[frank ballenger]

The ones who make it into their 90s were thin, or fit,

There's a lot of evidence you are right. Elderly grossly overweight people are rare--probably for a lot of good reasons.

Zig Ziglar used to advise people to ask their slender doctor for weight loss advice. And if their doctor is actually fat, get a new doctor fast.

His doctor said in his office: "With my diet you will be happy to learn you can eat everything you want." Then he pulled out a sheet from his desk. "This is a list of everything you're going to want to eat."

[Doctor Congo]

“The ones who make it into their 90s were thin, or fit,”

Leon Askin is an exception. (General Burkhalter)

He lived to be 99 somehow.