Worrying whether taurine or whatever substance “X” revs up mTOR, whilst rapamycin turns it down is classic mechanistic reasoning, no? I’m a very simple guy, so I like the black box approach. You have inputs into the black box, something happens inside the black box, and then you have outputs at the other end. Taurine, substance “X”, rapamycin etc. are the inputs. By definition in this scenario, we don’t know what happens inside the black box. We can only observe the output - here, outcome studies measuring whatever the marker, perhaps all cause mortality, some morbididy outcome etc.
Now, if I find that input of taurine into the black box results in an output that has as an outcome longer lifespan/healthspan, I’m satisfied. Now that’s mice - ignorable. But we have human studies that show various good outcomes - lowers BP, helps in heart health (albeit in heart failure), exercise and various other measures. So the positives are there, even if the most dramatic (lifespan) are not provable in humans. OK, what about the negatives - I’ve looked for them, not found them. I looked for interactions with drugs/supplements I take - nothing. So, being the simple guy that I am, I go ahead and take taurine, although only in doses that have shown some clinical effect 2-4g a day (1.6g/day was shown to lower BP, which is slightly elevated for me). It seems studies show that up to 6mg/day is safe.
Now, asking about taurine countering rapa, is asking about what happens inside the black box. By definition we don’t know - because we don’t have a perfect model of how the human body works, we can only speculate. I am happy to speculate just as lustily as the next guy, and read with pleasure the various papers on pubmed, but at the end of the day, it’s speculation. Outcomes trump it every time.
Yet, since we all have to make decisions, we need some kind of reasoning chain. Yours may be better than mine. Here’s mine:
1)There is no evidence that rapa works better in old mice, vs supplied all through life from young to old. In fact, we have experiements that the longer on rapa, the longer mice live. Including starting at a young age.
2)Taurine declines in mice with age. But it is higher in youth - yet rapa works in young mice, so it doesn’t seem that higher-taurine-young-mice don’t benefit from rapa. This suggest strongly to me, that if I have youthful levels of taurine thanks to supplementation, it will not prevent rapa from being beneficial - after all, if I started rapa at 20 with a high level of taurine, I’d still benefit from rapa, just as young mice do.
Of course, if rapa doesn’t benefit humans, then that’s a rapa problem and has nothing to do with taurine, so we can ignore that - it’s in the very assumption itself. We assume/hope/take a risk, that rapa works for us. I don’t see how taurine enters into it.
Now, one may ask “won’t it interfere with rapa, because mTOR” - you’re asking about what happens inside the black box - but I say, the outcome in young mice with high taurine is beneficial, so…
As long as we’re speculating, I can speculate as much as the next guy/gal. I speculate that rapa simply turns down the mTOR, so taurine is irrelevant in that case. It’s as if you rev up the engine with taurine which ordinarily will make you race down the street - but rapa puts the transmission in neutral - you can rev as much as you wish it won’t make any difference.
However, we are pulsing rapa. And we have seen in the PEARL trial, and anecdotal evidence (plus waiting on Brad Stanfields study), that muscles benefit on rapa - stronger. Here we see a perfect analogy.
Somone worries, but since muscles grow with mTOR activation, won’t rapa shrink your muscles? Mechanistic speculation about what happens inside the black box. Then we look at outcomes - the opposite seems to be true, muscles benefit from rapa. Lesson learned? Only outcomes matter. Worrying about the inside of the black box is of intellectual curiosity (which I share with gusto!), but for actionable pointers, I look to outcomes and try not to be guided by mechanistic speculation.
It’s all a gamble. It’s possible the opposite is true - rapa may inhibit whatever the benefits of taurine are, rather than taurine abolishing taurine benefits. I’m gambling that they’ll be additive. What’s the truth - we won’t know for now, or maybe ever. Speculatively, I turn again to mouse studies. High taurine in young mice is presumably good, and rapa in young mice is also good, so it doesn’t seem as if rapa demolishes the benefits of taurine. It looks like regardless of high (young mice) taurine status or low (old mice) taurine status, rapa is beneficial. It seems that if rapa doesn’t affect taurine, and taurine rapa, then perhaps one could stack the benefts of both. Same way exercise is good for muscles, and it looks like rapa is good for muscles so one does not abolish the other, as muscles benefit from both. It’s not “exercise alone = muscle benefits” and “rapa alone = muscle benefits” - it’s “exercise AND rapa = muscle benefits” That’s my roll of the dice with taurine - they’ll stack positively.
Now, since we pulse rapamycin, my plan is (I start rapa in January), to not supplement with taurine on the day of rapa and the following day, since anecdotal evidence with exercise seems to be that more folks report better resuts with not exercising on those two days. Of course, my reasoning might be all wrong, but being a simple man I must rely on my own meager resources, and I admire those who can figure it out better. YMMV.
