It's not difficult to pinpoint the types of people who hate cheese: vegans, lactose-intolerant individuals, sociopaths. Cheese-haters who don't fall into these categories often have an innate distaste for cheese and their peculiar preferences may have less to do with personal taste — in fact, it just might be genetic.
According to Harold McGee, author of On Food and Cooking: The Science and Lore of the Kitchen, evolution could be at play. It's a phenomenon McGee calls "controlled spoilage."
Over time, humans have learned to avoid decomposing food. The reasons are obvious: food that is going bad comes with health risks. Since cheese is technically made by milk proteins breaking down — it is essentially in the midst of the decaying process — it comes with odors that are associated with food going bad. In some cases, like Gorgonzola and blue cheese, the effects are heightened since there's actual mold in the cheese.
"An aversion to the odor of decay has the obvious biological value of steering us off whiffs of shoes and soil and the stable takes some getting used to," writes McGee, reports Extra Crispy.
The notion of genetics messing with a person's potential for loving cheese isn't so outlandish when you consider people's distaste for cilantro. Scientists at Cornell University conducted a genetic survey to identify a single gene — the OR6A2 gene — responsible for this effect. This gene "codes for the receptor that picks up the scent of aldehyde chemicals" — these chemicals are found in cilantro and soap, which is why many people anecdotally say cilantro tastes like soap.
Something similar is at play with cheese. According to consumer genetics testing company 23andMe, similar chemicals can be found in cheese and body odor, which can explain why some people are so repulsed by cheese.
"The same chemical can be found in both appealing and unappealing places — cheese and body odor, for example," 23andMe wrote in a blog post. "Conversely, the same ingredient — such as cilantro — can contain both pleasant and unpleasant chemicals. Whether stinky cheese and cilantro are delicious or disgusting depends on your particular perception of many different chemicals."
So, next time your friend says "no" to adding cheese to their burger, just remember that they're not monsters — it's genetics.