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I was thinking the same thing. Perhaps the trade-off made by evolution is about saving energy?

In that case it shouldn't be a problem to boost the innate immune system, as long as you have surplus calories to spend. But it could be something else entirely.

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It could be just "good enough" as it is. That is, as another poster commented, there is a Th1 or a Th2 reaction. And these in a sense compete. Only one appears to be active.

The current framework of our immune system could go back quite some time. Even to our mammalian cold-blooded ancestors, 200? mya. When I think of cold blooded, I think of creatures able to remain static and at rest for a long time, periods of low-energy usage. So maybe this framework comes from before warm blooded mammals?

And, if it works well enough that people can breed (which used to be 15 years to 30 years old), and if dying after, oh well. Why evolve better? Or maybe too much monkeying has downsides.

Look at sickle cell anemia. Quite beneficial with malaria parasites around, not so much without them.

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Such as autoimmune disorders or other hyperinflammatory disorders?

Graves’ disease, lupus/SLE, psoriasis, type 1 diabetes, myasthenia gravis, Addison’s disease, Hashimoto, Goodpasture, etc.

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> cranking up the innate immune system all the time reduced illness with no downsides

But isn't that what the adjuants that are currently in nearly every vaccine do anyway. That is forcing the triggering of immune response when there wouldn't be none or very little response naturally?

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That’s adaptive rather than innate, as the article makes clear.
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Evolution just needs people survive long enough to reproduce. If they get sick afterwards, it doesn't care.
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Evolution happens both sides - you and the virus/bacteria trying to live off you.

One of the risks of an always on response, is if something evolves to evade it - you have nowhere to go.

It's why taking an antibiotic at breakfast everyday is not a good idea.

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Unless they are contributing to the survival of their offspring.
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It can work the other way, too. Your offspring may be more likely to survive if you stop consuming resources once they become viable.
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Are you sure that availability of resources was a limiting factor during a large part of human evolution?

ie what has driven human population growth - a fundamental change in availability of natural resources or a fundamental change in how humans exploited them?

I'd argue it's the latter, and that's driven by accumulated knowledge - and before writing - the key repository of that was - old people.

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The vast majority of human evolution happened in non-humans
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Humans have selective adaptations to reduce resource competition between older and younger members of populations - examples are menopause and testosterone levels.

Part of the reason it benefited us that some but not all people become old is because people require more attention during two phases of their lives. Our biological evolution has prioritized care for the very young over the very old, with respect to a limit on resources (like attention), effectively until the modern age. In some cultures, for instance, those with teeth must pre-chew food for those without, or expected members to engage in ritual suicide at a certain age.

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Except humans are a social species and the bands of humans who survived were the ones with the behaviors which kept elders around because of their benefits to our capacity for social learning.
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It’s only an imperfect vaccine — broad immune protection. Evolution probably has come up with a bunch of these.
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Evolution is not a perfect optimizer.
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It's probably because maintaining the immune system at high levels costs more energy.

You probably know that antibiotic use is rampant in industrial livestock. But do you know precisely why?

Antibiotics aren't just given prophylactically to prevent infections; constant low doses actually *increase the animal's size*. The animals can put more energy into growing larger, and spend less on their immune system.

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