Medical mistreatment for half foot’s.
I wonder if half foots live shorter because of a factor that they don’t really have much mana to do magic? Of course, I think the manga shows it pretty clearly that half foots face horrid prejudice and racism, significantly more so than most of the other humans (I’d say the most actually if we’re not counting Demi-humans). With all of that in mind, that would mean they probably experience medical racism, and considering they’re not a race that can really study healing magic (probably one of the worlds best medical treatments) nor would they so easily have friends/ family specialised in this, they immediately lack as much access to healthcare as most others would.
Dwarves I believe also have low mana, but they have a close relationship to gnomes who definitely do not, as well as dwarves are (again) not the main targets to systemic racism, unlike half foots, so medical treatment naturally comes easier.
Of course, I think their lifespan is a result of many many things. Like their body size, their time period… etc. But lack of accessibility to medical treatment isn’t something I’ve seen discussed enough! Unless I’m not looking enough idk.
This would be more of a headcanon but I imagine if tall men and half foot were treated fully equally systemically then they could probably have the exact same lifespan.
I always find this topic so interesting especially because Chilchuck is technically middle aged by the terms of his society, so even if mentally he might actually be younger than what a lot of people scratch him up to be (like 50) he still has a maturity grown from cultural norms and perspective. In short words: the dude could equate to a 36 year old but in his pov he’s 45 (very different).