The FDA on Thursday said it will give chain restaurants and other establishments until December 2016 -- a year longer than initially proposed -- to post calorie counts on their menus. (iStock)

Want to know how many calories are in that slice of delivery pizza or movie theater popcorn? Sit tight. America will elect a new president before menus across the country are required to feature detailed calorie counts.

The Food and Drug Administration said Thursday it will push back the deadline for chain restaurants, grocery stories and other establishments to post calorie counts on their menus. The businesses now will have until Dec. 1, 2016, a year longer than the FDA initially proposed.

The move comes amid persistent pressure on the agency from various corners of the food industry to delay enforcement of the rules. The FDA said that since February, it has received numerous requests from for a postponement, including from groups such as the Food Marketing Institute, the National Association of Theater Owners, the American Beverage Association and Publix Super Markets.

The agency said industry officials cited the need to develop software and other systems to help create accurate nutrition labeling, as well as the time and effort involved in installing menu boards and training staff about the new requirements. This spring, dozens of lawmakers, including some staunch supports of menu labeling, urged the agency to push back enforcement of the new regulations.

"The FDA agrees additional time is necessary for the agency to provide further clarifying guidance," Michael Taylor, the agency's top food safety official, said in a statement Thursday.

[Calorie counts: Coming to a restaurant, movie theater, vending machine near you]

Last November, the FDA issued long-anticipated rules that would require most chain restaurants, vending machines, grocery stores, coffee shops and other places that sale food and drinks directly to consumers to display detailed calorie information on their menus.

The rules, which the agency first proposed in 2011, were included in a little-noticed provision in President Obama's landmark health-care law. The legislation directed regulators to fashion rules requiring food establishments to post calorie information on their, but exactly which retailers would be subject to the law has been the subject of much lobbying, debate and delay.

The agency gave initially gave establishments until December 2015 to comply. Some chains, including McDonald's and Starbucks, already post calorie counts on their menus.

Public health experts who have pushed for the regulations bemoaned yet another delay, saying the new rules already are long overdue and that the postponement will allow the food industry to continue lobbying to weaken them.

"This is a clear win for the restaurant lobbyists," said Marion Nestle, a prominent nutrition expert and public health professor at New York University. She noted that New York City had instituted menu labeling laws in 2008, and that Congress voted in favor of similar rules in 2010. "It really takes 6 years to figure out how to do something that was done in New York City in 2008?"

At the same time, some in the food industry welcomed the latest delay. Lynn Liddle, executive vice president of Domino's Pizza and chair of the American Pizza Community, which represents the nation's biggest pizza chains, said the agency's delay confirms the "serious deficiencies" of the new rules.

"Unfortunately, FDA proceeded with an approach to final rules that impose significant compliance costs without achieving any meaningful improvements in consumer education," said Liddle, whose industry has been among the most vocal opponents of the new regulations.

Whenever they go into effect, the new calorie-posting requirements will apply to restaurant chains with 20 or more locations, but not to smaller independent establishments. Regular menu items must have calorie counts, but daily specials don’t have to. Some types of alcohol on the menu are covered, but mixed drinks at the bar are exempt.

Prepared foods at grocery stores and delis must contain labels, but items intended for more than one person — a pan of potato salad or a tray of sliced meat, for example — are exempt. Pizza parlors must list calories, even when it involves online ordering, but the FDA has said it will allow posting of estimated calorie ranges, rather than requiring exact figures, given the many combinations of toppings. Vending machines also will have to include calorie information for items on placards or digital displays.

The FDA said Thursday it plans to issue additional guidance this summer on some of the most commonly asked questions businesses have asked about complying with the new rules.

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