T Nation

Green Tea and Glucuronidation


I was looking into green tea a bit, it was interesting as it appears some rat studies are not valid it oral ingestion since rats have an incredibly high rate of glucuronidation relative to humans (food for thought).

It appears that although a lesser concern, glucuronidation still happens in humans with EGCG and the other catechin ECG.

Has anyone had luck with brewing green tea leaves with whole black peppers in regards to fat burning or thermogenesis? It would make sense to me since piperine is water soluble that it can be extracted from whole black peppers and thus increase the bioavailability of brewed EGCG (building on that, anybody know the amount of piperine in black pepper?)

I also recently started brewing my green tea with chili pepper flakes for the capsaicin, highly recommended for the nice kick it gives.


I just stick with green tea and lemon.


Yeah lemon. Piperine gives me issues, but it's pretty weak in pepper though. You'd get more esential oils than pure piperine I believe.


I was just looking into it a bit, and it appears that D-limonene enhances UDP-glucuronosyltransferase enzyme activity. That's the opposite of what I am looking for though, since EGCG is falsely tagged by this enzyme family.


Also, correction in my first post, piperine seems to only be slightly water soluble but more fat soluble. So that sucks with EGCG's inhibition of lipase :frowning:


Sure, maybe it does, but... remember that popular study froma couple years ago that showed lemon juice increases EGCG uptake (due to the acidic envronment I believe). Citric acid would probably be just as good if you're concerned with limonene interfering. Limonene has certain merits on it's own though...


Three Musketeers in this thread.


Know of any in vivo studies?

I found one (linked) that showed digestion of common tea formulations, or which vitamin C, citric acid, and juices were analyzed. It did come to the conclusions that juice, vitamin C, and dairy all increase catechin uptake (with juice being better than straight vitamin C, milk being worst but still twice as good as normal).

However, looking at the full text the methods were essentially putting the solutions into diluted aliquots and treating them with different acid, base, and enzyme treatments similar to gastric and intestinal uptake. They never touched down on the hepatic environment.

Although the instability of EGCG in the stomach/intestine is new to me, guess I'm going to start lacing it with lemon or lime now.

I lol'd


Also, just to add (for the hell of it), that last study found that the chelating agent EDTA increased EGCG stability more-so than vitamin C did in the pH changes.

Might be worth noting if EDTA binds with tannins and prevents their intestinal malaise. Could be a nice one-two punch.


I don't think dairy works well with Green tea: