In 2015, a story emerged that had the unlikely effect of galvanising both cheesemongers and drug dealers. A study from the University of Michigan made front pages around the world when scientists seemed to claim that eating cheese could produce effects similar to a dose of Class A narcotics. Despite almost no known cases of a proclivity for fondue spiralling into the climax of “Requiem for a Dream”, papers everywhere went batty. Cheese has felt extra naughty ever since.
A closer look at the study reveals that there’s more to cheese’s new reputation than sensationalist headlines. The team used the Yale Food Addiction Scale, a measure used to rank relative cravings for a particular ingredient, to determine that cheesy food scores just as highly as other famously moreish snacks, such as chocolates and crisps. 120 students were asked to rank 35 separate foods, and the results clearly indicated that cheese-heavy ingredients were almost unanimous high scorers.
The study suggested that one reason for cheese being so irresistible is down to the presence of the chemical casein - a complex protein molecule that, once it has been broken down during digestion, triggers the brain’s opioid receptors in a way not dissimilar to hard drugs like cocaine and heroin. On paper, this sounds like bad news for anyone who likes to round off dinner with a cheeseboard.
While casein is found in every dairy product, there is something unique about the way in which cheese is made that makes it an unusually potent source. Since producing a pound of cheese takes around 10 pounds of milk, the casein content is going to be much more highly concentrated, meaning that any effects are likely to be heightened. Once these high doses of casein have been consumed, the brain’s pleasure centres are stimulated, producing effects similar to other enjoyable activities, including drug use. This, some say, is why cheese is one of the most addictive foods out there.
For anyone with fond memories of four cheese pizza or cheddar toasties, this news could leave you feeling pretty bleak. Obviously, drugs are bad. It’s no great stretch to assume that anything associated with them in any way must also be bad. However, the years since the study’s publication have seen some critics call into question the comparisons being made between our food and illegal substances.
One common criticism from the scientific community has focused on the misinterpretation of the original study’s findings. Many have pointed out that, though cheese-heavy foods such as pizza did indeed come out at the top of tree for foods categorised as “most addictive” by the 120 students who took part, the presence of cheese is actually a red herring. The study itself actually suggested that it was highly processed, fat and salt-rich foods that were the most likely to cause a craving. Casein, by contrast, was a relatively insignificant factor. Cheese only ranked as 16th out of 35 foods for addictiveness - lagging way behind ingredients such as chocolate and French fries.
A good deal of the criticism has come, somewhat surprisingly, from the study authors themselves. Ashley Gearhardt, who helped lead the project, revealed in the aftermath that she “...was horrified by the misstatements and the oversimplifications…and the statements about how it’s an excuse to overeat. Liking is not the same as addiction. We like lots of things. I like hip-hop music and sunshine and my wiener dog, but I’m not addicted to her. I eat cheese every day. That doesn’t mean you’re addicted or it has addictive potential.”
As the authors tried to explain, to little or no avail, there is a distinct difference between pleasure-inducing foods and narcotics. As Joseph Frascella, a neuroscientist at the National Institute on Drug Abuse in Bethesda, explained in an interview with Science News, “We know there are these areas of the brain, reward circuits involved in keeping us alive. They are systems that signal to us when something we do is good, like eating, procreating or drinking water when you’re thirsty.” It is these systems that drugs exploit.
In reality, it is not a question of cheese behaving in a similar way to cocaine, but instead of the drug taking advantage of existing biological pathways and frameworks to induce an effect. The same pleasure sensors that are essential to our survival are what drugs look to stimulate. It’s not a question of everything pleasurable being bad - it just goes to show the biological power of dangerous substances. As Peter Kalivas, a neuroscientist at the Medical University of South Carolina, also explained to Science News, “Addictive drugs do things that food doesn’t do that make them more addictive. To put [those foods] on par with something like cocaine is pretty inflammatory.”
Though it doesn’t make for anywhere near as exciting a headline, the truth is that feeling good about food isn’t necessarily a bad thing. It certainly isn’t fair to mention something as delicious as cheese and something as damaging as crack cocaine in the same breath. While understanding that some foods that should be seen as a treat can have a dangerously tempting effect, it’s taking things too far to assume that a wheel of brie is as lethal as a bag of meth. Pseudo-scientific scaremongering aside, you aren’t actually going to need to head to cheesy rehab anytime soon.