My dad is a lucky man.
He has diabetes, heart problems, and goes for dialysis 3 times a week. But heck, he's a lucky man.
He's lucky because he has a family that takes care of him despite the fact that he could've easily avoided all these diseases if he would just take care of himself better.
When he was younger he's a multiple packs a day smoker. Stays up late into the night. Doesn't take care of his diet.
He was such a hardcore smoker that after having had bypass surgery, he solemnly promised not to smoke cigarettes again. He didn't. He graduated to cigars instead.
So yeah, he's a lucky man.
Lately I've been going through a healthy living phase. I've always been a bit paranoid about my health since I know I've always been a weakling with a shot immune system. Not to mention the fact that genetics-wise I'm fighting an uphill battle.
But I owe it to myself to take care of me. Besides, I won't know if I would be as lucky as my dad. He has people to fall back on when he's not feeling all too well. I on the other hand have a higher probability of ending up dying alone.
And even if I have people who would take care of me, I owe it to them not to be selfish in the sense that they deserve better than to spend their days taking care of a sickly being. People who take care of sick people are highly stressed individuals who need a support system of their own.
Of course, if you fall sick even though you've taken care of yourself decently enough that's just plain bad luck. But the fact of the matter is most sick people have been selfish pricks for having been abusing their body for years and then depending on others to take care of them.
If you really love your wife/husband/children/brothers/sisters... you OWE it to them to take care of yourself.