In the United States, 60 million adults are obese and 9 million children and teens ages 6 to 19 are overweight. Being too heavy increases the risk of health conditions and diseases such as breast and colon cancer, coronary heart disease, diabetes, and stroke. In short, obesity is the #2 cause of preventable death in the United States, which means that identifying effective treatments is both a clinical challenge and a public health priority. But what's the best way to get people to lose weight? Clearly fad diets are not working.
New research indicates that bolstering people's sense of well-being may be a start in promoting healthful weight loss, and that monetary incentives can motivate people to slim down or adopt healthier habits, at least in the short run. Such findings were shared at "The Science of Getting People to Do Good" briefing, sponsored by the Center for Social Innovation of Stanford GSB on March 30.
One study of college-age women who were dissatisfied with their weight focused on the insight that maintaining a healthy body mass index (BMI) requires the ability to cope with stress, which saps mental resources needed to maintain the self-control needed to avoid overeating. The researchers listed concepts typically of value to people (such as close relationships and music) and asked participants to write about one. Members of one group were asked to write about a concept of personal value to them, while members of another group were asked to write about something that was not important to them but might be to someone else.
"Writing about important values bolsters people's sense of personal integrity and well-being," explained Geoffrey Cohen, a professor of organizational behavior in education, psychology, and business at Stanford, who coauthored the study with Christine Logel of the Renison University College. "We wanted to test if it would buffer women when it came to their eating habits."
Sure enough, women who wrote about things that were important to them tended toward eating less of the tempting but unhealthful foods that were offered in the lab after the exercise than those who did not. After 2.5 months, they also weighed less, had lower BMIs, and had smaller waistlines than the other participants. The difference in the groups applied to both those with normal weight and those who were overweight.
"These results provide the first evidence that affirming something you find important can be psychologically fortifying enough to reduce physical health risks," Cohen said.
Researchers also found that participants who had done the values affirmation exercise did better on a measure designed to test their working memory. The task required participants to remember a particular number across time and through multiple activities. "Working memory is akin to the mind's blackboard — a storage system that allows people to hold onto goal-relevant information in the face of distraction," Cohen said. "It's a critical component of self-control." This finding suggests that connecting with what was most important freed up people's energy and attention for other things.
Your Money or Your Life?
In another study of mostly men 30 years or older, researchers gave participants the goal of losing 16 pounds in 16 weeks. Participants were assigned to three groups —— a control group in which they were left to their own devices, a second group in which people could become eligible to win money in a lottery if they hit certain weight goals, and a third group in which they made monetary deposits they would lose if they failed to achieve their goals. A vast amount of research indicates that people regret losses more than they value similar-size gains, which is why the researchers had participants in one group deposit money they would lose if they did not lose the weight. People in all three groups called in their weight daily and reported for weighing at the end of each month.
After four months, the two incentivized groups lost significantly more weight than the control group. The lottery group lost an average of 13 pounds and the deposit-contract group lost an average of 14 pounds. About half of those in both incentive groups met the 16-pound target weight loss, whereas only about 10.5% of the control group did. "The incentive schemes that were designed to leverage behavioral economic principles produced significant weight loss during the 16 weeks of intervention, but it was not fully sustained afterward," said Leslie John of the Harvard Business School, who coauthored the report along with Kevin Volpp of the University of Pennsylvania, George Loewenstein of Carnegie Mellon University, and several others.
Walk While You Work
Turning to exercise as a means of reducing weight, John spoke of another study where she and coauthor Michael Norton of Harvard Business School encouraged sedentary call-center personnel to use walking machines three hours a week for six months while on the job. Participants received weekly emails summarizing their walk station usage. Some received information only on their own performance while others received information on their own plus that of one or more peers.
Over time, usage of the machines by those informed of others' performance went down in comparison to the solo walkers. "Middling performers get dragged down to the level of the lowest ones if they see others are not using the equipment," explained John. A better tack to motivate exercise, she suggested, might be to announce the performance of only the highest flyers.
Companies are now getting on the bandwagon of providing financial incentives to employees for adopting healthier behavior, but, said John, "the devil is in the details of how such plans are implemented." She cited, for example, health insurance companies that are now experimenting with offering benefits for those who enroll in health clubs. But such programs become unwieldy because they require a lot of paperwork. Making these kinds of incentives work is going to take some further refinement, she said.
By featuring this work in a public forum, the Stanford briefing exposed leaders of nonprofits and corporations to cutting-edge research that is encouraging people to behave in ways that benefit themselves, their peers, or their communities. Other studies looked at how to close the achievement gap in schools with just simple self-esteem building interventions, how to encourage people to vote, and how to get people to recycle and promote peace and reconciliation.