forkYou know that old adage about how you’re never supposed to go grocery shopping while hungry? The reason being is that you’ll end up with a thousand more items in your shopping cart than were on your list–and most of them junk food.

Well, now a study in the journal Neuropsychopharmacology reveals that you shouldn’t make important decisions while hungry, either. And, since you tend to be hungrier during the second half of your cycle (the day after ovulation through the day before your next period) due to progesterone, which amplifies your appetite, this is an especially important heads-up to keep in mind during these cycle days.

Here’s why: When you haven’t eaten in awhile, your body produces ghrelin–a hormone that revs your hunger, telling you it’s time to put food in your belly. Well, according to researchers from Sweden’s Sahlgrenska Academy at the University of Gothenburg, when ghrelin spikes, you’re prone to being more impulsive and, therefore, making less rational decisions. That’s because this hormone affects a certain region of the brain–the ventral tegmental area–involved in feelings of reward.

What’s this mean for you? If you’ve got an important decision to make and you’re making it while hungry, you’re liable to pick the option that has an immediate reward but comes with long-term losses. For example, you might select a new bank because it promises to give you $50 to open a new savings account, however, its interest rate is significantly lower than its competitors, so you end up with less money down the line. Or if you’re choosing between two job offers, you might select the position that starts with a higher salary, but has fewer chances for promotions and career growth later on than the other position you were offered.

The bottom line: When you’ve got a weighty choice to make, be sure to eat a meal or snack before you pick your choice during every day of your cycle, but especially during the latter half when hunger is more frequent.

[Photo: Chaquetadepollo.]