It doesn't work like that unfortunately.Yes, there is a chance that you will be in the 50% who don't live that long, but there is an equal chance that you will be in the 50% who live longer.
We're already below 50% because we're in the manual labour group, don't have private medical access and will be working beyond 65.
Then there's lifestyle choices associated with not particularly being very rich.
Then there's lifestyle choices associated with not being very well edumacated..
Then there's just plain dumb lifestyle choices...
It's not an equal playing field.