@arrados yes i agree there certainly isn’t a one size fits all, but the most important thing that you said is:
move around a lot.
Many people unfortunately can’t or don’t want to.
Now imagine you can’t move around a lot!! Do you think you could eat what you want.... I suspect not otherwise the pounds would pile on.
The thing about a lot of these illnesses is they creep up on you and pounce when you least expect it. As is the case with diabetes, many people could be prevented from developing diabetes if they were tested properly for the underlying cause, but i will leave that for another post!!