Will a tax on soda end tooth decay?

The city of Philadelphia has proposed a 3-cent-per-ounce tax on soda and sugar-added beverages, potentially raising the cost of these drinks up to 60%. This goal of this sin tax is twofold: lower the incidence of obesity and diabetes, and provide money for universal public kindergarten. The government says the tax is the best way to reduce consumption of sugary beverages, while the soda industry says education is the answer. I'm wondering, how will this effect tooth decay?

Everyone knows that drinks high in sugar cause tooth decay. But what they may not know is that any food or beverage high in acid does the same. How is this possible? Acidic foods and drinks weaken the enamel of your teeth, and with repeated exposure, cavities develop. This is nearly the same way sugar destroys your teeth. Except with sugar, the normal bacterial residents of your mouth eat the sugar you consume and produce an acid byproduct that destroys your teeth. For more on this, check out the American Dental Associations video on Cavities.

What is the dental takeaway on this political issue? Sugary and acidic beverages should be consumed in moderation. Repeated exposure to these substances will destroy your teeth, no question. What you should take extra time to look out for are "sugar-free" products that can actually be highly acidic. For example, while Diet Coke is "sugar-free," it actually contains phosphoric acid, a potent acid that can be highly destructive to your teeth.

I ask my patients to follow a rule. The only drinks you should have between meal times are plain water, black coffee, or plain tea (no cream or sugar). If you want a sweet drink, consume it at meal time and never take it along with you. Not very exciting, but it works.