I vividly remember one scene from The Good Life when Margot is baking a cake and she absent-mindedly picks up a handful of raisins to eat. She just stops short of putting them in her mouth. Barbara is spying on her through the window because Margot has been acting rather strangely. It transpires that she has secretly been going to a slimming club – hence the reason for not eating the raisins, but I use this illustration to show that much of our eating is unconscious behaviour.
Advertising and marketing executives have known for years how various unconscious factors can have a powerful influence on our food choices. One study to be published early next year has looked at whether the order in which we encounter food items influences our estimate of the calorie content. A group of study participants were asked to estimate how many calories there were in a cheeseburger. Interestingly, their answer varied depending on whether they were shown the cheeseburger first or a salad.
The people who saw the cheeseburger first thought it had 570 calories, whereas those who saw the salad first estimated that the cheeseburger had 787 calories—a 38 percent difference. In other words, simply switching the order in which the food items were presented resulted in significant changes in the perceived calorie content.
What this suggests is that the order in which food is presented affects our perception of it. In this instance, when food was presented in the healthy / indulgent order – i.e. salad then cheeseburger – the healthy food item had the effect of making the consumer attribute more calories to the unhealthy food item and more calories overall. Conversely, presenting foods in the indulgent / healthy order, leads to an underestimate of the calorific value of the foods.
Dr David Ashton
7th December 2010