Bringing your own bags to the supermarket? According to a new study, that's probably not as good for your diet as it is for the environment.
The study, which was conducted by researchers from Harvard Business School and Duke University's Fuqua School of Business, found that people buy more organic food when they grocery shop with reusable bags -- but also more junk food.
Researchers analyzed data from two different groups: The first was made up of loyalty cardholders at a grocery store in California, none of whom were instructed about which bags to use. They shopped as usual. A second group was made up of online recruits who participated in an online simulation in which they were assigned to either bring their own bags or use the "store" bags. Then, they were told to list the top ten items they would purchase based on a floor plan of the store.
While people were 13 percent more likely to buy foods with organic labels on them if they brought their own bags, they were also 7 percent more likely to buy more foods that were high in sugar, salt and fat like potato chips, cookies and ice cream.
Lead study authors Uma Karmarkar and Bryan Bollinger concluded that this uptick in junk food purchase has to do with something called the licensing effect, or the idea that because shoppers felt they were doing something good for the environment, they could treat themselves.
“In short, bringing your own bags changes the way you shop," the authors wrote in a press release. "In stores where reusable bags are popular, marketing organic or sustainably farmed foods as indulgences could increase the sales of those items.”
Don't let this stop you from bringing your own bags, which really is a great service to the environment. Plastic bags take between 15 to 1000 years to decompose, and paper bags aren't much better -- one study found that compostable plastic and paper bags require more material while being manufactured, meaning more energy, fuel and raw materials are being used to make them.
Keep bringing your own bags. Just be aware of what you're putting in them.
H/T The Atlantic
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