In an ambitious pledge announced on Tuesday, the U.S. soda industry is committing to cut America's calorie intake from beverages by 20 percent over the coming decade. As part of the agreement, which was reached by the American Beverage Association and Alliance for a Healthier Generation, Coca-Cola, Pepsi Co., and Dr. Pepper Snapple Group Inc. will promote smaller portions as well as zero and low calorie offerings, and provide calorie counts on vending machines, soda fountains, and retail coolers.

"This is the single-largest voluntary effort by an industry to help fight obesity and leverages our companies’ greatest strengths in marketing, innovation and distribution," Susan K. Neely, president and chief executive of the American Beverage Association, said in a statement. "This initiative will help transform the beverage landscape in America."

In many ways, the soda industry's commitment is, at the same time, a concession.

The announcement, after all, comes on the heels of several attempts to curb soda consumption on both national and state levels. In New York City, beverage-makers thwarted an attempt to place caps on portions of sugary drinks. In Illinois, State Rep. Robyn Gabel proposed a soda tax that ultimately failed. And in San Francisco, a new tax on sugary drinks will be voted on in November. Even a national soda tax, however unlikely, was proposed just last month by Rep. Rosa DeLauro (D-Conn.).

And it's not just lawmakers are who increasingly wary of soda. Americans on the whole have been getting tired of the stuff for years. Soda consumption has been declining in the United States for over a decade.

Still, soda remains a big part of the American diet. Americans on average drank more than a can of soda per day last year (nearly one and a quarter, to be more exact), according to estimates by market research firm Euromonitor.

And that might be too much. Roughly a third of all added sugars Americans consume come from soda, energy drinks, and sports drinks, according to government estimates. "Rising consumption of sugary drinks has been a major contributor to the obesity epidemic," the Harvard School of Public Health notes on its website.

This is why pledging to cut beverage calories by 20 percent by 2025 is seen as an important shift in the right direction. Former president Bill Clinton, whose non profit charitable organization, The Bill, Hillary & Chelsea Clinton Foundation, helped found the Alliance for a Healthier Generation, called it "a critical step in our ongoing fight against obesity."

It's also why voluntarily committing to market and distribute smaller sugary drink portions is no small deal—it suggests the industry is more serious than some might suspect. The move, after all, stands to undercut sales of some of the industry's leading brands, including regular Coca-Cola, Pepsi, and Dr. Pepper. The plan is to promote bottled water and lower calorie drinks instead, which all three soda makers sell in bulk. But the reality is that each could see its respective businesses suffer nationally as a result.

While it remains to be seen how these promises play out, the announcement suggests that the soda industry has reached an epiphany: that it can no longer afford to ignore the fact that it's time to make some big changes.

Still, there's a lot more that the soda industry could be doing to promote public health, Michael F. Jacobson, executive director at the Center for Science in the Public Interest, said in a statement. For one, he said, the industry could drop its opposition to taxes and warnings labels on sugar drinks.

"We need much bigger and faster reductions to adequately protect the public’s health," said Jacobson. "Those taxes could further reduce calories in America’s beverage mix even more quickly, and would raise needed revenue for the prevention and treatment of soda-related diseases."