We humans can so easily give in to our vices. Something as simple as a credit card can weaken self-control. The good news is that the reverse is also true: cash can buffer us from indulgence. So says a study in the Journal of Consumer Research.

Scientists analyzed people’s perceptions of various food types and found that foods considered unhealthy were also seen as more likely to be impulse buys. The researchers then followed the grocery shopping habits of 1,000 households over six months. They found that people bought a larger proportion of unhealthy and impulsive food choices (think: jelly doughnuts) when they used their credit or debit card versus cash.

Desire that leads to impulsive behavior is caused by so-called "visceral factors," like the anticipation of the pleasure of eating the doughnut. And so the author's note that desire might be weakened by aversive visceral factors, like pain. Other studies have found that paying with cash was more painful that tossing over the credit card.

So the pain of cash payment seemed to actually control buyers’ impulses. Seems like the craving to eat a Napoleon can be topped by the desire to hold on to your Benjamins.

—Christie Nicholson