NEW YORK -- Labeling menus with calorie counts has little to no effect on consumers' food purchase selections, according to a survey conducted by the city of New York and the Robert Wood Johnson Foundation. New York was the first location to enact a menu-labeling law.

The survey, published in BMJ, looked at 15,798 adult customers in 2007, before the law went into effect, and then in 2009, after the law was enacted at various restaurants. Register receipts were reviewed to verify purchases.

The study revealed that calorie consumption actually increased slightly for the customers who visited restaurants in 2009. Those unaware of calorie counts purchased foods containing an average of 828 calories. Those who saw posted calorie counts averaged 846 calories per purchase.

Average calories per purchase shrank at three major fast-food chains in 2009: McDonald's, Kentucky Fried Chicken and Au Bon Pain. However, researchers noted all three chains changed their menu offerings to include more low-calorie options.

After posting calorie counts, restaurants specifically used one method to keep traffic strong at their locations: size and value were heavily promoted while nutrition was de-emphasized. According to the study, a prominent example of this was when Subway introduced $5 footlong sandwiches.

One factor from the study that could be a considered a positive for enacting menu-labeling laws was that 15 percent of customers surveyed in 2009 said they used the calorie information when making purchasing decisions. Those people purchased 106 fewer calories than those who said they didn't utilize the information.

However, Eric Finkelstein, associate professor of health services at Duke-National University of Singapore Graduate Medical School, told The Wall Street Journal that health-conscious consumers would be purchasing foods with fewer calories with or without the labeled calorie counts.

Menu labeling will soon go national under the health-care overhaul law.