I dunno. You know… my grandpa drank a 5th of whiskey a day and smoked one cigar a day until the day he died. Age 102. Sometimes I think that you enjoy the heck out of life and don't worry about anything. Shrug. I hope genetics matters more :)
Edit: I also didn't mean to imply that I think the key to a long life is simply not worrying. The key to a long life is definitely a combination of genetics and how well you take care of yourself. But part of taking care of yourself is worrying less.
And there's much, much more to life than longevity, like day-to-day quality of life. If you focus on that, then longevity is just a bonus, even if it's true that you have no control over it.
You certainly have control over quality of life, though. And indulgence tends to hamstring that for short-term gain.
I'm in my 30s which is apparently when all the chickens start flocking home to roost from lifestyle decisions. It's sad to see a 35-year-old seat-ridden at the beach because of a smoking habit and obesity, winded from tossing a football around. Not sure my friend feels like that's the road to "enjoying the heck out of life".
Surely the key to life is getting to a point where you aren't dependent on vices like sweets and alcohol and food so that you can partake on your own terms, exercising total dominance over yourself.
If I enjoyed smoking and drinking, I'd invest in that nutrition plan long before taking a stab at whatever the "scientists" and "nutritionists" are whoring out at the moment.