Variety: Spice of life or risk factor for overeating?
Penn State
image:
a diner fills their plate in the virtual reality buffet
view moreCredit: Travis Masterson and John Long
UNIVERSITY PARK, Pa. — At Super Bowl parties, weddings, Independence Day cookouts and Thanksgiving dinners, people celebrate with large spreads of food. When faced with many options, extra food variety increases people’s selection of foods, especially calorie-rich foods, which may lead to overeating, according to a new study conducted by researchers in the Penn State Department of Nutritional Sciences.
“This study examined what drives people to overconsume food at a buffet similar to dining halls, where millions of college students eat every day,” said John Long, first author of the study and postdoctoral scholar in food science and nutritional sciences. “If we identify the aspects of our modern food environment — excessive variety, slick packaging, processed foods and more — that increase how much people eat, we can redesign our environment to help us make healthier food choices.”
Prior studies at Penn State and elsewhere indicated when people eat from a plate with many different foods, they will consume more calories. The current study, published in the journal Appetite, demonstrated that greater food variety affected how much food people served themselves before taking their first bite. The researchers found that the presence of a higher variety of foods in a buffet increased both the weight of food selected and the number of calories people put on their plates.
How a VR buffet works
The researchers recruited 50 people between the ages of 18 and 65 to visit their laboratory for three sessions, one week apart, all scheduled at either lunch or dinner. During those sessions, participants selected a meal they wanted to consume from a virtual-reality (VR) buffet.
The buffet presented participants with a different number of food items at each visit — either nine, 18 or 27 choices. The buffet included a similar proportion of high-energy-dense foods — like cookies — and low-energy-dense foods — like vegetables — regardless of the number of food options available. Participants were instructed to abstain from exercise, food and caffeine for several hours prior to the visit to make sure they were hungry.
Participants wore a VR headset and entered a VR buffet restaurant where they were able to select foods as they would at an actual buffet using videogame-style controllers in each hand. The system recorded the weight and calories of the selected meal along with the quantity of foods, including high-energy-density and low-energy-density foods.
Prior research by Long and Travis Masterson, assistant professor of nutritional science at Penn State and senior author of the study, demonstrated that people at a VR buffet select similar food to what they would at a real buffet. Knowing that the buffets provide meaningful data, Masterson said using a VR buffet helps save money and time, leading to more efficient research.
“It is costly and wasteful to make an entire buffet so that a single participant can use it at mealtime, especially if that participant needs to go through the buffet multiple times, like in this study,” Masterson said. “And when we need a different setup, it is much easier to change a setting in VR than it is to alter the amount of food on a buffet.”
Variety affects eating behavior
Participants who visited the buffet with nine food items selected just over 600 grams of food. People at the buffet with either 18 or 27 food items selected more than 900 grams of food. Although people took more food when variety increased, there appeared to be a general upper limit to the total weight of food people selected, according to Long, who earned his doctorate from Penn State in 2025.
“External factors clearly influence what and how much people eat,” Long said. “But there seems to be a ceiling to the total weight of food selected for a meal, even as variety increases.”
Despite the upper limit of food weight that people served themselves, the calories selected did not follow the same pattern. Participants who visited the buffet with nine food items selected an average of 850 calories of food. That rose to 1,320 calories — roughly 55% more — when 18 foods were offered, and to nearly 1,500 calories when 27 foods were available. That amounts to a 75% increase compared with what the same participants took from the nine-item buffet.
“When presented with more options, people became more likely to choose higher calorie-dense foods,” Long said. “In the U.S., many people consume more calories than they need, and the wide variety of foods in our environment may nudge us to eat more than we otherwise would.
Preventing overeating
The researchers surveyed participants about their personalities and other factors that could affect food selection. These surveys included a person’s tendency to seek out food variety, whether a person engaged in emotional eating, and their reluctance to try new foods.
Of the five major personality traits in this study — openness, extraversion, agreeableness, neuroticism and conscientiousness — only conscientiousness made a difference. People who scored higher in conscientiousness— a trait linked with self-discipline and goal-directed behavior — were less responsive to the greater variety of foods. When more options were available, they added fewer calories by limiting their selection of energy-dense foods compared to participants lower in conscientiousness.
“We can all be a little more conscientious about our food choices and conscious of our environment,” Masterson said. “Behavior change starts with being aware of the things that influence us. If we are aware that variety might tempt us to eat more than is healthy, we may be able to make better decisions for our health.”
Redesigning the eating environment
In the long run, Masterson and Long said they hope this research will go beyond promoting awareness and help us redesign the ways we encounter food in the world around us.
“Experts have been warning people for decades to watch what they eat, and the obesity epidemic has only increased,” Masterson said. “Clearly, our food environment is overriding our ability to limit our diets.”
Long agreed, and repeated that the eventual goal of this work is improving the food environment for everyone.
“By understanding the factors that drive our choices, we hope to be able to design eating environments that support health rather than overconsumption,” he said.
Other Penn State researchers who contributed to this study include Kathleen Keller, Helen A. Guthrie Chair and professor of nutritional sciences; and Barbara Rolls, distinguished professor of nutritional sciences also contributed to this research. Paige Cunningham, assistant professor of nutritional sciences at Cornell and former postdoctoral researcher at Penn State, also contributed to this research.
Journal
Appetite
Method of Research
Experimental study
Subject of Research
People
Article Title
Food variety affects food selection and variety-seeking behaviors in an immersive virtual reality food buffet
