Green tea extracts in supplements could be harmful to liver and kidneys

[snagglepuss]

snip

Green tea is good for you, but only if drunk in moderation. While the polyphenols in green tea are credited with preventing heart disease and cancer, it seems they can cause liver and kidney damage if consumed in very large quantities, a review of studies into the toxicity of polyphenols has shown.

"People shouldn't be too alarmed by this, but those taking supplements may experience problems," says lead author Chung Yang of Rutgers, the State University of New Jersey.

He stresses that up to 10 small cups of green tea a day is fine. Problems are likely in people who take supplements, which can contain up to 50 times as much polyphenol as a single cup of tea.



http://www.newscientist.com/article/dn11786-green-tea-can-be-harmful-in-large-quantities.html




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Although there have been no reports of toxicity in human volunteers enrolled in intervention studies, careful monitoring of liver and kidney function is required until the risk of toxic events associated with tea catechins is established in humans.

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there have been a number of recent case reports of hepatotoxicity related to the consumption of high doses of tea-based dietary supplements (10−29 mg/kg/day po) (18). In nearly all cases (eight out of nine), patients presented with elevated serum alanine aminotransferase (ALT) and bilirubin levels. In two of nine cases, periportal and portal inflammation were observed. All cases resolved following cessation of supplement consumption. A causative role for the green tea preparations is suggested by the fact that reinjury was observed following rechallenge with the same preparations.



http://pubs.acs.org/doi/full/10.1021/tx7000515

[AsahinaKimi]

1. I love green tea but don't drink it every day..

I like to have Oolong and Pu Erh tea, and certainly by no means have more then ten cups per day.. My favorite green tea is the powdered Matcha tea, which is the kind used in the Japanese Tea Ceremony. I also have tea bags of regular green tea as well. All of my tea is Imported.. I would think Moderation with everything should be the rule of thumb.

[snagglepuss]

2. Its the tea extract found in supplements that seem to be the real concern

I drink about 10 cups of iced green tea a day but its very dilute.

[old mark]

5. Well...Moderation in...most things, anyway....nt

[laconicsax]

3. Well I sure am glad that if this is confirmed, the FDA can order the relevant supplements be pulled.

What's that? Supplements aren't regulated? The FDA can't do anything about dangerous supplements?

Well, shit.

[bananas]

4. "drunk in moderation" - great quote!

k&r for that!

[Name removed]

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