mTOR. Higher protein intake upregulates our nutrient-sensing system mTOR, signalling there must be plenty of nutrients around so grow rapidly, reproduce and (as I understand it) sort of burn out quickly and drop dead? Not sure that's exactly the best way to describe it, but something like that. So then low protein downregulates mTOR. Hey, maybe there's a famine or something, thinks our body, so better hunker down and go into repair mode and preserve one's self to survive long-term in case things get better so we can then eat plenty and reproduce (and then drop dead?). So some low-protein advocates think we're better off not to be upregulating mTOR with lots of protein because not only we but things like cancer cells and stuff like to grow, so that we should keep it tamped down with low protein so we'll keep repairing ourselves, stay healthy and live a long time. Except then isn't there the potential problem of sarcopenia, muscle wasting, getting weaker and more frail as we age if we don't upregulate mTOR to do some muscle growth to prevent all that? On the one hand people like Dr. Rosedale and Dr. Gundry suggest fairly low protein targets to downregulate mTOR and stay healthy; on the other I heard a talk by another doctor say women of a certain age should be eating lots of protein several times each day to upregulate mTOR or the muscle wasting will occur. So kind of seem like opposites--do we want mTOR upregulated, downregulated or what as we age? Anyone who knows more about this have any thoughts? It seems to me like more than a trivial matter because who wants to be maybe really long-lived but weak and frail? There's got to be more to this.