About two days without food, a bit more if I remember correctly, and around one day without water.

I had to have a knee surgery with general anesthesia, so I wasn't allowed to eat several hours before and couldn't drink either. Due to the timing of the surgery the last time I would have been allowed to drink was like 1 am, but I'm a morning person and was anxious so I went to bed at my normal 10pm and also ate and drank at my normal 7-8pm or so. Or maybe I had to stop eating earlier, I don't remember exactly.

Anyway, the surgery happened, my parents picked me up and took me home. My mother had one of her many many meltdowns. They hadn't brought me snacks or drinks to the hospital and she just mocked me that I couldn't hold it together for the 1 hour ride home. We get home, I hobbled to my bed. My mother refused to bring me food or drinks and forbid my father from bringing me anything. I could come to the kitchen and sit at the table "like a normal person" if I wanted to eat. In the evening my spineles POS father at least brought me a bottle of water, much to my mother's dismay.

The next day I managed to hobble to the table, so I was allowed to eat and drink.

This wasn't entirely new, my parents had a habit of locking me up in my room without food or water for an entire day when I was little. They never thought that was a big deal. My mother even told me after the surgery that she wouldn't bring me food to not "enable my spoiled behaviour" and that it was a good chance to finally lose some weight. (I was just slightly overweight, maybe 80kg at 172).

In case you're wondering: yes, I've been no contact with my family for years.