And some people conversely live so hard their organs age prematurely. Pretty sure that's what the pathologist said about Errol Flynn after he carked it.
Very likely. Excessive drug consumption, poor diet, lack of sleep, etc. - it's all going to add up.
I suspect a lot of issues - being overweight, little exercise, eating too much sugar, or fats, smoking, high alcohol consumption, etc. are on their own often relatively modest issues. It's when people start to combine several of them that the risks start adding up. Well, not necessarily adding up, but
multiplying. If someone has a base 2% chance of stroke or heart attack in the next ten years, something that increases it 50% (i.e. to 3%) might be viewed as pretty trivial. Two of them, 4.5%. Three, nearing 7%. Four, around 10%. So things can mount up. And it's not just going to be that: chances are the risks of all manner of other things degrading or going wrong is also going up - kidneys, lungs, brain, liver, immune system etc. - which themselves might create additional risks.