No, it’s not that second Baconator I ate yesterday or the 6-pack of Schlitz I had afterward that’s causing my clothes not to fit anymore. It’s the credit card I used to pay for them — or at least that what the authors of a new study are theorizing.

According to a new study published in the Journal of Consumer Research, paying with a credit card instead of cash leads to more impulse food purchases, and most impulse food purchases are not of the healthy variety.

From the authors of the study:

Two factors contribute to this intriguing effect. First, there is a correlation between unhealthiness and impulsiveness of food items: Unhealthy food items also tend to elicit impulsive responses. Second, 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 relationship between these trends suggests that self-control is not entirely volitional; it can be facilitated or impeded by seemingly unrelated contextual factors that influence people’s visceral feelings.

After studying the shopping behavior of 1,000 households over a period of six months, the researchers say they found that “shopping carts had a larger proportion of food items rated as impulsive and unhealthy when shoppers used credit or debit cards versus cash.”

Do you find yourself buying more bad-for-you foodstuffs when you’re paying with plastic?

Cash Is Healthier? Credit and Debit Increase Impulsive Food Purchases [PDF via SeattlePI.com]

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