Re-analyzing the data from the ITP

I was reading about how using EGCG present in tea extends the median lifespan of rats +13% by protecting their liver and kidneys.

When I remembered this contradicts what have been found in the ITP using Green Tea Extract. So diggning a little bit deeper I run into this study:

The Gehan test identifies life-extending compounds overlooked by the log-rank test in the NIA Interventions Testing Program: Metformin, Enalapril, caffeic acid phenethyl ester, green tea extract, and 17-dimethylaminoethylamino-17-demethoxygeldanamycin hydrochloride

It looks like there are plenty of compunds that can be an advantage early on and they may bring some disadvantage later in life. Too much green tea seems to be one of those.

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From the paper:

“Three drugs that had been identified to extend lifespan using the log-rank test no longer had statistically significant effects according to the Gehan test: acarbose in females at 400 ppm and 1000 ppm (Fig. S2A and S2B), butanediol in females (Fig. S2C), and glycine in males (Fig. S2D)”

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So much conflicting information all the time

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If I understand correctly, this only means that the life extension is happening mostly at the end of the data. So this test is not picking it up.

Speaking of green tea: new New Atlas piece:

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I might be misunderstanding you, but think the paper argues/shows that some ITP compounds look strongest in early–mid life and wane later (either less effective later or negative effects increase later).

This could justify time-limited use in principle?

Btw, this is the case for some things elsewhere - eg aspirin might be good for a 30-50 year old to take for a decade or two to lower some key cancer rates, but later in life the negatives might dominate

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Here’s something interesting:

https://www.sciencedirect.com/science/article/pii/S2352364621000171

Content of methylated EGCg in Benifuuki leaves varies markedly.

Home-brewed Benifuuki green tea infusions contain relevant amounts of methylated EGCg only in a few cases.

But at least it sometimes has methylated-EGCG.

And why would we care about methylated-EGCG?? Because it has a half-life in the body of 24 hours, according to a Google search, whereas regular EGCG has only a half-life of 5 hours.

Maybe you get more of the anti-aging effect of EGCG if you can boost the half-life by nearly 5x like that.

Addendum: And here is what Google says about methylated EGCG:

Methylated EGCG is a derivative of EGCG (epigallocatechin-3-gallate), a potent antioxidant in green tea, where one or more methyl groups (CH3) are attached to its phenolic hydroxyl groups. This modification makes it more stable, more soluble in lipids, and improves its absorption and biological activity in the body. Methylated EGCG is found naturally in some tea cultivars like ‘Benifuuki’ and is associated with stronger anti-allergic effects compared to EGCG.

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