This type of possible bug has happened to me twice already. Probably it will happen every time a character vomits after overeating (after a sickness character can get healthy without any problems unless there is a bug concerning sick status).
Maybe it is a status bug or maybe it just works as designed but to be healthy again I need to die or maybe just get hurt a bit - it depends if vomiting procured by overeating reduces blood levels and health points as well.
It seems that it is reproducible so I will try to test it once again but I need to die first and my character is on since the last character saves wipe after some DDOS attack about 2 weeks ago.
Please let me know if I should test it more extensively.