The Global Soda Tax Experiment

“It’s really hard to shift these behaviors, and taxes are, if not the single most, one of the most impactful and important policies to move the needle on unhealthy eating habits,” says Christina Roberto, a behavioral scientist at the University of Pennsylvania in Philadelphia. Taxes have helped to reduce the public health impact of alcohol and tobacco, and many public health researchers say there’s good reason to think they can mitigate the harms of sugary beverages, too.

At the same time, there are also reasons why soda taxes might not have the impact on public health that advocates hope for. The current taxes may be too low to affect purchasing behavior. People could switch to other unhealthy foods. Or, in some cases, they could simply buy their soda in a neighboring city that doesn’t tax them.

Definitive answers won’t come fast: Chronic conditions like obesity and diabetes take years to develop, and so, too, will any health benefits resulting from a new tax. But an emerging body of research suggests that beverage taxes have already reduced consumption of sugary drinks in some communities — an encouraging and essential step.