Starting Monday, chain food outlets and supermarkets in New York City will have to provide calorie counts for prepared food items on sale.
The move, announced by Mayor Bill de Blasio's office Thursday, is an expansion of the city's health code, reports the Wall Street Journal. It applies to businesses with at least 15 locations across the U.S.
Major outlets like 7-Eleven or Whole Foods will have to provide the calorie count of standard prepared items on their menus, and they are also required to give customers more detailed nutritional information upon request. According to the Associated Press, the new rules will affect about 3,000 restaurants and about 1,500 food chains.
For more on food, watch Fortune's video:
Restaurant and café chains in the Big Apple have already been required to display calorie numbers on their menus since 2008, and to label high-sodium dishes since 2015—although the measure's effect has been questioned.
While New York adopted the latest rules in 2015, the Journal reports that they weren't implemented until now as city officials were waiting on the Food and Drug Administration to adopt similar guidelines.
"Every day that we delay is denying New Yorkers something that could improve their health," Dr. Oxiris Barbot from the city's Department of Health and Mental Hygiene told the Journal.