Reminding me of the infamous Polish study which considered costs across the social spectrum, government and university researchers in the Netherlands have issued a report in the Medical Journal of the Public Library of Science indicating that people who smoke or are obese live shorter lives and are less expensive to the health care systems of their countries.
Looking at the total statistics, the key here is their first table, which indicates that the costs of healthcare increase as people age. Based on this, they determine that the longer you live, the more expensive you are to the health care system. Obviously, this is an extremely simplistic model, so they attempt to correct for specific disease incidence by adding in additional "per disease group" costs based on specific health risks. These risks are based on per-year risks for each group and then extrapolated over the remaining lifetime of the individual in the model.
The most striking element to me was the difference between the "costs of other diseases" (which is where most of the additional costs come for the healthy people). Based on their research, the lifetime costs for the longer-living healthy people include a marginal increase in stroke costs against both smokers and the obese, a substantial increase in musculoskeletal diseases in comparison to the smokers (although less than the obese here) and a huge increase in "other diseases", which appear to be based mostly on the additional years of life. The smoker's 7 fewer years of life save €64,000, or about €9,100 per year. The obese person's 5 fewer years save only €41,000, or about €5,100 per year.
The most striking concern in my reading of the study is embodied in the second note on methodology: "Second, the health-care costs employed in the model were a function of age and disease status but not of proximity to death". Although they go on to state that because they've modeled the key causes of death that they have eliminated this problem, I find it difficult to believe based on what I've seen in the health care system in the United States. Now, clearly the Netherlands is a different beast because they have a mostly-socialized system of medicine, but it's hard to believe that the final years of life for healthy vs obese or smoking patience are actually that different.
All things considered, I'd much prefer a retrospective study based on lifelong medical costs or a comparable model based on proximity to death. The former is unrealistic because changes in health-care services and costs over a lifetime would be impossible to neutralize, so perhaps they should concentrate on the latter.
However, as with the Polish study of a few years ago, I don't think anyone is suggesting that it is cheaper for us to have people live longer. In the end, most people's longer lives come beyond their working years and at this point, the costs to welfare and retirement systems are certainly significant. As for whether it's less expensive for people to live healthier, that's going to require a lot more study, as productivity issues related to wellness and suitability for work aren't taken into account when health care costs are the only concern.