A fast food tax, through higher prices, would deter Americans from consuming as much fast food as they currently do. Although this would not likely have a direct impact on obesity in the U.S., it would ultimately indirectly curb it through less consumption of fast food, assuming, of course, that consumers seek out healthier alternatives in the absence of fast food.
A fast food tax would help curb obesity because the increased cost would discourage people from ordering as much. One of the advantages of fast food is that it is cheap; increasing the overall cost of fast food would reduce its overall consumption, which should translate into less obesity in America.
Most people quickly develop a habit of eating fast food. Many people enjoy the taste of fast food and indulge their cravings for something sweet or salty. People also enjoy the convenience and speed that fast food brings to everyday life. Most people would pay a fast food tax to continue to enjoy their favorite fast foods.
Fast food is not the only contribution to obesity. Growing costs of healthy food, increased amount of work time, increased amount of time at a desk and many other factors are also at play. Although a fast food tax could be implemented to pay for universal health care quite easily, it would likely not curb obesity without a multi-faceted approach to tackle more than one contributing factor.