Seattle Mayor Ed Murray wants a tax on sodas and other sugary drinks, in part to reduce consumption and improve health.

Share story

At the start of 2016 only one U.S. city had imposed a tax on soda and other sugary drinks: Berkeley, Calif.

By the time we ushered in 2017, six other jurisdictions had joined the club — including San Francisco, Philadelphia and Cook County, Illinois, which includes Chicago.

Mayor Ed Murray hopes Seattle will keep the momentum rolling. Murray has proposed a tax of 2 cents per ounce on sugary drinks, with full details to come next month when he sends legislation to the City Council.

Murray has given two reasons for the tax on sodas, energy drinks, sports drinks, sweetened teas and more: improve health by reducing consumption of sugary drinks, and fund education programs aimed at improving the graduation rate of minority youth.

Most Read Stories

Unlimited Digital Access. $1 for 4 weeks

The mayor even compared sugary drinks to tobacco, saying “sugar is as bad as cigarettes in how we consume it,” on The Seattle Times’ politics podcast.

Are the drinks really that bad? Would the proposed tax reduce consumption? And why are diet drinks excluded from it?

A preponderance of scientific evidence links sugary drinks — and their chief offender, added sugars — to obesity, tooth decay, diabetes and heart disease. The World Health Organization, American Heart Association and Centers for Disease Control and Prevention (CDC) agree.

“Americans are eating and drinking too much added sugars which can lead to health problems such as weight gain and obesity, type 2 diabetes, and heart disease,” according to the CDC.

Most added sugars come from processed foods. Sugar-sweetened drinks, often containing high-fructose corn syrup, are a prime source. They account for 46 percent of the added sugars we consume.

Evidence from controlled experiments shows that too much added sugar leads to obesity, which increases the risk of diabetes and heart disease, said Dr. Jim Krieger, a University of Washington professor and executive director of Healthy Food America (HFA). The Seattle-based nonprofit has provided technical support for sugar-tax proposals across the country. HFA is primarily funded by the Laura and John Arnold Foundation, based in Houston, Texas, Krieger said.

Evidence that sugary drinks cause diabetes or heart disease is not as ironclad, as it’s based on research showing links rather than causation.

So how much sugary soda is too much?

The average can of soda contains about 150 calories, almost all from added sugars, according to the Harvard School of Public Health.

The American Heart Association recommends no more than 100 calories of added sugars per day for women and 150 for men. That’s less than a sugary drink per day considering other added sugars — such as cane sugar, corn sweetener and molasses — we consume in variety of foods.

About half of American adults drink a sugary beverage every day. Two-thirds of American youth have one a day; 30 percent have at least two.

Based on published research, Krieger’s HFA says daily consumption of sugary drinks:

• Increases the risk of tooth decay by 31 percent.

• Increases the risk of heart attack by 19 percent.

• Increases the risk of type 2 diabetes by 26 percent. Hispanics and blacks consume more sugary drinks than other racial or ethnic groups; they also have higher rates of diabetes.

•Increases the risk of obesity for children by 55 percent.

Why not burgers and fries?

Sugary-drink taxes are misguided, said Lisa Katic, a dietitian and consultant to the food and beverage industries.

The drinks account for about 7 percent of average daily calorie intake for Americans, according to the CDC.

Katic asks why they’re being singled out for a tax when too many Americans eat too much and don’t exercise enough.

“Why are we taxing sugar-sweetened beverages when most of our calories come from burgers and sandwiches?” she said. “I wish we could look at the big picture. If only we could focus on what we eat, portion size and cooking at home.”

Even if added sugars are a problem for some people, she said, sugary drinks don’t account for most of the added sugars Americans consume.

The drinks have become a simple and trendy target, she said. “A 12-ounce can of beverage is much easier to target than a burger and fries,” she said.

But burgers and fries have nutritional value, and added sugars don’t. That’s one reason the drinks are being singled out.

“I’m not going to say they have nutrients,” she said. “But they can fit into a balanced diet.”

Still, why not try to decrease the risks of diabetes and heart disease that sugary drinks have been linked to?

Katic said some of the conclusions about risk are based on correlations, not proven causation, so we should be careful about putting too much stock in them.

A spokesman for the Washington Beverage Association (WBA) agreed with Katic’s main points.

“The WBA wants the same goal of improved public health for Seattle residents, but we should not be singling out soda when we know that it is not driving obesity rates in Seattle or anywhere,” Jim Cullinan said. “Obesity has been going up for years at the same time (full-calorie) soda consumption has been going down.”

Adam Drewnowski, a UW professor of epidemiology and director of the UW’s Center for Public Health Nutrition, said he takes a more populist view of soda taxes.

“With the various problems that the minorities and the poor face these days, sugary beverages may be the least of it,” he wrote in an email. “But yes, it is easier for the upper classes to frown on empty calories than it is to address the real problems of food insecurity, employment, housing, schooling, or health insurance.”

Changing behavior?

Murray’s proposal would not tax diet drinks. Some have suggested that’s unfair because affluent whites tend to drink more diet soda, with artificial sweeteners, than drinks with added sugars.

“The bottom line is that the long-term health effects with artificial sweeteners is unknown,” Krieger said. Some studies haven’t picked up added risks; others have found an increased risk of diabetes; still others have suggested they might prevent weight gain, he said.

The debate is reflected in this new generation of sugar taxes. Philadelphia and Chicago included diet drinks in their tax. Berkeley, San Francisco, Oakland, Boulder, Colorado, and Albany, California, did not.

Murray’s stated goals are to deter consumption of sugary drinks and add about $16 million a year in education funding.

Taxing diet drinks would add more money but isn’t likely to benefit the health of those who consume the most sugary drinks, Hispanics and blacks.

Krieger’s group has a “research brief” about diet drinks, or artificially sweetened beverages (ASBs). It concludes: “Compared to sugary drinks, the science on ASBs in still in its infancy.”

Krieger is confident that Murray’s tax is high enough to change consumer behavior. Levied on distributors of sugary drinks in Seattle, it would charge 24 cents on a can of soda that retails, on average, for $1.17; that’s a 21 percent tax, according to Krieger.

Murray’s tax would be 40 cents on 20-ounce drinks that retail for $1.89. That’s a 22 percent tax.

“That will clearly have a significant impact on consumption rates,” Krieger said.

He bases that conclusion, in part, on a recent study of Mexico’s one-peso-per-liter sugary-drink tax, which runs about 10 percent. A study published last month in the journal Health Affairs found that consumption of sugary drinks declined by an average of 10 percent last year.

A study in Berkeley found that consumption of sugary drinks in low-income neighborhoods dropped 21 percent after the city imposed its one-cent-per-ounce tax.

Murray’s tax would be twice as high as those in Mexico and Berkeley, Krieger noted.