new proof of something we allo if we stop to grab groceries a little hungry. Here's abc's paula faris. Reporter: There's a new reason to fill up before filling your cart at the grocery store. Today, a... See More
new proof of something we allo if we stop to grab groceries a little hungry. Here's abc's paula faris. Reporter: There's a new reason to fill up before filling your cart at the grocery store. Today, a study out of cornell says when you shop hungry, you're buying 23% fewer healthy foods than you would buy if you weren't. And, according to the study's author, we're not buying more food as was previously thought. We're simply buying worse food. You buy less of the good stuff and more of the convenient, highly processed, easy foods. Reporter: If you are not hungry, you're probably gravitating towards the healthier option. But if you are hungry, most likely going with non-healthy. And you'll be living with those choices the rest of the week. You've loaded up with cereal, chips, candy, and it's going to be eaten eventually. Reporter: You may have seen wansink's experiments before. He studies mindless eating. The endless bowl of soup -- piping in extra soup. People keep on eating because the bowl isn't empty. And plate size. People eat less on smaller plates. In a lot of cases we make much more rash decisions when we're hungry. Reporter: The grocery guru said it can take only five hours without eating to become more impulsive. The solution? Eat an apple before your next trip to the store. A little food for thought. Paula faris, abc news, new york.
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