Want to help yourself eat healthier? Pay with cash.
And I’m not just making this up, either. A new study by researchers from Cornell University and the State University if New York, published last week in the Journal of Consumer Research, shows that people make fewer impulse purchases—including junk food—when they pay with hard currency rather than plastic.
The secret is that cash carries a high “pain of payment:” people get a stronger negative feeling from forking over paper money than they do from swiping a credit card. And that “pain” is especially high for impulse purchases—like that Snickers bar you sneak in the basket during checkout. (Yes, I saw that!)
You’d think that the form of payment wouldn’t matter—cash is cash, after all, and the money you save on credit card bills means more cash in your pocket later. But people are weird; quite often, we simply don’t behave the way ivory-tower economic theory predicts. Take, for example, the study I wrote about earlier this year on subsidies for healthy food, like fruits and vegetables. You’d think that direct financial incentives would lead people to choose better diets. But many shoppers simply use the money they save on apples to buy more junk food.
But as valuable as the “pain of payment” study is, it irks me that it suggests that consumers themselves are responsible for the obesity epidemic:
“[T]he growing obesity problem and its economic consequences have been attributed to consumers’ failures to control impulsive urges (Ubel 2009).”
So obesity is mostly a matter of personal “failure,” huh? To, me that’s a stretch. After all, human beings evolved in a harsh environment in which sweets, fats, and starches were incredibly rare—and where gorging on easy calories was a great survival strategy. Genetically, we’re terrible at exercising restraint around food. And to make matters worse, we’ve created a food system that pumps out incredible amounts of inexpensive sweets, oils, and starches; packages them in cheap and tasty ways; and spends billions on sophisticated marketing techniques to get us to open our wallets to buy them. The “failure” isn’t a matter of personal will, but of a food system that exploits tendencies that are hardwired into human nature.
So if we want people to eat more healthfully, we have to look beyond scolding them for being human. We need food prices to reflect the true costs of sugary sweets and trans-fat laden snacks. And we need proper education about how to cook and eat well. These require systemic changes, not nagging about a lack of willpower. Suggesting that we switch to a cash-only diet at the grocery store might help a bit, by exploiting one human foible to counteract another. But thinking that it’s enough to fix bad eating habits is just, well, nuts.