Whether or not to put the number of calories of a meal on the menu does not infer in the consumer’s decision.

Shortly after calories began to be posted on fast food restaurant menus, people cut back a little on what they ordered, but it didn’t last long.

Customers of fast food chains in Louisiana, Mississippi and Texas ordered an average of 60 fewer calories per transaction in the weeks following publication of the data, according to a study published Wednesday in the medical journal BMJ. That represented a 4% decline and was mainly for not ordering extras such as potato chips or desserts.

After about a year, the reduction was 23 calories.

Since the orders are likely to be for several people, the impact per person could be even less. However, the figure is an average, and some people may have made greater reductions while others did not, said study co-author Joshua Petimar of the Harvard School of Public Health.

[box type=”info” align=”” class=”” width=””]”The biggest impact may have been in the short term, while the long-term effects are still tentative,” he said.

It’s the latest study to measure how calorie counts influence what people ask for. A national law that went into effect last year requires chains with 20 or more locals to publish calories. Some places, such as New York City and California, imposed similar standards years ago to combat obesity. The idea is for the information to result in people making better choices.

Previous research indicates that calorie counts generate little or no change, and Wednesday’s study indicates that it appears to be the same in the South, where obesity rates tend to be higher. Still, the authors say the research is necessary to understand the effects of the practice, especially in the long term and in other settings, such as formal restaurants.

People may not notice the numbers on the saturated menus of fast food restaurants or not know what they mean, said Bonnie Liebman of the Science Center for the Public Good, who has pushed for calories to be included on the menu.

The number of calories needed varies, but a moderately active 40-year-old man typically needs 2,600 calories. Liebman said requiring restaurants to publish the figure is also a way for them to prepare less fatty dishes.

The findings were based on three-year sales at 104 fast-food outlets. The owner gave the information, but did not allow researchers to identify the chains.