He is probably trying to, correctly, imply that heart attacks at 51 are an anomaly given how much we know about heart attacks and how accurately tests can predict them. Especially for a person of the deceased's means.
The OP is also factually correct: "The current generation of American children may be the first not to live as long as their parents". [1] [2]
I didn't down vote you but I think your initial down votes were based on two things:
1) you stated your opinion as a fact. There is some research to point to shorter life expectancy but stating it as a fact that will happen no matter what seems a little strong.
2) you state that life expectancy will "plummet". Plummet indicates a very large dropoff. From what I've seen, some respected paper suggest that life expectancy might dip by a year or so.
But to have a say 10 year drop, which is what plummet would indicate seems rash as no credible scientists are predicting that.
The OP is also factually correct: "The current generation of American children may be the first not to live as long as their parents". [1] [2]
Fast food explosion is partly to blame.
[1] http://www.georgiahealthnews.com/2012/05/largely-preventable...
[2] I've heard this from at least 10 other sources first hand, especially health insurance companies.