A Behavioral Scientist’s Tips For Not Gaining Weight or Over-Eating This Holiday Season

With the holiday season quickly approaching, food is the centerpiece of most social gatherings. We love our holiday feasts, but this causes an annual pattern of extended binge eating that, for most Americans, is kicked off by Thanksgiving and doesn’t end until after the New Year. Based on Google searches, health was one of the top two New Year’s resolutions. However, only around 9% actually report feeling successful in achieving their resolutions.

We interviewed experts at the 2017 Society for Judgment and Decision Making (SJDM) conference to learn more about why this happens, and what we can do about it.

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We Don’t Realize How Much Food We Eat in Exceptional Contexts

Dr. Abigail B. Sussman and Dr. Anna Paley presented research, co-authored with Adam Alter, showing that when we are eating “exceptional foods” defined as foods consumed less frequently, we tend to eat more within that meal. If this meal is at lunch, there is also less compensation for these extra calories at dinner. This lack of mental accounting also transfers to exceptional contexts; in our interview with the researchers, Dr. Anna Paley, explained that…

“In the first two studies we looked at, we kept the food items the same and just manipulated the context in which they were served in. These studies show that people think about the exact same foods very differently… and when these foods were accounted [for] in more exceptional contexts, people felt that they needed to work out less to compensate for the foods that they ate; and that these foods have less of an impact on their diet.”

On special occasions that happen infrequently, many of us dangerously exclude the foods we eat from our normal calorie accounting. After all, you only get to eat grandma’s cooking once a year. Studies have shown that our mental accounting simply skips the foods we eat in exceptional locations as well as if the food itself is different.

What Can We Do to Avoid This?

We also interviewed Dr. Romain Cadario who presented a new meta-analysis on 78 field experiments to identify the most effective behavioral interventions for healthy eating.

Six controlled studies in restaurant settings showed that calorie labels had no significant effects on total calorie reduction. Although nutritional labels are not effective, there are a few other things you can try.

Serve Smaller Portions

Many studies included in Dr. Cadario’s meta-analysis show that people consistently consume less food when portion or plate are smaller in size. Smaller portions in diners, restaurants, and school cafeterias all decreased overall consumption of foods. In a cafeteria-style restaurant, customers who were served smaller entrée portions consumed 43% less energy compared to the larger plate entrée portion. Additionally, there was no difference in customer’s perceptions of food consumed. The customers who received smaller portions perceived their portions as an equally appropriate size as the larger portion customers.

Dr Cadario told us that you may easily practice some of these nudges at home. For dinner, eat a smaller, pre-portioned plate of food, wait a few minutes, and eat a yogurt or salad if you are still hungry after finishing your plate. With candy, put a handful into a small bowl to bring to your room instead of the entire bag. This will decrease the convenience and accessibility to more candy and the likelihood of mindlessly eating the entire bag.

At your next holiday celebration, serve yourself and others smaller portions; you may not even perceive a difference in the amount of food you’re eating.

Serve the Mashed Potatoes in a Smaller Bowl and Serve the Brussels Sprouts in a Larger Bowl

In a movie theatre, moviegoers with smaller popcorn containers ate 45.3% less popcorn than those with larger popcorn containers. Compared to the smaller popcorn containers, the moviegoers with larger popcorn containers ate more even when their popcorn was stale.

In contrast, larger plate sizes can be utilized to help promote healthy eating when used for nutritious foods. When children were given adult size plates and bowls with a 100% increase in surface area compared to child-dishware, they served themselves 15.7 more calories of fruit.

Tableware and pre-portioned sizes act as a visual anchor that we identify as a consumption norm used to decide how much to eat. Size of tableware consistently dictates individual’s consumption quantity, often without any fluctuations in both the individual’s perceived consumption amount or perceived deviation from their typical consumption. Next holiday meal, try using smaller tableware to decrease the amount you eat.

Arrange Your Table so That Healthier Options Are Easier to Reach

Research in elementary school cafeterias revealed that simply serving students vegetables while they waited in line for the rest of their lunch increased the total amount of vegetables consumed.

From the wise words of Dr. Cadario:

“Maybe being health literate is not enough, perhaps it’s about how you can be more behavioral economics literate.”

This holiday season, instead of relying on your self-control the moment the homemade casserole comes out of the oven, serve yourself smaller portions, downsize the tableware for unhealthy foods, and make sure the healthy foods are more easily accessible to help decrease the amount of food you eat.

Stay tuned to learn more! The Better Living and Health group is digging into how to help you live a healthier life.

Michelle Zong is an associate at the Center for Advanced Hindsight. She holds a Bachelor of Science degree in psychology and economics from the University of North Carolina – Chapel Hill. Michelle can be reached at michelle.zong@duke.edu.

Rachel Kahn is a research associate at the Center for Advanced Hindsight. She holds a Bachelor of Science degree in biomedical engineering from Washington University in St. Louis. Rachel can be reached at rachel.m.kahn@duke.edu.