THURSDAY, Oct. 21 (HealthDay News) -- People are less likely to buy unhealthy foods if they use cash instead of credit or debit cards to pay for groceries, a new study finds.

U.S. researchers analyzed the shopping behavior of 1,000 households over six months and found that the participants' shopping carts contained a larger proportion of impulsive or unhealthy food products when they paid with credit or debit cards rather than cash.

Further research revealed that "cash payments are psychologically more painful than card payments, and this pain of payment can curb the impulsive responses to buy unhealthy food items," the authors reported in their study, published online and in an upcoming print issue of the Journal of Consumer Research.

"The notion that mode of payment can curb impulsive purchase of unhealthy food products is substantially important. The epidemic increase in obesity suggests that regulating impulsive purchases and consumption of unhealthy food products is a steep challenge for many consumers," according to the researchers from Cornell University and the State University of New York in Binghamton and Buffalo.

If people understood that they're more likely to buy unhealthy foods when paying with credit or debit cards, they might be able to control their buying habits, the study authors suggested.

The authors, Manoj Thomas, Kalpesh Kaushik Desai and Satheeshkumar Seenivasan, also indicated that there is a possible link between rising obesity rates in the United States and changing modes of payment. They noted that credit or debit cards were used for nearly 40 percent of all purchases in 2006.

More information

The American Academy of Family Physicians offers advice about healthy eating.