I think the better solution is to let them start paying for their own health care costs ---one way would be to have insurance plans that match the needs of the buyers. If you use little health care, then you should be in a low-user group with low premiums. If you want an extravagant policy then you should pay for it.
I think we need to get away from the idea that health care is something the government can do for you, or that health care is only going to doctors for medicine and surgery. Health care is really a do-it-yourself program, you have to eat and drink right, exercise and all the rest. Getting to be 400 pounds and then thinking there's some magic cure out there for your heart and other problems that you don't have to pay for is just bad thinking.