NEW YORK — New York City's crackdown on big, sugary sodas is staying on ice.

A mid-level state appeals court ruled Tuesday that the city's Board of Health exceeded its legal authority when it voted last year to put a 16-ounce size limit on high-calorie soft drinks served in restaurants, theaters, stadiums, sidewalk food carts and many other places.

In a unanimous opinion, a four-judge panel of the state Supreme Court Appellate Division said that while the board has the power to ban "inherently harmful" foodstuffs from being served to the public, sweetened beverages don't fall into that category. Soda consumption is not necessarily harmful when done in moderation, the court wrote, and therefore "cannot be classified as a health hazard per se."

The panel didn't address whether the size limit would have infringed on personal liberties, but said that in adopting it, the health board improperly assumed broad lawmaking powers given only to legislative bodies, like the City Council.

Mayor Michael Bloomberg, the driving force behind the regulation, promised a quick appeal.

"Today's decision is a temporary setback, and we plan to appeal this decision as we continue the fight against the obesity epidemic," he said in a statement.

The American Beverage Association, which had been among the groups challenging the rule, applauded the ruling, which was the second to find that the Board of Health had overstepped its authority. A similar lower court ruling in March kept the regulation from taking effect.

"With this ruling behind us, we look forward to collaborating with city leaders on solutions that will have a meaningful and lasting impact on the people of New York City," said Beverage Association spokesman Christopher Gindlesperger.

New York's effort to cap soda portions has drawn praise from health experts lauding it as a groundbreaking step in America's war on extra weight and ridicule from late-night TV hosts ribbing the mayor as a nutrition nanny.

The drinks limit follows other Bloomberg efforts to nudge New Yorkers into better diets. His administration has forced chain restaurants to post calorie counts on menus, barred artificial trans fats from restaurant fare and challenged food manufacturers to use less salt.

Bloomberg and city Health Commissioner Thomas Farley saw soft drinks as a sensible next front in a necessary fight: reining in an obesity rate that rose from 18 to 24 percent of adults in the city within a decade. Studies have tied heavy consumption of sugary drinks to weight gain. A 20-ounce Coke packs more calories than a McDonald's hamburger. Diabetes, linked to excessive sugar intake, is now among the leading causes of death in New York.

Bloomberg leaves office at the end of the year, and it is unclear whether his successor will continue the legal fight. Only one candidate, Public Advocate Bill de Blasio, supports the ban. City Council President Christine Quinn, another candidate, has said she believes the city has the right to impose the ban, but wouldn't have done it herself. All the other leading candidates oppose it.

Many city residents view the drink limits as well-intentioned but too big of a reach into private conduct.

"Obesity is a big problem in our society, and that's where all the impetus for this comes from," said Francesca Delavega, 26, who moved to the city three years ago from Minnesota. "But I think people in New York also like being able to do whatever they want. And that's kind of one of the things we're known for."

Writing for the appeals panel, Justice Dianne T. Renwick did leave a slight crack in the door for some type of restriction on beverage sizes.

Nothing in the decision, she wrote, is intended to "express an opinion on the wisdom of the soda consumption restrictions, provided that they are enacted by the government body with the authority to do so."