Would you OK an diet-related morbid obesity tax and why?

I'm not thinking about those people who are obese because of a pre-existing condition like diabetes or a side effect of a medicine.But consider that most obese people are at a much higher risk of getting sick, while taxpayers-based health insurance like Medicaid must pay for their problems. So if you have a person who eats fast food junk everyday and weighs 300 pounds, should they pay some additional tax and why?