In March 2008, San Francisco required restaurants to list nutritional information on menus. Before the year was over, California became the first state to follow suit. The policy became national in December 2016.

One of the main reasons California has pushed for nutritional labeling is the rising rate of obesity, which is linked to many health problems.

National obesity rates

For 50 states and the District of Columbia

Obesity in California

The portion of California’s population considered obese grew from 9.9 percent in 1990 to 25 percent in 2016, with the rate leveling since 2010.

Obesity rates by California county:

New national standards

Studies show that about one-third of the food Americans eat is from restaurants. California’s requirement that restaurant chains with 20 or more establishments include calorie counts for food on menus will become a national policy in May. Many restaurants already include the information.

Where you will see calorie labeling:

Meals at sit-down restaurants

Foods purchased at drive-through windows

Takeout food, such as pizza

Foods, such as made-to-order sandwiches, ordered from a menu or menu board at a grocery store or delicatessen

Foods you serve yourself from a salad or hot food bar at a restaurant or grocery store

Bakery or coffee shops

Popcorn purchased at a movie theater or amusement park

A scoop of ice cream, milkshake or sundae from an ice cream store

Foods in covered vending machines also will have to carry calorie labels that can be viewed before purchase (with some exceptions).

New labels

New nutrition labels may go into effect in July for businesses with more than $10 million in annual food sales. A proposed extension for the compliance date has not been ruled on by the FDA.

Serving-size changes

One of the biggest differences in the new label is a more realistic reflection of modern serving sizes. A pint of ice cream might say four servings on the old label, but the new label will say three.

Packaging

Packaging size affects how much people eat and drink. The new labels will make both 12- and 20-ounce bottles one serving, since people typically drink a whole bottle in one sitting.

The U.S. Department of Agriculture has a chart showing daily caloric intake recommendations.