In the news this week Reuters Health reported that a new study suggested that when menus have calorie counts, they seem to influence diners, especially those who are least health conscious. And if the study stands scrutiny, this could be incredibly encouraging as a step forward in the war on obesity and its associated lifestyle diseases. There have been previous studies that have confirmed the impact of menus that list calories and other nutrition information on diners. This study sheds light on the impact of this information on specific groups of diners.
The study was set up in 2010, and involved students on the campus of Oklahoma State University. Students who frequented ond particular campus eatery were given one of three menus during a two week period. One menu prototype was a typical menu with no calorie information; one menu offered calorie counts for all menu items; one menu used traffic light “signals” to represent calorie information – a green light for "at or below 400 calories," yellow for calorie counts between 401 and 800 calories, and red for calorie counts above 800 calories. Researchers noted that students using the regular menu ordered meals of about 817 calories, on average. Those who ordered off calorie count menus averaged 765 calories per meal. The students ordering off menus with traffic lights ate meals totaling about 696 calories. Those lower calorie counts could add up to pounds lost over months and years, if the choices made by diners remained consistent. And an interesting finding was that the students who were least health conscious seemed to show the most significant changes in their meal choices when exposed to calorie counts and especially traffic signal labels. The researchers did note that the traffic signal approach to menu labeling seemed to have the most significant impact on diners.
A Food Navigator report suggests that many processed foods have calorie counts that could be underestimating actual calorie consumption, by as much as 30%. Many calorie counting systems have not been updated with current science and are therefore providing seriously flawed calorie count information. Calorie counting systems are also not accounting for fiber content impact on calories, and they are not evaluating the calorie count differential between raw and cooked versions of a food. This misinformation can have a huge impact on consumers’ decisions in terms of food choices, food preparation impact on calories, and most importantly on portion sizes. Further complicating food decisions, is the perception of consumers that if a food has fiber, you can eat more of it, since the fiber will “cause you to eliminate more of the food after digestion.” In fact, the fiber can add calories in some cases. The Atwater model from the late 19th century, which has been periodically updated, is still the basis of calorie measures by the food industry and doesn’t account for fiber calories or for that matter “chewing calories” burned, when a food requires extensive desiccation before being swallowed.