Polyphenols are bad in large quantities
 

http://www.newscientist.com/article/...uantities.html
/ well, from an article in Chemical Research in Toxicology, vol 20, p
583 ... if anyone has access to that

not very surprising since anything in large quantities is bad

"Problems are likely in people who take supplements, which can contain
up to 50 times as much polyphenol as a single cup of tea." ... "liver
toxicity" in humans... dont know what the actual findings were -
probably just by liver enzyme blood tests, not by biopsy to see if any
real damage happened.

But they did manage to kill a couple lab animals with large doses of
polyphenols, i guess from liver failure.

Polyphenols are bad in large quantities
 

Chemical Research in Toxicology, vol20
Possible Controversy over Dietary Polyphenols: Benefits vs Risks
http://pubs.acs.org/cgi-bin/sample.c...tx7000515.html