There’s no sense sugarcoating it: Philadelphia is one of the fattest big cities in the fattest country in the developed world. To its credit, it has been trying to shed the pounds -- back in 2001, its then-mayor enlisted the city’s basketball team in challenging residents to lose 76 tons in 76 days -- but very little has worked. That’s why Philadelphia’s decision to tax sugary drinks is so promising.

About one-third of Americans adults are obese, and obesity is a primary cause of diabetes, heart disease and other serious conditions. It’s one of the most urgent public health problems in the U.S., but reducing it requires bolder solutions than most public officials have been willing to embrace.

That’s now starting to change. In 2014, voters in Berkeley, California, adopted a tax on sugary drinks, and on Thursday, Philadelphia became the first large city to take the step. Others should follow.

The evidence in support of such a tax has been growing. In Mexico, purchases fell by 12 percent a year after it instituted a tax, and the biggest reductions fell among the poor, who -- in the U.S. -- are most likely to face obesity-related health problems.

A recent study found that prices in Berkeley have gone up, as hoped, since the tax passed. Some stores have stopped selling the sugary drink altogether. (Michael Bloomberg, founder and owner of Bloomberg LP, supported the efforts of soda pop tax advocates in Mexico, Berkeley and Philadelphia.)

And there’s another windfall: Philadelphia’s tax, 1.5 cents per ounce, is expected to generate $91 million in annual revenue that will be used to expand the city’s prekindergarten program; revitalize parks, recreation centers and libraries; and build new schools. These concrete antipoverty benefits, even more than the expected public health gains, helped win support for the tax.

In November, voters in Oakland, California -- and possibly San Francisco and Boulder, Colorado -- will decide whether to adopt a similar pop tax. More cities are sure to follow, and states won’t be far behind. After all, some state legislators are sure to ask: Why should cities, rather than states, reap the revenue?

The beverage industry spent heavily in Philadelphia to defeat the tax and even offered to finance the first year of preschool if the city council postponed a vote. Nationally, the industry’s opposition strategy -- minimize the links between its product and disease -- mirrors the one the tobacco industry pursued for decades. There is no reason to think it will turn out better this time, and the beverage industry risks the same fate: lawsuits and advertising bans.

The industry could adapt by making healthier beverages. The American Beverage Association’s initiative to reduce beverage calories by 20 percent by 2025 is a step in the right direction, but hardly sufficient.

The girth of a great nation cannot be reduced by the actions of a single industry or a single mayor. But it can be done -- and it starts with having the political willpower to apply the laws of economics.

Editorial
(Bloomberg)