None of the chains involved in the study included nutritional information on their menus, the researchers pointed out.
Meanwhile, a second study suggests that calorie labels on menus or on restaurant menu boards are effective in prompting people to buy meals with fewer calories.
That study, published in the June American Journal of Preventive Medicine, examined the impact of menu-labeling regulation in King County, Wash.
The researchers surveyed more than 7,300 people aged 14 and older who dined at 10 restaurant chains, including Subway, McDonald's, Taco Bell and Starbucks, before the law took effect, and again six and 18 months after the law was implemented.
Although no change in purchases was seen six months after the menu labeling law took effect, the study revealed that after 18 months, the average calories per purchase at chain restaurants fell by 38 calories, from 908 calories to 870 calories.
"Menu labeling is critical because Americans spend nearly half of their food dollars on foods prepared outside the home, which tend to be higher in calories and less healthy than what we eat at home," said researcher Dr. James Krieger, with Public Health--Seattle & King County, in the news release. "Over time, people seem to respond to the availability of information and use it to inform their purchases."
Visit the U.S. Centers for Disease Control and Prevention for information on balancing calories.
-- Mary Elizabeth Dallas
SOURCE: Robert Wood Johnson Foundation, news release, May 23, 2013
All rights reserved