Never go shopping hungry — not just grocery shopping but any kind of shopping. Hunger increases our biological intention to consume, and out of desperation the body manifests consumerism in one form or another. Researchers from the University of Minnesota’s Carlson School of Management recently decided to take a closer look at this psychology of an empty stomach and published their findings in the journal Proceedings of the National Academy of Sciences.

“Hunger makes us think about seeking, acquiring, and consuming food,” the study’s coauthor Alison Jing Xu, assistant professor of marketing at the Carlson School, said in a press release. It’s one of five studies Xu and her team have conducted to understand how hunger has the ability to control certain aspects of our lives. “The acquisition-related thoughts can spill over and put us in a mode of also getting nonfood items even though they are incapable of satisfying our hunger.”

First, they asked the study’s participants to look at a variety of a common office item: binder clips. Half of the group was given a blind taste test of different cakes, while the other group was forced to make shopping decisions while they were still hungry. The participants with rumbling tummies wanted 70 percent more binder clips than the satiated, cake-filled group.

To reinforce the notion that hunger hurts our wallets, researchers measured a typical mall-goer's hunger levels and then took a look into their shopping bags. The hungrier the shopper said he was, the more money he spent — 64 percent more.

Previous research found being hungry, having to pee, feeling sleepy, or sexually stimulated can actually override our control center and affect our behavior. Studies show embodied cognition is a strange phenomenon in which the body and mind are connected in a way that allows one to control the other. All of a sudden, because our body is hungry, our minds become slaves to something more primitive: consumption.

The juxtaposition between food consumption and nonfood consumption draws a direct line into our mind-body experience. The relationship between the two strengthens indelibly and a common reliance on each is welded. The body needs the mind to fulfill the innate driving force of food survival.

So, do yourself and your budget a favor by grabbing a bite to eat before you hit your favorite department store. The more options, the more the brain craves to fill the empty spot inside of you with new shoes, a purse to match, a new grill set, or even a spare pair of golfing gloves — the more, the better, right?

“If you go for a shopping trip with an empty stomach you may spend more money and buy more stuff than you otherwise would,” Xu said. “Why not feed yourself before a shopping trip? Alternately, if you are hungry and you have to make purchasing decisions, think twice before you buy. “

Source: Wyer RS, XU AJ, and Schwarz N. Hunger promotes acquisition of nonfood objects. Proceedings of the National Academy of Science. 2015.