Chain restaurants countywide are one day into a new requirement to provide nutrition information with their menus as part of an effort by King County health officials to improve the eating habits of the public.

Nutrition menu labeling went effect Jan. 1, requiring restaurants that are part of chains with 15 or more national locations to post calorie, saturated fat, carbohydrate and sodium information on menus and menu boards at or before the point of ordering.

In the coming weeks, the Seattle-King County Public Health Department will launch a public-education campaign about menu labeling. Advertising in public buses and radio public service announcements in English and Spanish will encourage customers to read menu labels and make healthier choices. The campaign focuses on consuming fewer calories, since higher calorie intake is more closely associated with obesity and related chronic diseases, officials said.

“Having nutrition information available to customers is an important step in reducing the obesity epidemic in King County,” said Dr. David Fleming, the Health Department’s director. “One way they can take charge of their health is by reading menu labels and making healthier choices.”

There are about 1,550 restaurants representing 160 chains in King County. Health officials worked with the establishments’ representatives, including their corporate headquarters, on how to post information on menus and menu boards. The restaurant industry had more than 2,800 questions about the issue, including how to comply with the rules, according to the Health Department.

Anthony Anton, president of the Washington Restaurant Association, an industry organization, said the group hopes the new regulations “will have a positive health impact” on county residents.

The regulations, some of the first in the nation, were approved last April by the county Health Board but were delayed until this month so restaurants could put them into effect.

According to the Health Department, many people eat a third of their calories away from home and spend nearly half of their food budget in restaurants. Some of that food is high in sodium, fat and calories, all contributors to obesity, heart disease and diabetes. Related county health statistics include:

• More than 719,000 King County residents are overweight or obese.

• Heart disease is the second-leading cause of death.

• The rate of diabetes nearly doubled in a 10-year period.