links.mimuki.net

So, apparently, there's a word for the ability to percieve and discriminate between your own [hunger, thirst, pain, bladder urges, arousal, etc]. And having a bad sense of that stuff is in fact a thing and not necessarily a personal deficit, or a skill issue, or a "stop eating so much sugar and you'll get better thirst cues" or anything like that.

It would also appear neurotypicals do not follow a diagnostic flow chart methodologically to figure this stuff out, and they "just know" with plenty of notice before it becomes a problem.

This explains a lot.

Some of the causes of olfaction problems are allergies, nasal polyps, viral infections and head trauma. [...] Lifelong hyposmia could be caused by or comorbid with Kallmann syndrome or autism.

See also: Dysosmia and Anosmia, which list an assortment of causes including fibromyalgia, Bell's palsy, depression, etc. Bodies are a mess, it seems.