A common denial response to the suggestion of improving one's wellness is to reply with something like this...
"Yeah, well, I gotta die someday. And my dad smoked and drank and ate bad foods for his whole life and he lived till he was 92. So, I'm not going to waste my time quitting smoking when it won't make any difference!"
The opposite is also widely accepted...
"Every adult male in my family died of heart disease before the age of 50---so I'm doomed anyway. There's nothing I can do."
I don't give much of a response to things like this, and chalk it up mostly to a lack of readiness. I understand where it comes from. But I'd like to expand on it and answer it here.
We all have certain genes, passed to us by our parents. Some genes are turned on and some are turned off at any given moment. What we do and how we live serve as inputs for us---which genes are expressed and which are not. All of our habits---what we eat, how we feel (emotions), and what we do for exercise, help to determine our gene expressions.
Look at this as a chance to neutralize the icky genes by how you act, and maximize the healthy genes. If you're the guy with relatives who all died in their 40s, you're admittedly at a disadvantage. But if you maximize your gene expression through your lifestyle, you are working at "beating the odds." You can ask my Dad about this one---he took this approach and is 61, rode his bike 26 miles the other day, and just spent 10 minutes on the phone last night telling me how great he feels.