It's generally agreed that ketosis results in bad smelling breath. Seems

to me that if paleo man ate so few carbohydrates that he was in ketosis
all the time, a preference for the smell of ketones on the breath would
have been passed down, rather than an aversion. If ketosis were the
healthier condition then those on ketosis would have lived longer and
had more offspring, etc. Sexual selection should mean that we would
consider that particular smell on the breath to be attractive, since
those would be the healthy mates most likely to provide surviving kids.
But from my limited experience, bad breath means less likely to have
sex, not more likely. Doesn't the very fact that ketosis breath smells
repulsive mean it's not the evolutionarily preferred condition?

John B