At BMI = 19 I'm probably pretty close to my high school weight.
May 2024 will be the 20-year anniversary of my May 2004 "weight loss experiment", when I dropped from BMI = 22 to 19 over five months just to see what it was like to be on the low end of what the CDC considers healthy. I liked it so much that I've never gone back. This experiment was prompted by mega-corp demanding that I go on medication due to borderline high blood pressure. I haven't had any problem with blood pressure since.
Just today for the first time ever I went searching for a photo of a healthy "older" male body to supplement the photo of a morbidly obese man that I've used for years as inspiration (the self-talk: you definitely DON'T ever want to live inside a body LIKE THAT). I found a good photo online. Recently I've been discouraged by how little I'm "allowed" to eat to maintain a BMI = 19 body as an "older" male (basically, one major meal per day is sufficient). I hope that the new photo will provide additional inspiration.
BTW: how many human males make it into their low 60s with zero chronic physical or mental health conditions of any kind? I've been thinking about creating a meetup group for exceptionally healthy older folks. Unfortunately, when my first chronic medical condition emerges I would have to drop out of my own group.