How far would you be willing to go for your favorite afternoon snack? Imagine the vending machine near your office is out of it. What would you do next? Some of us would simply choose another snack or just go back to our desk, but others would walk farther to the next vending machine, and still others would drive to the closest convenience store.  

How motivated you are to obtain food, as measured by effort or work, is called the reinforcing value of food. Those who would work harder to get their snack have higher food reinforcement and are generally heavier, gain more weight over time, and eat more.

But, don’t worry if you are one of those who is willing to put more effort toward your daily snack – new research sheds light on strategies you can use to facilitate eating less.

One strategy takes advantage of the fact that preferences for foods or activities are relative to available choices. Cookies may look pretty good when there are only carrot and celery sticks around, but cookies may not be your preference when ice cream becomes available. In the lab, we can ask children to work for food or activities by clicking a mouse to earn points to see their relative preferences. These points are harder to earn the more portions the child wants, giving us an idea of the highest number of clicks a child feels a food or activity is worth. The first portion is easy, with about 20 clicks, and the later portions eventually increase to 2160 and up. 

Studies in the lab have shown that the types of choices available influences children’s preferences for physical and sedentary activities. When given choices between a well-liked sedentary activity, such as videos and computer games, and a well-liked physical activity, such as a balance board and exercise bike, children chose to work more for the sedentary activity. However, when given choices between a moderately-liked sedentary activity, such as puzzles and magazines, and a well-liked physical activity, children chose to work more for the physical activity. The types of activity choices available can influence your relative preferences.

While previous research has looked at choices between different activities or between different foods, there is less research on choices between foods and activities. Can highly-rated activities be a substitute for eating desirable foods? As simple as it sounds, focusing on how alternative activities can influence motivation for food has had limited research.

In order to investigate whether activities could reduce motivation for food, we conducted an online study with four hypothetical scenarios, in which everyone had a choice between a favorite meal and an activity. People were able to choose their favorite from a list of four categories of activities: enriching sedentary (reading, listening to music), non-enriching sedentary (watching television, playing mobile games), social (attending a social club, having friends visit), and physically active (running, biking). They were then asked how many hypothetical button presses (i.e., work) they would be willing to do for a meal or activity. As they made choices, the work required for the activity stayed at a low number (80 button presses), while the work required for the food increased (40 – 650 button presses). That way, we could see at what point people were willing to expend equal effort to obtain either the food and activity, or in other words, when the food and the activity were of equal reinforcing value. We then compared the highest number of button presses people were willing to make for food when there were different activity options available. We were interested in examining at what point the cost of the favorite food became too high, and people switched to choosing the activity instead.

We found that social activities and enriching activities were the best substitutes for food. People switched to these types of activities soonest as the required effort for food increased. Not surprisingly, physical activity was not a good substitute for favorite foods; people took longer to switch away from a costly meal to these types of activities. Non-enriching activities proved the least appealing when offered instead of food. While people obviously spend a lot of free time watching television and using social media, people often eat during these activities, making them complementary to consumption. Social and enriching activities are better at competing with eating.

It is important to note that these choices were hypothetical, and future work should replicate these findings when people have to actually work for the food and activities they want. But this study does suggest that different categories of activities are more or less able to compete with motivation for food. Changing someone’s eating habits may be easier when you offer fun alternatives instead. Doing the crossword, or listening to an interesting podcast may be a good substitute to a late afternoon candy bar from the vending machine, while watching YouTube videos may not.


Katelyn Carr, PhD. is a post-doctoral fellow at the University at Buffalo. She is interested in how behavioral economics influences choices, with a focus on food and activity choices.