[TameAntelope]

So then it wouldn't "work", where "work" as used here is defined, "to function or operate according to plan or design".

And no, it's not reasonable to assume I meant "work" as in, "have an anti-aging serum that has strong negative side effects."

[q-big]

An anti-aging serum works if it reduces or removed specific (or even most/all?) effects that are related to aging.

[bluGill]

Relative to other side effects. Remember we are in a post serum existing scenario so we would have the knowledge of those as part of the discussion on if it works.