Overeating clearly plays a major role in the obesity epidemics many developed countries find themselves in. Increasingly, studies are showing that overeating is not the result of an excessive appetite or constant hunger, but rather psychological aspects that many companies know to take advantage of. A recent study published in the Journal of the Association for Consumer Research has found that all too many people associate foods that are labeled as “healthy” with “less filling.” Unfortunately, this leads to them to eat more than the recommended serving size.

Researchers conducted a series of three studies aimed toward investigating the “healthy equals less filling” intuition. In the first study they used the Implicit Association Test to examine the relationship between the concepts of healthy and filling among 50 undergraduate students from a large public university. In the second study they recruited 40 graduate students and gauged their hunger levels after eating a cookie that was either deemed health or unhealthy. And in the third study they recruited 72 undergraduate students who were put in a real-life scenario comparing the amount of food ordered before watching a short film to the actual amount of food consumed during the film.

Results showed describing food as healthy was more impactful on consumer judgement and behavior when compared to calling it unhealthy and putting a nutritional scale on the front of the package. Students who were told food was healthy reported lower hunger levels after consumption; however, they also ordered and consumed bigger portions of food compared to student who were told the food was unhealthy. This even occurred among consumers who said they disagreed with the notion that healthy foods are less filling than unhealthy foods.

A number of recent studies have scrutinized the practice of using health buzzwords, like “organic,” “whole grain,” and “antioxidant,” saying these words only trick people into thinking only certain foods are healthy, when they're not actually any healthier. Researchers from the University of Houston recently found these health buzzwords often trick consumers into thinking a certain company’s product contains more nutrients than it actually does. As a result, consumers are lured into a “false sense of health” when they’re actually just overeating.

One of those health buzzwords — “gluten-free” — is obviously used to indicate which foods are safe for people with celiac disease or a wheat sensitivity. But it also lures consumers without a wheat sensitivity into thinking these types of food are healthier for them. In reality they are depriving themselves of essential nutrients found in wheat products. There is a simple answer to this labeling confusion, however: “highlighting the nourishing aspects of healthy food mitigates the belief that it is less filling,” the researchers said. While this does seem like an obvious fix for both consumers and health officials, food companies might rather make money.

Source: Van Ittersum K, Wansink B, et al. The Behavioral Science of Eating. Journal of the Association for Consumer Research. 2015.