Interesting. My anecdote comes from a slightly different angle. I've always been in very good shape, lots of weightlifting and cardio my whole life, and been a very healthy eater. But, the "spare-tire" was always there, even with muscles bulging underneath.

Just for kicks I decided to try Steve Gibson's recommendation to remove sugar and starch from the diet. (https://www.grc.com/health/lowcarb.htm)

No knee-jerk here please, this isn't one of those butter-bacon-cheeseburger things. Nope, I eat tons of fresh veggies, lean meats, all smothered in olive-oil, nuts/flax, etc. I do actually allow myself some treats on the weekends for sustainability.

Still, one month later, for the first time in 20 years I no longer have a spare-tire. It makes perfect sense now that I think about it. As long as you fill yourself with sugar/starch you prevent the body from being able to go into fat-burning mode. Eat too much (as is common) and you go into fat-storage mode.

Bread may have built civilization, but now it builds waistlines.