Science says being hungry not only makes you want to buy food, it can also lead you on an expensive shopping binge.

Thinking about skipping lunch so you can hit the mall? Think again.

A recent study published in Proceedings of the National Academy of Sciences has linked unsatisfied hunger to a desire to buy non-food items.

In other words, your empty belly may be to blame for your empty wallet.

The study involved 379 volunteers who took part in five behavioral experiments. The results indicate hunger has a direct impact on how many items a person buys, even if the items themselves can’t satisfy hunger.

When offered sample binder clips to take home, for example, those participants who rated themselves as hungrier took more clips than those who were not as hungry.

“There are many studies that show that whatever is on your mind at a given time can influence which opportunities for behavior you see, and what you’re likely to do and how you interpret things,” said Norbert Schwarz, study author and a provost professor at the University of Southern California. “In the case of hunger it’s pretty straightforward. If hunger means ‘I want to get food,’ then ‘getting stuff’ may be on your mind. When you then have the opportunity to ‘get stuff,’ you may take a few things that are available that have nothing to do with satisfying your hunger.”

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One of the experiments in the study involved analyzing the receipts of shoppers exiting a department store. The data from the receipts showed that those who were shopping with a growling belly not only bought more non-food items than those who were full, but that the hungry shoppers also spent more money in total.

“If you’re worried about spending too much money, you may be better off going [shopping] after lunch rather than before lunch,” Schwarz noted.

According to Alison Jing Xu, another author of the study and a professor of marketing at the University of Minnesota’s Carlson School of Management, the realization that hunger increases motivation to spend has a direct impact on how consumers should plan their purchases.

“One takeaway from the research is that, well, if you plan to go shopping, either by going to a shopping mall or shopping online, think about feeding yourself before doing that,” Xu said.

Xu also noted the importance of keeping regular meal times so as not to make rash decisions driven by hunger.

“If you have to make decisions and you feel kind of hungry, be aware of the possibility that you may spend more money than otherwise,” she said. “You can probably arrive at more rational decisions when you’re not hungry.”

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Dieticians support the study findings. They generally advise eating a combination of balanced meals and healthy snacks to avoid acquiring unwanted objects as a result of hunger.

“I would recommend having a snack or a meal prior to running errands or grocery shopping,” says Natalie Beck, a registered dietician and founder of Full Belly Nutrition. “When we start to feel really hungry, we can become less thoughtful about what we should be eating and focus more on satisfying that hunger, which can result in buying something unhealthy, or as the [study] mentioned, [buying] something not food-related at all.”

Beck says that meals made up of a combination of fats, protein, and carbohydrates are essential for keeping hunger at bay. They can be supplemented with snacks such as sliced fruit, nuts, a granola bar, or unsweetened yogurt.

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