One in every six US consumers is reading calorie data on the newly introduced food labeling system, and is consequently buying products with fewer calories, US researchers reported in the BMJ (British Medical Journal). They describe this as a small but encouraging effect of the new legislation which came into force in New York in 2008.

The law requires restaurant chains with at least 15 branches to provide calorie data on menus and menu boards.

America is in the grips of an obesity epidemic, the authors explain. 17% of its children and one third its adults are obese. According to a significant number of studies, there is a link between the consumption of fast foods and high energy intake.

Apparently, consumers generally underestimate the number of calories in meals they order at restaurants. Before the new legislation, nutritional information on foods at the point of purchase was scarce.

Researchers from New York, and Santa Monica, California set out to determine what the impact of calorie labeling on foods might be on people’s energy intake at fast food restaurants in New York City.

Other countries are starting to follow suit, the authors add. In England high street chains are embarking on a similar scheme (voluntary one) – a part of the UK government’s Public Health Responsibility Deal.

They carried out surveys 12 months before the regulation came into force, and then again nine months after its implementation – spring 2007 and spring 2009. The surveys took place at 168 locations, all selected randomly, of the city’s top 11 fast food chains.

15,798 customers, all of them adults, provided register receipts and answered some questions. The researchers gathered information from 7,309 of them in 2007, and the other 8,489 in 2009.

Across the full sample no significant drop in calorie intake was detected. However, there were three significant reductions in three major chains.

Examples of what happened at the three chains, which made up 42% of the people in the survey, are highlighted below:

  • McDonalds – 5.3% drop in average energy per purchase
  • Au Bon Pain – 14.4% drop
  • KFC – 6.4% drop

Subway surprised with an average energy content increase of 17.8%. Subway aggressively promotes large portions.

15% of the surveyed customers said they used the calorie information, these customers bought 106 fewer calories than the others.

Apart from calorie information, the authors wrote that..:

“Special attention should be focused on educating customers on how to interpret and use nutrition information.”

Dr Susan Jebb from the MRC Human Nutrition Research Centre, Cambridge, England, comments that labeling is a good move, a good start, but there must also be changes in food supply.

Dr. Jebb said:

“Calorie labeling will help consumers make an informed choice about what they eat, but sustained improvements in the nation’s diet will require a transformation of the food supply too.”

“Changes in energy content of lunchtime purchases from fast food restaurants after introduction of calorie labeling: cross sectional customer surveys”
Tamara Dumanovsky, Christina Y Huang, Cathy A Nonas, Thomas D Matte, Mary T Bassett, Lynn D Silver
BMJ 2011;343:d4464 doi: 10.1136/bmj.d4464

Written by Christian Nordqvist