This Dutch study is one more coming to the same conclusion:
http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.0050029
Conclusions
Although effective obesity prevention leads to a decrease in costs of obesity-related diseases, this decrease is offset by cost increases due to diseases unrelated to obesity in life-years gained. Obesity prevention may be an important and cost-effective way of improving public health, but it is not a cure for increasing health expenditures.
Or to put it more bluntly, people who live an “unhealthy” life style die earlier and quickly – people with a “healthy” lifestyle live long enough to end up with Alzheimer’s and wind up in a nursing home for 20 years…
That’s not even considering the effect on the Social Security system. The medical system (and government’s) goal measures success by quantity of life, not quality of life. But no matter how hard medicine works, you will not live forever.