Catechins - benefits of green tea
Catechins are well known as antioxidants and used traditionally to prevent several diseases.
The name comes from catechu family and more specifically from Mimosa catechu  Catechins can be found in cacao , green tea and grapevines, among other plants. Since its discovery around 3000 B.C in China, green tea has been a popular beverage consumed worldwide. Green tea (Camellia sinensis) contains various ingredients with beneficial health effects, the main ones being catechins.
Catechins are secondary metabolites produced by this kind of plants. They are chemically classified as flavonoids and comprise different isomers: catechin, catechin gallate (Cg), gallocatechin, gallocatechin gallate (GCg), epicatechin, epicatechin gallate (ECg), epigallocatechin, and epigallocatechin gallate (EGCg). Epigallocatechin gallate (EGCG) is the compound with the higher bioactivity.
These compounds show protective effects against diseases such as cancer, obesity, diabetes, arteriosclerosis, neurodegenerative diseases, and tooth decay. They also have antibacterial, antiviral, and hepatoprotective effects. Tea catechins are strong antioxidants and bind to proteins, lipids, nucleic acids, and metals. They also bind to the 67 kDa laminin receptor,8 B-cell lymphoma 2 (Bcl-2) proteins, vimentin, and peptidyl prolyl cis/trans isomerase, which are targets of EGCD and can be used in anticancer therapy. 
As any other phytotherapeutic compound, aside from their health benefits, a misuse of traditional herbal medicine can lead to severe adverse events. Exolise is an 80% ethanolic dry extract of green tea that has been available in France, Belgium, Spain and the United Kingdom since 1999, used in weight loss. A study reported a case of fulminant hepatitis during self-medication with Exolise, which ended in liver transplantation . The European Food Safety Authority recommended a daily intake of maximum 800 to prevent risk of liver damage .
- “Catechin,” Wikipedia. 21-Feb-2019.
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ESR1 Inés Rodríguez Leal