5 Weight Loss Tips From Behavioral Economists
Behavioral economists study what motivates people to buy, save, donate, and any other number of actions that build society. The following studies reveal proven methods of encouraging healthy eating and exercise.
Business scholars increasingly hinge their hypotheses on sociological and psychological studies, seeking a true handle on what motivates executives, employees, consumers, and policymakers.
For instance, the following studies suggest several simple weight-loss tips.
TIP #1 - Order your groceries a week in advance of delivery. Looking to determine how personal decisions made for tomorrow differ from decisions made for several days from now, researchers from Harvard Business School and the Analyst Institute evaluated a year's worth of customer orders from an online grocer. Specifically, they wanted to find out whether a delay between order completion and order delivery would have an effect on which items the customers chose to buy. In other words, would a customer be more likely to choose kale over Kit-Kats if he ordered his groceries a week in advance rather than a day in advance?
Indeed, the data showed that customers tended to order a higher percentage of "should" items (like leafy greens) and a lower percentage of "want" items (like candy bars) the further in advance they placed an order.
For a detailed account of the study, see "I'll Have the Ice Cream Soon and the Vegetables Later: Decreasing Impatience over Time in Online Grocery Orders" by Todd Rogers, Katherine L. Milkman, and Max H. Bazerman.
TIP #2 - Put your money where your mouth is. Leslie John, now an assistant professor at HBS, led an experiment at Carnegie Mellon in which subjects essentially went double-or-nothing on a diet bet. A group of obese hospital patients agreed to a "deposit contract," banking a small amount of their own money into a pot each day during a 32-week weight-loss trial. The research team agreed to match the deposits dollar-for-dollar; the patients were allowed to deposit up to $3 per day.
If participants reached their weight loss goal by the end of the trial, they got to keep the money, thus doubling their deposits. But if they failed to reach the goal, they lost all the cash. Meanwhile, a control group of participants entered a weight loss program with no financial incentives.
The researchers found that the financial incentive group lost significantly more weight in 32 weeks than did the control group. (Unfortunately, much of the weight came back after the eight-month trial was over.)
For a detailed account of the experiment, read "Financial Incentives for Extended Weight Loss: A Randomized, Controlled Trial," published in the June 2011 edition of Journal of General Internal Medicine.
TIP #3- Fill your backpack with rocks. A research team from Harvard and the University of Central Florida tested the theory that the physical feeling of weight is associated with the emotional feeling of guilt.
The researchers asked 67 college undergraduates to complete a series of tasks that involved recalling past guilt-inducing behavior, confronting an opportunity to cheat, and choosing whether to eat a piece of chocolate or an organic fruit strip. The catch: half the students went through the experimental session wearing 15-pound backpacks, while the other half wore 5-pound backpacks.
The results showed that participants wearing a heavy backpack indeed experienced higher levels of guilt than the light backpack wearers. More importantly, the backpacks affected behavior. Those wearing a heavy backpack were more likely to choose healthy snacks over potentially guilt-inducing fattening ones.
For a detailed account of the experiment, see "The Burden of Guilt: Heavy Backpacks, Light Snacks, and Enhanced Morality" by Harvard Business School Associate Professor Francesca Gino, Maryam Kouchaki (Harvard's Edmond J. Safra Center for Ethics), and Ata Jami (the University of Central Florida). The article will be published in an upcoming issue of Journal of Experimental Psychology.
TIP #4 - Put your hands on your hips a la Wonder Woman. Harvard Business School Associate Professor Amy Cuddy joined researchers from Columbia University to test how body language affects body chemistry. Specifically, they wanted to suss out the beneficial effects of so-called "power poses"—adopting various stances that make people look confident even if they're not feeling confident. The results were striking.
Writer Julia Hanna described the experiment in a previous HBS Working Knowledge article:
"Cuddy and coauthors Dana R. Carney and Andy J. Yap of Columbia University detail the results of an experiment in which forty-two male and female participants were randomly assigned to a high- or low-power pose group. No one was told what the study was about; instead, each participant believed it was related to the placement of ECG electrodes above and below his or her heart.
Subjects in the high-power group were manipulated into two expansive poses for one minute each: first, the classic feet on desk, hands behind head; then, standing and leaning on one's hands over a desk. Those in the low-power group were posed for the time period in two restrictive poses: sitting in a chair with arms held close and hands folded, and standing with arms and legs crossed tightly. Saliva samples taken before and after the posing measured testosterone and cortisol levels."
Medical studies suggest that a high level of cortisol, known as "the stress hormone," leads to an excess of abdominal fat. That means lowering cortisol levels is good for your waistline. Sure enough, Cuddy and her team found that high-power poses increased testosterone levels by about 19 percent and decreased cortisol levels by some 25 percent, for both men and women. (Low-power poses, on the other hand, decreased testosterone and increased cortisol levels.)
TIP #5 - Ignore your lazy colleagues. HBS professors Leslie John and Michael Norton conducted field research in which office employees at a large corporation had the option to work at walkstations—standing desks attached to slow-moving treadmills. The researchers kept track of how many minutes each employee spent walking on the treadmill each week.
The goal of the experiment was to test whether knowing about our peers' health behavior has a direct effect on our own health behavior. In other words, are we more or less likely to go to the gym every day if we know whether our friends are going?
To that end, the researchers assigned the participants to one of three conditions. Some had access only to data about their own treadmill usage (the solo condition); some had additional access to the usage of one coworker (the duo condition); and some had access to the usage of four coworkers (the quintet condition).
On average, the results showed that those in the solo condition spent more time on their walkstations during the six-month period than those in the duo or quintet conditions. The reason: When it comes to exercise, people tend to match their activity to the lowest common denominator. All else being equal, we're less likely to aspire to the athletic prowess of the marathon-running cubicle mate than to align ourselves with a sedentary doughnut lover. "People's activity levels tended to converge to the lowest-performing members of their groups," the researchers write. "In summary, our results suggest that the mere provision of information on peer health behaviors can have perverse effects on one's health behavior."
Their paper "Converging to the Lowest Common Denominator in Physical Health" will be published later this year.