Nope. It's plump cheeks, as Lorraine says.
Nowt to do with cheekbones because when muscle goes you are left with hawkish hollow cheeks.
If you keep your natural fat content on yer face (basically retain collagen for as long as possible) you can keep young-looking.
Facial exercise helps too to maintain muscle mass and form.
I know being overweight helps because quite a lot of fat people look facially younger than their years. So, if a face is plump due to excess weight, then yes, that works Sorry, good bone structure is
a factor and having good cheekbones helps I don't mean razor-sharp, I just mean having a structured look to your face, rather than that baby-doll face previously mentioned. You'd only be left with hawkish hollow cheeks if you were too thin anyway.
I have high-ish cheekbones, and trust me, they're keeping everything propped up and everyone says I look younger than my age (45). My dad also has the same cheekbone/facial structure and at 71 he looks nowhere near that either. No hollow look for either of us.