TOD:
A subject I'm very familiar with.
My weight gain began as a child when I was put on prednisone for allergies/asthma. When I was 10, I was a puffy little guy:
By the time I was ready to graduate high school, I clocked in at 325 lbs and a 50" waist:
(Flowing graduation gowns do tend to hide the flaws somewhat).
Between graduating high school and starting college, I went on The (original) Atkins Diet. My waist went from 50" to 32":
After that, I let nature take its course and stayed between 36" and 38" in the waistline, and now I can wear either a tailored 38" pants, or a more comfortable 40" pants.
This picture, from THE SECRET GARDEN, is one of my favorites; I think it was the last time I wore a size 36". . .