I don't think I'm the only one judging by this article:
ADHD can make it hard for us to remember - and want - to take care of basic needs because of our usual challenges with prioritization and distractibility.
People with ADHD have reported forgetting to do things like eating, showering, and going to the bathroom.
Forgetting to tend to your basic human needs can be caused by a poor working memory, hyperfocus, and time blindness.
Anyone can experience these symptoms, as they're not exclusive to people with ADHD and/or autism.
My goodness, you described me... I literally just had to move my leg because of pins and needles, and I have a flosspick hanging out of my mouth. Little habits like that help me stay on track health and hygiene-wise. I also brush my teeth several times a day, so if on occasion I forget to do it before bed, I at least brushed them after dinner or something.
I'm sorry you had to go through surgery and health issues. It's a reminder of how many facets of our lives are affected by ADHD. Medicine is helpful indeed, but I think you hit the nail on the head: we formed all these habits, and our brains will always go with the path of least resistance. I've had to learn to take pauses during the day and check in with myself to stay healthy and not burnt out. Still learning!