Do you always add parmesan cheese? (iStock)

For years you’ve been telling your friends, family, co-workers and anyone who will listen that you’re addicted to cheese. It’s a part of every meal or snack, and you think about it constantly. According to a study from the University of Michigan, cheese crack is a real thing. And so is your addiction.

The study, published in the journal Plos One, examines why certain foods are more addictive than others. Researchers identified addictive foods from about 500 students who completed the Yale Food Addiction Scale, designed to measure if someone has a food addiction.

Pizza, unsurprisingly, came out on top of the list of most-addictive foods. Besides being a basic food group for kids, college students and adults, there’s a scientific reason we all love pizza, and it has to do with the cheese.

The study found that certain foods are addictive because of the way they are processed. The more processed and fatty the food, the more it was associated with addictive eating behaviors.

Cheese happens to be especially addictive because of an ingredient called casein, a protein found in all milk products. During digestion, casein releases opiates called casomorphins.

“[Casomorphins] really play with the dopamine receptors and trigger that addictive element,” registered dietitian Cameron Wells said.

So there you have it. Your cheese addiction has been validated by science.