The nervous system may be protected by polyphenols found in green tea. Research published in the journal Biological Psychiatry (Vol. 62, Issue 12; Dec. 15, 2007), rats given a toxic substance (6-OHDA) were protected by substances found in green tea. There are antioxidant substances (chemicals called polyphenols) found in green tea. Four such substances are epigallocatechin gallate (EGCG), Epicatechin (EC), epicatechin gallate (ECG), and epigallocatechin (EGC). In the study, rats were divided into six groups. Four groups were given 6-ODHA and a combination of the polyphenols found in green tea, in varying doses. One group was given the green tea polyphenols only and another group, used as a control, received neither substance. The polyphenols acted to protect neurons from the damage caused by 6-OHDA. The highest dose of polyphenols had the greatest protective effect, with 3.7 times as many neurons surviving in that group, compared to controls.
Of course this does not establish that drinking green tea protects humans from Parkinson’s disease. Human studies need to occur to prove this connection. It does show that the antioxidants in green tea may act to protect nerve tissue.