Whether you occasionally raid the drive-thru or keep your desk drawer stocked with chocolate, you probably have a go-to craving. But what’s behind the hankering?

Discover these four scientific truths about cravings, and learn how to crush yours.

1. Cravings Start In Your Brain—Not Your Body 

Experts used to suspect that if you craved a burger, you were low in iron, and if you craved chocolate, your body needed magnesium. But if the root of all cravings was nutritional needs, we’d all be jonesing for kale, says nutritionist Jaime Mass, R.D.

Instead, research suggests that most cravings have more to do with your brain than your body.

As it turns out, sugar and fatty processed foods trigger the same areas of your brain as drugs do. And that causes a release of the feel-good neurotransmitter dopamine, which means your brain wants you to keep going back for more, says Mass.

That’s why you crave the foods that got you high in the first place.

2. Sugar Trumps Fat

While both sugar and fat light up your brain’s pleasure centres, you’re more likely to crave donuts than bacon, according to a study published inThe American Journal of Clinical Nutrition.

Researchers tracked the brain activity of more than 100 students as they drank chocolate milkshakes that were either high in sugar or high in fat and contained the same number of calories. The scientists found that the sugar-laden beverages were more effective at activating areas of the brain linked with compulsive eating than the fattier shakes.

3. Poor Sleep Can Lead To Cravings

When you’re tired, you’re more likely to crave carbohydrates and sugar to pick yourself up, Mass says. Plus, you might feel hungrier in general because your levels of the hunger-regulating hormones leptin and ghrelin are thrown off, she says.

In fact, in one 2012 Mayo Clinic study, people who slept 80 minutes less than they usually did wound up eating an extra 550 calories the next day.

4. Your Supermarket Is Plotting Against You 

When you grab that candy bar in line at the supermarket checkout, you probably think you’re satisfying a spontaneous chocolate craving. But it’s not that simple.

“Manufacturers pay what are called ‘slotting fees’ to grocery stores so that their products are placed in areas where you’re most likely to see them, like the checkout [line] and any eye-level shelves,” says Collin R. Payne, Ph.D., associate professor of marketing at New Mexico State University.

2. Fire Up Tetris On Your Phone

Playing the classic block game for just 3 minutes is enough to slash food, caffeine, and nicotine cravings by 24 percent, finds a British study.

The bright colours and moving shapes in the game scramble your brain’s ability to visualize whatever it is you’re craving, the researchers say. And the effect lasts even after you quit the game.

Additional reporting by Lisa Freedman.

The article 8 Things You Definitely Never Knew About Food Cravings was originally published by our partners at WomensHealth.com.