Imagine this scenario: You’re strolling through your local grocery store. You pick up a necessary box of pasta, round the corner and suddenly face The Snack Aisle: two shelves filled with endless boxes of sugary and salty crackers, cookies, pretzels and chips. “I sure would love a case of chewy chocolate chip cookies,” you think to yourself. But do you give in to your impulse and take the bait? The answer lies in your wallet.

Turns out the question “Paper or plastic?” applies to more than what kind of bag you use to tote your groceries. Scientists found that when it comes to paying for food, cash may be better for your diet… and your wallet. Buying junk food, like cookies, is considered impulsive and can cause even the most careful coupon-clippers to exceed their budget.

Analyzing the shopping carts of one thousand households over a six-month period, researchers discovered a correlation between junk food buys and paying with a credit or debit card. Plastic-payers bought a higher proportion of foods considered unhealthy and impulsive.

Shoppers paying with cash, however, bought healthier options. There’s something about holding your budget in your hand that limits lavish spending and eating.

But why? The psychological “pain” of payment can in fact reduce one’s grocery bill. The effect is even higher in tight-fisted types who frequently find difficulty parting with their hard-earned money.

Considering forty percent of all purchases in 2006 were made with a credit or debit card… and that over a third of American adults are obese… this information is certainly something to chew on.

So before your next grocery trip, think about making a stop at the A-T-M first. Your health and your budget could benefit.