A blog-keeping note: the national spotlight series is by no means over! I am just going to intersperse other posts, like this one, when inspiration strikes.
Recently, I read a study by Oxford’s Department of Experimental Psychology that made me reflect more on how our eating behavior leads to waste. The experiment, published in 1982, tested how variety in the color, texture, and flavor of food in a meal influenced a person’s consumption and enjoyment. Only one of the sensory properties was changed in each round of the experiment while the other two were held constant. For instance, Smarties (a candy similar to M&M’s) were used to test the influence of color because they are uniform in texture and chocolate flavor.
I won’t recap the entire process and detailed findings of the experiment, but the general conclusion was that humans eat more when offered food in varying textures, colors, or flavors. So, if given a plate of only green Smarties, we will eat fewer than if we were given a plate of mixed-color Smarties. This indicates that there is a sensory-specific satiety effect: we stop eating sooner when eating a ‘plain’ meal than when our senses are variously stimulated by a meal, even if there is no difference in the nutrition of the food to influence our actual fullness.
Another conclusion of the experiment was that “the degree of pleasantness of a food may affect whether a food will be selected for ingestion, but the amount actually ingested will then depend to a considerable extent on the satiating power of that particular food.” In other words, knowing that we like a food makes us more likely to choose to eat it but does not necessarily mean that we will eat more of it, especially if it is something filling. This is the part of the report that got me thinking about waste:
Put this effect in the context of a buffet, dining hall, or any other smorgasbord scenario where we are presented with an abundance of options. Many people erroneously start filling their plates or trays before having seen all of the available foods. When they then come across a favorite food of theirs, they add a large portion of that to their meal because they know they are going to enjoy it. They don’t generally think about how much other food they already have; they prioritize the favorite and end up with an extra large portion.
Assuming they recognize their satiety (which is often difficult to do, leading to overeating), the eaters will not finish all of the food that they have taken. Whether the diners scarfed down their favorite food first or tried to save the best for last, some remnants of the superportion will be left. Of course, leftovers can be given to a friend or taken home in a doggy-bag, yet the sad truth of the matter is that many people leave the food to be thrown out. I don’t have any statistics to back it up, but I believe that people are more likely to bring home leftovers from a meal paid for a la carte than in a buffet-type setting because they feel more motivated to get their money’s worth. In restaurants, you think, “I spent $12 on that pizza, so those last three slices are $4!” When you pay a flat rate for a self-serve meal, though, you pay for ‘all you can eat,’ which is achieved once you are full.
It’s no surprise that presenting people with an abundance of food, especially food they know they like, can easily lead to waste. Nor is it shocking to read that our eating behavior is influenced by psychological at least as much as by physiological and nutritional factors. Still, the study makes an interesting read to explain the extent of this influence and reflect on its role in issues like food waste or obesity.