Several practical questions should be considered before introducing higher insurance rates for fat people:1) How is a self-imposed/self-caused obesity to be defined, and how is it differentiated from the obesity caused by medicaments, hormonal treatment, problems with lymphatic vessels etc.?2) How often are the clients weighted in order to adjust the insurance accordingly?3) Do you charge more obese people who for some reason do not seek for a medical help with their problems?4) What is the justification for comparing smoking and obesity?5) According to this logic, it would be perhaps necessary to charge more also: anorectic (or just too slim) people, people with diseases in the family, people with high blood pressure, people with low blood pressure, people that have stressful work (how do you measure it?), pregnant women, frustrated men...6) Should the generally healthy people pay nothing? (That would contradict the whole idea behind social welfare: health insurance and pensia payments are based on the rational - I now pay for the older generation, when I get old, the younger will pay for me. I now pay for those who need the health care, they will pay for me when I need it. There is an imposed idea of solidarity. If you do not want to be part of this imagined community, leave the country for a country with no system).And who does decide about all this? In a private health system it would be justifiable, because the insurance companies are just offering their services. In a system with some state involvment, I would argue it would be inappropriate.In general, I agree it is better not to smoke and to have a healthy lifestyle.
My main argument is that obesity is primarily the problem of the obese person. It does not really make a difference why they are obese, if it is genetic or bad habits - they need a more expensive product, and they should pay for it. The same would go for any other identifiable high-risk factor.The practical issue, e.g. how often to weigh them, is a matter for the insurance companies to work out. It does not affect the discussion of whether or not fat people should pay more.Generally healthy people should pay a fair price for the insurance of healthy people. It would not be nothing, but it would be far less than what unhealthy people pay. As you said at the end, all of my arguments are mostly relevant for a private insurance system, and get very messy in a government controlled system - but this is just another argument against a public health insurance. Government-managed insurance will necessarily be a system where healthy people subsidize less healthy people.As for the idea that the next generation should pay for the older generation, it is simply unenforceable. What happens to the people who payed for the generation before them, but then the next generation comes and votes against public health insurance, leaving them with nothing? What happens if there are far fewer children in the next generation, and they cannot afford the full cost of medical care for the previous generation? In the end we will have to force people to have children, and not let those children vote.