If new requirements from the Food and Drug Administration end up sticking, you could be seeing calorie counts for most things you eat outside the home — from vending machines to chain restaurants, movie theater popcorn to pre-made sandwiches at the grocery store.

The rules are meant to show Americans how many calories are packed into our favorite foods, as we consume a third of our total calories outside the home, reports the New York Times.

“This is one of the most important public health nutrition policies ever to be passed nationally,” Margo Wootan, director of nutrition policy at the Center for Science in the Public Interest told the NYT. “Right now, you are totally guessing at what you are getting. This rule will change that.”

Included under the rules are any food establishment with 20 or more outlets, which covers fast-food chains and sit-down restaurants; pizza chains; food in vending machines; amusement parks; prepared foods in supermarkets, grocery chains and convenience stores (if the food is meant to feed one person); and will even cover alcoholic drinks that are on the menu at establishments that serve food, but not, for example, a mixed drink at the bar.

The rules will go into effect a year from now, though we’re probably going to see plenty of legal and political challenges from certain parts of the food industry, including grocery stores and other places that make food for takeout.

The National Grocers Association said: “Grocery stores are not chain restaurants, which is why Congress did not initially include them in the law. We are disappointed that the F.D.A.’s final rules will capture grocery stores, and impose such a large and costly regulatory burden on our members.”

Vending machine operators were also trying to get out of the regulations, and will get an extra year from the FDA to comply with the new rules. Vending machines will have to show calorie counts on stickers or signs near each specific food for sale, or near the button to select it.

Sen. Tom Harkin, who helped create the labeling requirement in the law, said the rule “closely mirrors congressional intent.”

“This rule is consistent with our bipartisan agreement and will help to protect and strengthen access to healthy, nutritious foods for families around the country,” he said in a statement.

Many chain restaurants, like Panera and McDonald’s, already include calorie counts on their menu boards nationally. And in cities like New York, where chains have had to post calories on menus since 2006, or the 18 or so states that already have menu-labeling regulations, consumers are already used to this kind of thing.

Previously: Report: Chain Restaurants Have Cut An Average Of 60 Calories From New Menu Items

F.D.A. to Require Calorie Count, Even for Popcorn at the Movies [New York Times]

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