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An Easy Trick for Cutting Down on Junk Food Purchases

A new study, published in the Journal of Consumer Research, reveals one way to curtail the purchase of Bavarian Espresso ice cream, Chips Ahoy and Coke, three items which, sad to say, currently occupy space in my kitchen.

What's the trick? Pay with cash, not credit or debit.

Can it really be that easy to eliminate our family's ice cream sandwiches? I spoke to Manoj Thomas, assistant professor of marketing at Cornell and one of the authors on the study, for clarification.

"We found people had a larger proportion of unhealthy food items in their baskets when they paid by either credit card or debit card, compared to when they paid in cash," he says. This happens only with "vice" products, like cheesecake, cookies, and ice cream -- not yogurt, oatmeal or bread. For "healthy" products, he says, people spent the same amount, cash or credit.

I enjoy talking to people like Thomas, academics who study the data from our shoppers' club cards and devise experiments to test our behavior at the supermarket. Insights into how a shopping brain operates can help those of us trying to save money, shrink our waistlines, or both. Here's what Thomas said about the two major takeaways from his study:

"There are two distinct types of purchasing decisions, and most people don't realize that. The way I make a decision to buy a cookie is altogether different than the way I make a decision to buy oatmeal. I'm not aware of it, but in my mind, the process is very different. If I buy oatmeal, I'm thinking, 'What is the price of it, do I have more at home in my pantry, which brand is healthier?' It's very deliberate, and my decision is governed more by my thought process.

"But when I'm buying a cheesecake or ice cream, it's less deliberate, and it's also an interplay of how I feel about that product. I stand there, I think, 'How will I feel eating that cheesecake? Well, should I or should I not?' Sometimes you think less about it and succumb to your feeling. It's in those situations, that if you know you pay in cash, you become less susceptible to impulses. But all purchase decisions are not categorized by the same process."

The second big takeaway, Thomas says, is how prone we are to environmental influences that most times we're not even aware of. "Who would have thought that mode of payment would influence what we buy?" he says. "Things in the environment that change the way we feel can influence what we buy. So if you really want to be a prudent shopper, you should try to have things in your environment that make you think more about your purchases. Go with a list in your hand, shop with people who are responsible, those kinds of things."

The list-in-hand strategy is well documented, but shopping with people who are responsible? Guess that eliminates anyone in my family. I'll be waiting for Thomas's study on what happens in the brain when you're shopping with kids in the cart.

Photo courtesy Flickr user Masha, CC 2.0
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