"[Y]ou can think about all these processes as competing for calories over the course of the day. And normally, low priority things like having a really high inflammation response or having a high stress response, those get tamped down in a highly active population like we've all evolved in. But now, you move to these weird zoos that we've built ourselves, where you don't have to be active, food's available all over the place, energy supply is really easy. And now, these low priority activities which used to probably only happen very occasionally in the past, in the deep past, now are happening all the time, chronically, at these super high levels, and it's actually really bad for you."
That's a good read. But one of the processes competing for calories is the immune system.
> If you take somebody who is really sedentary and you get them exercising, what happens? Things like inflammation, which is your immune system being overactive, goes down. [Also cortisol level when under stress, and reproductive hormone levels, go down.]
So that puts a small hole in the "exercise helps the immune system clear up cancer" theory. Maybe it in fact stops the immune system causing cancer. Or maybe it does both things, since biology is messy and the immune system might have multiple energy budgets for all I know.
https://www.msnbc.com/msnbc-podcast/examining-energy-evoluti...
"[Y]ou can think about all these processes as competing for calories over the course of the day. And normally, low priority things like having a really high inflammation response or having a high stress response, those get tamped down in a highly active population like we've all evolved in. But now, you move to these weird zoos that we've built ourselves, where you don't have to be active, food's available all over the place, energy supply is really easy. And now, these low priority activities which used to probably only happen very occasionally in the past, in the deep past, now are happening all the time, chronically, at these super high levels, and it's actually really bad for you."