Taxing Soft Drinks

The New York Times endorses a tax on soft drinks to... magically affect current obesity rates. And I recognize the argument that such a tax could generate revenue. But I have yet to see anybody offer any evidence that it would actually affect obesity. For example,

• Is the consumption of soft drinks higher or lower in states with deposit laws?

• Is the consumption of soft drinks higher or lower in states that already tax them, such as in states that charge sales tax on soft drinks , or in Arkansas with its excise tax on soft drinks?

• Is there any evidence that overweight people, particularly overweight young people, drink more soft drinks than their peers?

Might it be more constructive to expand physical education in schools, and perhaps also nutrition education, rather than trying to blame a particular type of beverage for the manner in which we, as a society, have chosen to keep our kids sedentary and behind desks for the rest of the school day? Or by using pop machines in schools to subsidize school budgets?

Also, given that a lot of the soft drinks young people buy are purchased by the can or bottle out of machines - the most expensive way to buy soft drinks - why should we believe that a tax will appreciably affect their willingness to pay a premium for soft drinks? As much as they might want to do so, I have not seen that any vending machine company has successfully convinced a school to pull out its water fountains.

Finally, given that it's in no small part our nation's substantial subsidies for corn that allow the production of inexpensive sugary drinks and fast food, might it not make more sense to increase the cost of the end-product not by introducing a new tax, but by reducing or eliminating the corn subsidy?