-3-gallate, is the ester of epigallocatechin and Gallic acid and is a type of catechin. EGCG – the most abundant catechin in tea – is a polyphenol under basic research for its potential to affect human health and disease. EGCG is used in many dietary supplements. When taken orally, EGCG has poor absorption even at daily intake equivalent to 8–16 cups of green tea, an amount causing adverse effects such as nausea or heartburn. After consumption, EGCG blood levels peak within 1.7 hours. The absorbed plasma half-life is ~5 hours, but with the majority of unchanged EGCG excreted into the urine over 0 to 8 hours. Methylated metabolites appear to have longer half-lives and occur at 8-25 times the plasma levels of unmetabolized EGCG.
Scientific Tracks Abstracts: Journal of Chromatography & Separation Techniques