That poor mother with two kids is disproportionately likely to be overweight or obese, and that $25/week of soda is only making things worse. Due to medicaid/SCHIP, her health care costs are the problem of all taxpayers.
It doesn't bother me to force her to internalize some of the costs she is inflicting on me.
Similarly, I don't mind taxing polluters in proportion to the pollution they emit.
(As of 2014, this argument applies to all Americans.)
It doesn't follow that fat people incur more medical expense just because they're less healthy. Most healthcare expense is incurred while elderly, and the younger you are when you die the less it costs to treat you throughout your life. With regards to tax revenue, the ideal time for you to die is right after retirement, and the obese come much closer to approximating this than the thin.
Good, and bleak, point about dying once you retire.
I wonder how retirement costs compare to lifelong cost of being obese. According to stats cited by the CDC (http://www.cdc.gov/obesity/causes/economics.html) about 9.1% of medical costs can be attributed to treating conditions associated with being overweight or obese.
This is the problem with this form of healthcare. First we insist on socializing these costs then the socialization of costs is used as justification for meddling in the details of other people's lives. After all, as you said, now it's inflicted on you. Since respecting individuality and autonomy is only important to a tiny percentage of the population I don't see it getting any better either.
This is the problem with ALL health insurance, national or not. Unless everyone starts paying for everything out of pocket, some will take more than their 'share'.
To make a larger point, the problems of others are your problems as well. If I never have kids, an education system isn't something I should be concerned with by this logic, yet I'd hate to live in a country without a public one.
With health insurance, some will take more than their share by chance. Everyone will pay their actuarial cost (i.e., the expected value of their future medical expenses), and fat people will pay more. I.e., if the average fat person has average medical expenses of $3000, and the average thin person has average medical expenses of $1000, the thin person pays $1000 and the fat person pays $3000. I don't care what you do, since you will pay your own average medical costs.
With health insurance where costs are regulated (such as obamacare or our current employer provided health care), both people will pay $2000.
It doesn't bother me to force her to internalize some of the costs she is inflicting on me.
Similarly, I don't mind taxing polluters in proportion to the pollution they emit.
(As of 2014, this argument applies to all Americans.)