Will a Soda Tax Really Help People Consume Less Sugar?

By: Charlotte Fisher  |  EatingWell.com

coke bottle with coins in it

How could something that tastes so good be so bad for our health? While sugar does make life a little sweeter—and is fine as a once-in-a-while treat—most Americans consume almost twice as much added sugar per day as they should. Eating too much sugar can lead to obesity, diabetes and heart disease, so it's wise to keep an eye on the sweet stuff.

Related: 6 Swaps to Slash Added Sugars from Your Diet

But a sugar habit can be hard to break. So when the city of Berkeley, California, tried to tackle the issue by levying a one-cent-per-ounce tax on sugar-sweetened beverages in March 2015, critics predicted it would do little to deter residents from guzzling the soda, energy drinks and sweetened fruit drinks the tax targeted. But according to a new report published in the journal PLOS Medicine, the tax appears to be having a significant effect on purchasing habits.

The research study evaluated changes in beverage sales in the year following the tax's implementation. According to the report, sales of sugar-sweetened beverages fell by around 9.6 percent one year after the tax took effect, while sales of untaxed beverages—such as water, fruit juice, tea drinks and milk—rose by 3.5 percent. Total beverage sales also increased. The findings suggest that taxes on sugar-sweetened beverages may actually encourage consumers to purchase healthier options. Considering that one 12-ounce can of Coke contains 39 grams of sugar—and that the recommended daily sugar limit is 25 grams for women and 36 grams for men—choosing an unsweetened beverage over a can of soda could have measurable health benefits.

Video: Why Too Much Added Sugar Is Bad for Your Body

"It's a movement! Cities are catching on that they can raise revenue and improve public health—at least a bit," says Marion Nestle, Paulette Goddard Professor of Nutrition, Food Studies and Public Health at New York University. "Everyone would be healthier drinking less soda."

Although the study showed that the tax is doing what it's designed to do (reduce purchases of sugar-sweetened beverages), it didn't specifically assess health outcomes related to changed consumer behavior. Yet, obesity rates continue to rise in the U.S., with studies linking high sugar-sweetened beverage consumption to increased risk of obesity—especially in children. Consuming too much sugar has also been linked to greater risks for heart disease, high blood pressure and high triglyceride levels.

"To expect taxes to reduce obesity ignores the complexity of the issue," Nestle says. "Soda taxes help, but they can't do it alone."

Additionally, while residents of Berkeley consumed fewer sugar-sweetened beverages than before the tax went into effect, they purchased more untaxed beverages instead, particularly milk, yogurt smoothies and milkshakes. As a result, the average daily calories from untaxed drinks increased by 28 percent (32 additional daily calories per person). Even though dairy-based drinks are typically healthier options, it's still important to watch calories—and added sugar. And as a friendly reminder, water is always an excellent choice.

Related: 6 Surprising Sources of Sugar

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