Researchers at the State University of New York analyzed the shopping habits of 1,000 households over a six-month period to examine the factors influencing buyer behavior. Specifically, they set out to determine whether the mode of payment affects consumers' ability to control their impulsive urges. The shoppers alternated between using credit and cash at the supermarket.
Paying in cash increases what's known as the "pain of payment," and curbs the desire to buy junk food like cookies, cakes and pies, the researchers found. "The pain of paying in cash can curb impulsive urges to purchase such unhealthy food products," the authors conclude. "Credit card payments, in contrast, are relatively painless and weaken impulse control."
The authors note that the number of obese Americans has increased substantially in the past two decades, while credit cards have replaced cash as the preferred form of payment during the same time period.
One more dieting tip can be culled from the research: People who did their shopping on weekends were less likely to purchase unhealthy food items, ostensibly because they used prepared shopping lists.