Earlier in the year I was in hospital for a while, had to have surgery. I went in at 80kg and after 5 weeks was just under 66kg.
I’m 175cm tall, BMI 26.1 (technically over weight, but was very fit) down to 21.6, which is considered “normal” but I felt very skinny and unhealthy.
The BMI thing is a little bit bullshit, since it doesn’t map fitness level.
As for getting back to a healthy weight, take it slow, eat really healthy foods eat mostly nova 1 & 2 foods, some nova 3 and avoid nova 4 if possible.
Also if you have been on antibiotics while in hospital, eat ferments like kimchi or sauerkraut, maybe drink some kombucha to rebuild your gut flora. But take it slow as it can really mess you up if you dump too much in at once.
I almost exclusively make my own food so should be good on the nova classes (I’d never heard of nova before). When I got out of the hospital I learned to make my own yogurt too which I think really helped me recover from the antibiotics. As far as how healthy my foods are, idk, probably up for debate. While I do make my own food I’ve been resorting to higher fat and sugar dishes (mostly fat I don’t like sweet flavors much) to try and get enough calories to gain weight