A US regulation that went into effect recently directs chain restaurants to label calories on their menus, in an effort to encourage people to consume in moderation.
The rule, rolled out in 2014, applies to restaurants chains with 20 or more establishments that offer similar food items.
The targeted chains must disclose the number of calories contained in standard items on menus and menu boards.
Businesses must also provide, upon request, written nutrition information for standard menu items, covering fat, sugar, sodium and protein, according to the Food and Drug Administration (FDA) of the United States.
FDA Commissioner Scott Gottlieb said the new regulation is based on research which shows that when customers are presented with calorie information, they tend to choose food items that contain less energy, reports Xinhua.
"Studies suggest that access to clear and consistent information about calories in restaurant items can help reduce calorie intake, which over time could make a difference in obesity rates," he said.
Obesity has become a major health issue in US, leading to higher chances of heart disease. Studies show the US obesity rate, which continues to grow, remains highest in the world.
