By Aly Walansky
Updated May 12, 2016
Credit: © ClassicStock / Alamy

We already know that it’s not wise to go to the grocery store when you’re hungry, but a new study says the times when we’re feeling peckish are times we should avoid making any decisions at all.

When we are hungry, we tend to make more impulsive (and almost always worse) food choices. The reason for this is a hormone named ghrelin, known to increase appetite, and negatively impact decision making and impulse control – whether that decision is related to what we’re eating, or not.

In a study completed at Sahlgrenska Academy at the University of Gothenburg the team observed rats and their impulse control before eating dinner. The rats were trained by receiving a sweet snack when they would press a ‘go’ lever or when they resisted pressing the ‘no go’ lever. Not pushing the lever indicated good impulse control. During the study, rats were injected with ghrelin in such a way as to mimic the way the way the hormone naturally tells us to we ought to eat when we’re hungry, and the scientists noted that when injected, the rats were unable to resist pressing any of the levers. The “hungry” feeling decreased their impulse control and decision making skills. "Our results showed that restricting ghrelin effects to…the part of the brain that is a crucial component of the reward system, was sufficient to make the rats more impulsive. Importantly, when we blocked ghrelin, the impulsive behavior was greatly reduced,” said Karolina Skibicka, associate professor and lead on the study.

When it comes to what we humans should do, the best way to stay in control of hormone-dictated impulses is to maintain a healthy diet. When you eat solid food, the nerves in your stomach and intestine tells your brain you are full and suppresses ghrelin. According to Mona Dolgov and Robert Warden, nutrition experts and co-authors of The Perfect Portion Cookbook, "Try to eat healthy 100 calorie portions every four hours, since ghrelin is produced and secreted on an estimated four-hour schedule. Keeping these hunger hormones at bay is best when you can eat on a schedule. Eat at least three meals, and one to two solid food snacks every 3-4 hours daily."