"Even if... You're gonna get old".

But.. that's not guaranteed.

It's guaranteed you'll die. Everyone does.

But growing old is a privilege that not everyone gets, and one of the best ways to help you to achieve that is... Taking care of yourself and your body, your health. Some things are out of our control, sure. Can't do anything about that. Control the controllables.

The OOP is missing the key point that no, not everyone is gonna get old, because some of us won't get that chance, and you're a hell of a lot less likely to if you don't look after yourself. This isn't some smart "gotcha, you'll be sorry when you've wasted your youth keeping in shape and not just eating whatever you like whenever you like! (As if that's the epitomy of living life to the fullest, anyway??)".

I'd rather miss out on a few cheesecakes here and there than.. you know...not make it to old age.

Side note: firm believer that part of feeling good is doing difficult things and achieving your goals - is your life really that fulfilled by over-eating and under-moving? Is having the self control of a five year old really what you want to be proud of - more than the people out there running marathons, lifting their bodyweight? (Not to put anyone down, losing weight is hard and those urges are natural, but part of growing as a person is learning how to delay gratification - and obviously you don't need to run a marathon or lift your bodyweight to achieve great things, just examples!)