A short communication in the International Journal of Obesity caught my eye this morning. A research group from Cornell explored some seemingly-obvious questions: Do people eat food just because its there, and will they eat more if the food is close in proximity and unlimited in supply? And one not so obvious: Do we underestimate how much we eat when the food is closer (the idle munching effect)? (More below the fold!)
The team recorded the chocolate consuption of 40 adult secretaries for 4 weeks. They manipulated proximity by placing the chocolates on the desk of the participant or 2 meters away, and visibility was manipulated by making the dish either transparent or opaque. The supply of chocolate was unlimited; it was filled every evening.
The results showed that both placement and visibility mattered.

According to their results, the secretaries ate the most chocolates when the bowl was on their desk and clear and ate the least chocolates when the bowl was far and opaque. In addition, there was a significant difference between their ability to estimate how many candies they had eaten when the dish was on their desk, opaque or not. Subjects had a tendancy to overestimate candies eaten when the dish was far, and to underestimate when the dish was near.
“This has important implications for people who are trying to be accurate in monitoring and controlling their intake of food. These results underscore that people need to take a food’s visibility and proximity into account when they try and estimate their prior consumption of it. In general, a food that is less proximate to consume – say cookies in the cupboard vs those on the counter – may be over-consumed relative to what one might think (or recall).”