New and compelling research no longer leaves doubt that sodas, both diet and regular, are a serious health risk, especially for children. The latest research is a large study by researchers at the University of California Los Angeles Center for Health Policy of 4,000 adolescents and 43,000 adults that directly links consumption of soda and other sugar-sweetened beverages with obesity. Which can be added to a list that includes diabetes and heart disease. That Americans drink an excess of these drinks, especially children, there is also no doubt. I cringe when I see young mothers come into my office with children drinking sodas, or drinking them themselves. We are a Coke culture. the medical cost of our soda habit (and I include all mass marketed sweet laden beverages) runs in the tens of billions, much paid for through tax dollars.

So kudos to the mayor of San Francisco for taking a small step in the right direction by proposing a tax on retailers that that sell the beverages. While I think a better approach is to tax the drinks directly, even this small first step is welcome.

While the idea of such a tax, like any new tax, gets people fired-up there are good reasons for this tax, and the chorus for it is beginning to swell. Of course, we can expect the beverage industry to fight with millions against any tax and the ads have already started running.

The reasons for a soda tax are many, and the issue recalls the smoking and trans fats battles, and there are arguable points on both sides.

Here are five good reasons for a soda tax.

Like any sales tax, a tax on soda will hit the poor hardest. Soda is cheap, being mostly a chemical brew of water, preservatives, flavorings, and sweetener. On the other hand, it is the poor who can least afford the empty calories and health results of reliance on soda as a “food”.

There are many unhealthy and sugary non-foods on the market, soda is the most advertised and prevalent, with enormous personal and social costs. Which is why it is well studied. While someone drinking a soda does not impact those around them directly like a smoker does with secondhand smoke, the long term health effects are a huge cost to taxpayers. This is a cost that should be addressed to those making the soda choice.