Research in the mann Lab


Self Control of Health Behaviors: An Introduction

The work in the Mann Lab focuses on self-control of health behaviors with an emphasis on eating behaviors in particular.

Our studies take on two different forms. First, we aim to understand the various factors that make it difficult for people (especially dieters) to control their eating. We are interested in aspects of the individuals themselves, but we are even more interested in aspects of the situations that individuals are in, including those that seem trivial (e.g., distracting situations) and those that do not (e.g., friends eating).

Second, we aim to understand the factors that promote eating so that we can improve the health of two very different populations: children and astronauts. We are using various nudges, or tiny changes in eating, to encourage vegetable consumption in elementary school children and to prevent inadvertent weight loss among astronauts on long missions.

Attention & Self-Control: Funded by National Institutes of Health

This work is an ongoing collaboration with Andrew Ward (Department of Psychology, Swarthmore College). NIH has funded this work for ten years (2002-2007 from the National Institute of Mental Health; 2008-2013 from the National Heart, Lung, and Blood Institute).

In this work, we are looking at the factors that cause dieters to overeat, and in particular, on how attention both causes overeating and prevents it, depending on the circumstances. It is commonly thought that when people are unable to focus their attention on their goals and behavior, they are likely to lose control – to act in ways that they do not intend or desire. Our research shows that instead of leading to a loss of control, lack of attention simply increases the extent to which people’s behavior is influenced by the most noticeable features of their environment. In cases where the environment contains highly salient reminders of one’s goals (e.g., a scale as a reminder of a diet), individuals who are distracted may control their behaviors better (e.g., eat less) than if they were not distracted. In addition, we have found that there is a certain amount of distraction that helps people control themselves better, even without salient diet reminders present. We explore these same processes in people trying to quit smoking as well.

Increasing Vegetable Consumption in Children: Funded by USDA and the Cornell B.E.N. Center

This work is a collaboration with UMN faculty Marla Reicks (Nutrition), Elton Mykerezi (Applied Economics), Joe Redden (Marketing), and Zata Vickers (Food Sciences). We are working primarily with Deb LaBounty of the Richfield, MN school district. Graduate students Heather Scherschel, Rachel Burns, and Katie Osdoba are working with us on these projects.

In our work funded by the USDA and the Cornell Behavioral Economics and Nutrition Center (B.E.N. Center) we are testing a variety of ways to get kids in school cafeterias to eat vegetables. This work is based on the idea that using nudges, or small changes to one’s surroundings, can have larger effects on behavior than efforts to persuade people to change.

Our first nudge was simply placing pictures of vegetables in the compartments of cafeteria trays. This tripled the amount of vegetables elementary school students ate, probably by giving them the sense that everyone else must put vegetables in those sections of the trays and then eat them. Our second nudge was serving carrots to students before they went through the cafeteria line. This also tripled the amount of carrots the students ate, likely by keeping the vegetable from having to compete with the yummier, less healthy foods that they will get in the cafeteria later. We are testing this in a longer-term study to see if these effects last. Finally, we are testing nudges within people's homes, where they have yet to be explored closely.

Preventing Weight Loss in Astronauts: Funded by NASA

We are excited to be contributing our tiny part to NASA’s research planning for eventual manned missions to Mars. This work is a collaboration with UMN faculty Joe Redden (Marketing) and Zata Vickers (Food Sciences). Graduate students Heather Scherschel, Rachel Burns, and Katie Osdoba are working with us on these projects, along with Britt Ahlstrom.

Before NASA can send astronauts to Mars, they must solve hundreds (probably thousands) of different problems that complicate such a monumental task. One very small problem that NASA needs solved is how to prevent astronauts from losing weight on long missions. When astronauts go on missions to the International Space Station, they tend to under-eat and lose weight. Mars missions will be many times longer than missions to the ISS, and this weight loss could therefore be a problem. We are attacking this undereating in three ways. First, we are trying to prevent astronauts from getting sick of the somewhat limited (but not as limited as you might think!) space diet. We are using an intervention that Joe Redden found effective in keeping people from getting sick of songs and from getting sick of jellybeans. Second, we are testing whether giving astronauts control of their meals and the opportunity to use creativity in meal preparation might reduce their levels of stress, because the stress of space travel is thought to be oe reason astronauts under-eat. Related to that point, in our third study for NASA, we are testing the effectiveness of comfort foods in improving astronauts' moods.

Food Labels and Food Choice

Heather Scherschel, Maryhope Howland, and I have been looking at the effects of different types of food labels on whether people select the food. The FDA (which is not a funder of this work) is interested in putting different kinds of health information on the front of food packages, in addition to the nutrition information box that is already on the back). We are looking at what happens when we put the word “Healthy” on a sign for apples* or carrots. We find that pretty much anything we say on these signs is more likely to get people to take the apples or carrots than calling the food healthy. Using the symbol for heart healthy also works better than the word healthy. We’re testing out some reasons why this is the case.