New York City's health department wants to require some restaurants to include the the number of calories their foods contain on their menus. Fast-food chains, however, are not in favor of the proposal.

The requirement would apply only to restaurants that serve standard portions and already disclose calorie information, typically on their Web sites or on fliers. Most fast-food chains fall into this category, and the city estimates the rule would apply to about one in every 10 restaurants.

Heath Commissioner Dr. Thomas Frieden said diners have a right to know which foods could potentially cause excessive weight gain.

However, John Whipple, president of the National Council of Chain Restaurants, said the proposal would be costly, and even unconstitutional. He also said it would penalize restaurants that voluntarily disclose nutrition information.

Whipple said in written testimony to the New York City Board of Health, "Restaurants should be encouraged in their health education efforts, not dissuaded from such effort by misplaced regulatory policies."

If the Board of Health approves the proposal, it will go into effect in July. The vote is tentatively scheduled for December.