People who use big forks eat less compared with diners who use small forks — but only when eating from a plate loaded with food, according to a new study.
Over a period of two days, researchers from the University of Utah in Salt Lake City monitored customers at an Italian restaurant during two lunches and two dinners. With one of the study's authors and two research assistants serving as waiters, the researchers assigned either large forks or small forks to certain tables.
The fork assignments were rotated after every meal, and the ordered plates of food were weighed on a food scale before they were brought to the customers. After the plates were brought back to the kitchen, either empty, with leftovers to be disposed of, or needing to be boxed to take home, they were weighed again.
The findings showed that when the initial quantity of food was more, with a well-loaded plate, diners with small forks ate significantly more than those with large forks. That may be because diners feel they are not eating enough of their food when using the smaller fork and are therefore not satisfying their hunger, according to the researchers.
"The physiological feedback of feeling full or the satiation signal comes with a time lag," the researchers explain in a statement. "In its absence diners focus on the visual cue of whether they are making any dent on the food on their plate to assess goal progress."
When customers were given plates with small servings of food, however, the fork size did not affect the amount of food consumed. This may be because small servings allow diners to better visually gauge how much food they've eaten, while it's harder to tell how much progress has been made when eating from a large serving.
"People do not have clear internal cues about the appropriate quantity to consume," the researchers wrote in the current issue of the Journal of Consumer Research. "They allow external cues, such as fork size, to determine the amount they should consume."