There are a couple of problems with this that I can see.
1) How do you check if people are living a healthy lifestyle? It seems a little big brotherish if you're checking in a way that won't let them lie and a little foolish if you aren't checking and so they can lie.
2) The rich have the most time and money to live a healthy lifestyle. A lot of the lower poor don't have the time or money to go to the gym, live in poor quality housing and do not have the ability to buy the variety of food that the rich can. So the poor could be worse off under this system than the rich, which is a little backwards to me.
3) It completely and utterly screws over the people who live unhealthy lifestyles. These are the people (largely through their own doing) who need healthcare most. This entire system is basically 'get healthy or the system will leave you behind'. I'm a wee bit of a socialist so I don't actually believe in the system leaving anybody behind - even if its their own stupid fault that they're in that position.
I do agree with incentivising healthy lifestyles, I just don't believe that essentially abandoning the people who don't live one is the way to go about it.
If you can figure out a way to fix those problems though, it seems like an interesting idea.
