by Nicole Witham
Randomized trials demonstrate that incentivizing weight loss leads to more pounds lost than trying to lose weight without money on the line, at least in the short-term. Insights from behavioral economics, the study of how psychology and sociology influence our economic decisions, offer explanations as to why weight loss bets are successful. Most importantly, people hate to lose what they already have – in the case of a weight loss bet, their own money. This is called loss aversion. The desire to hold on to hard-earned cash rivals another concept behavioral economists study, immediate gratification (or future discounting). People are inclined to value immediate rewards higher than delayed gratification. Immediate gratification leads individuals to consume highly palatable, energy-dense foods, rather than choosing the more nutritious but perhaps less tasty options that will lead to better future health.
These two inherent traits are at odds with one another in a weight loss bet. Successful betting relies on the fact that the player fears losing his or her money more than he or she wants to eat unhealthy foods or skip exercising (meaning I would have to challenge my natural cookie-buying inclinations if I participated in a weight loss bet).
While the motivation to save, or even make money, leads to weight loss in the short-term, the ability of players to keep weight off in the long-term is limited. Skeptics of weight loss betting, or any fad weight loss program in general, propose that sustained weight loss requires lifelong behavioral modifications that a short-term bet might inspire but cannot ultimately guarantee. Additionally, public health professionals emphasize that weight loss bets may work on an individual-level for some people, but attention and policies need to be directed largely at fixing the environment that promotes obesity to inspire change on a population-level. To win big, we need to find the special sauce that turns the short-term success of weight loss betting into a long-lasting payoff.