some people are that same size they were thirty years ago in HS, and some look nothing like it.
For example, Nicole Kidmann or the Rachel chick from friends seem to be aging without getting thick. Sure, some is working out and dieting, but that is just keeping fat off the frame. Others, say Princess Leia or Body Heat Turner thicken out the frame and get quite matronly.
I remember a guy whose dad was SF in Vietnam, and looking at his old pictures could not believe it was the same guy. Then I am cleaning out stuff getting ready to move, and somehow a pair of size 30 UDT shorts is still in a box of stuff. No way I must look like that guy anymore.
Anyways, we all know diet and exercise issues can lead to extra pounds.
Also, some people will gain weight on 2500 calories a day and others will lose it at baseline metabolism.
But how it is that peoples frames and faces get thicker while some others don’t is a whole different story.
Another example, Kirk vs. Spock. Kirk is hardly recognizable any more, while Spock was very recognizable till the day he died.