Monetary incentives turned out to have little influence over how much weight participants in one study lost, leading Nicholas Bakalar of the Times to claim that, "Losing weight is so hard you cannot even pay people to do it."
The study divided 2,407 overweight and obese people into three groups: one got $60 if they maintained a 5% weight loss for a year, another paid $100 but got it back if they kept off the 5%, and a third got $20 for staying in the program, regardless of weight loss. Losing weight is hard: the $20 group lost an average of just 1.8 pounds, while the $50 group dropped 1.4, and the $100 people 3.6. And 76.4% of participants dropped out by the end of the year.
The study authors say that people willing to risk $100 were likely motivated to lose weight no matter what, and that in general the monetary incentives were ineffective. But is the sheer difficulty of weight loss the only factor here? Perhaps money just isn't as strong a motivator as other concerns, like health, the social stigma of being overweight, a culture of dieting, et cetera. Perhaps monetary rewards aren't as effective as, say, an exercise program or nutritional counseling. Or perhaps some participants came to feel insulted by being paid to lose weight.
An interesting parallel is a North Carolina program that pays teen girls not to get pregnant. To enroll, the girls must meet requirements including having a sister who got pregnant as a teen. Once in the program, they get $7 deposited in a college fund for every week they don't conceive. The program also teaches about abstinence and contraception. Of 125 girls who have stayed in the program for six months or more, director Hazel Brown says only six have gotten pregnant or dropped out for other reasons.
In both cases, the monetary aspect is kind of strange — especially paying such a small amount to potentially underprivileged teenage girls seems somewhat condescending. It seems possible that the sex education is what really keeps the girls from getting pregnant, and that the money is just an incentive to get them to show up for the program. It makes a certain amount of sense that teenagers, whose decision-making skills aren't necessarily well-formed yet, would be swayed such basic incentives as $7 a week. But for adults, the social pressures against being overweight are already so intense that a little money may not make a difference. And for some, the ability to lose weight and keep it off may have more to do with biological and sociological luck than with motivation. One of the study authors tells the Times that, "there is surely some amount of money that would persuade most people to lose weight." But successful weight loss may be less about "persuasion," and more about learning the right techniques — and being fortunate enough to have these techniques succeed.