You may have heard of the grapefruit diet, the Beverly Hills diet or even the cabbage soup diet, but the latest contribution to the weight-loss armoury may take you by surprise.
It has been developed by two business school professors and is whimsically referred to as the “economists’ diet” by co-inventor David Crowson, assistant professor in the strategy and entrepreneurship department at the Cox school at Southern Methodist University, in Dallas, Texas.
An economist, Prof Crowson has been working with marketing professor Suzanne Shu, a psychologist by training and an expert on willpower, to devise a regimen that has a higher chance of success than the usual new year crash scheme. “Compared to some of the crazy diets out there, ours is positively scientific,” Prof Crowson says.
Unlike most diets, the economists’ regimen is based on more than just counting calories, reducing fat intake or eating specific food combinations, according to Prof Crowson. “It’s not just what you eat but how you spend your time and your money.”
One example might be that, if the dieter comes home tired from work and opens the refrigerator and finds a salad there (which he or she has prepared that morning), he or she is more likely to eat the salad than order a pizza. So getting up five minutes earlier to prepare that evening’s supper, might increase the chances of successfully completing the diet.
So, too, if the dieter saves more of his or her salary, there will be fewer funds for eating out or partying.
The two professors have developed a model that, in true economist’s language, relies on would-be dieters making contracts with their future selves and developing the appropriate incentives at the start of the process.
So, says Prof Crowson, a pizza lover might make a contract with himself that allows a pizza after eating 13 consecutive days of salad. This “austerity and splurge” pattern of dieting is more successful in the long term than trying to eat salad all the time, the professors say.
Prof Crowson has a second piece of advice for those who are still considering their new year’s resolutions: make more rather than less.
Although intuitively it may seem that the more resolutions you adopt, the less likely you are to succeed in any of them, statistically the opposite is true, he says. The more resolutions you adopt, the higher the number of chances there are of failure but the chances of success improve too.
He points to a 1998 study by University of Washington psychologists Alan Marlatt and Elizabeth Miller. This reported that only 37 per cent of people manage to keep their new year resolutions until the end of February. According to Prof Crowson, if you adopt five new year resolutions, the odds of success in at least one of them are nine to one in your favour. “We’re trying to stack the deck in your favour rather than against you,” he says.
Where is the economists’ diet likely to be published? The authors are not aiming for Cosmopolitan or Vogue or even the local library. Their paper has been submitted to the snappily titled Journal of Economic Behavior and Organization.