Aunty is pretty much right. Increased early mortality for obese people decreases their actual health care costs over time. The difference is only something like a 4% increase in health care costs. The cost in time and productivity lost to the companies or public sector jobs that the un-healthy people hold is not quantified.

My fat-tax idea was tongue in cheek, obviously. Although sin taxes are real, gluttony might be taking it too far. What I found anectdotally was that un-healthy people tended to spend more sick leave on actually being sick, rather than screwing off and having fun which is what I prefer my staff to do with their leave.

Another way the gov't could reduce obesity and save money would be to cut corn and soybean subsidies (will never happen). Try living a week by not eating something made with subsidized corn or soybeans, and you will find you are eating much healthier (feed lot beef counts).