Today, it's hard to find an item on a restaurant menu that isn’t drenched in cheese, and as it turns out, there may be a scientific explanation for this. According to a recent study, cheese isn’t just delicious, it’s actually addictive. Oddly enough, despite cheese’s addictive characteristics, this food's actually quite unpopular outside of Western culture.

For the study, researchers from the University of Michigan had 500 undergraduate students complete the Yale Food Addiction Scale, a test designed to determine which foods consumers find more addictive. Results revealed that certain foods may be more addictive than others because of the way they're made; the more processed and fatty the food is, the more likely it was to be associated with addictive eating behaviors.

However, the team found that along with being highly processed and fatty, cheese has one other quality that keeps bringing us back for more: casein, a protein found in all milk products. According to the Los Angeles Times, when we digest casein, it releases opiates called casomorphins, which essentially trigger happy dopamine receptors in a similar way to drugs.

"[Casomorphins] really play with the dopamine receptors and trigger that addictive element," registered dietitian Cameron Wells told Mic.

While it’s still debatable just how much of an opioid effect casomorphins actually have after milk is processed into cheese, just a quick scope of any U.S. dairy aisle will show that Americans can’t seem to get enough of the stuff. Mic reported that since the 1970s Americans have more than tripled their cheese consumption, and if Domino's Pizza commercials are any testament, they don’t seem to be slowing down anytime soon.

However, despite cheese’s popularity in the U.S. and other Western nations, this popular food is a rare find in other parts of the world. For example, in far Eastern cultures, such as in China, traditional dairy products are associated with nomadic people and “barbarian” lifestyles, Slate reported. While today you’re likely to see Chinese people in larger cities snacking on cheese, the food is still largely absent in the smaller provinces. Cheese is also absent from the menu in many traditional African cuisines, and the only type of cheese typically prepared in India is paneer, a type of milk curd. In fact, nearly all of the countries with the highest cheese consumption are located in Europe and North America, Cheeserank reported. A large reason for this may also be due to the higher rates of lactose intolerance in the East versus the West.

Trouble digesting lactose, the main sugar in dairy products, is also known as lactose intolerance. Individuals with this condition will develop intestinal symptoms, such as bloating, diarrhea, and gas after eating dairy-based products. The degrees of intolerance vary from individuals, but the National Institutes of Health reports that most individuals with this condition can only tolerate eating hard cheeses, such as cheddar and Swiss.

According to the National Library of Medicine, while around 65 percent of the human adult population has trouble digesting lactose, only 10 percent of Americans and 5 percent of Northern Europeans experience this problem, compared with more than 90 percent of individuals of East Asian descent and 70 to 90 percent of Africans.

Source: Schulte EM, Avena NM, Gearhardt AN. Which foods may be addictive? The roles of processing, fat content, and glycemic load. U.S. National Library of Medicine. 2015.