Congratulations to Pizza, Recently Voted The World's Most Addictive Food

Limiting yourself to two slices of pizza is unnatural. In fact, to do so is to defy science.
Publish date:
March 3, 2015
junk food, food science, pizza, food addiction, recently in science

Trigger Warning: This article discusses food addiction and binge eating and may be triggering to some.

The wise and wonderful Emily McCombs once said “I kind of don’t even want pizza if I can only have one slice.”

There is such truth in that tweet. The idea of only having once slice is cruel. It takes me at least two to get warmed up, which is why I've never understood those articles that prattle on about how “pizza can actually be kind of good for you if you get thin crust, and light cheese, and extra veggies and only have two slices." Not only is that completely missing the point of pizza, but limiting yourself to two slices of pizza is unnatural. In fact, to do so is to defy science.

According to a recent study by Erica M. Schulte, Nicole M. Avena, and Ashley N. Gearhardt, the more processed, sugary, or fatty a food is, the harder it is to stop eating it. Pizza beat out the 34 other foods used in the study, emerging victoriuous and claiming the title of “most addictive food."

Congratulations pizza, though let it be known that I never doubted you for a moment. (It should be noted however, that calling pizza "the most addictive food in the world" as I just did in the title isn't entirely accurate, as only 35 foods were tested, but you get the idea.)

While the idea of “addictive” food is somewhat controversial among researchers (and the warring voices in my head), it’s undeniable that certain foods are harder to stop eating. I've always thought that this is because salty, sugary, and fatty foods taste really good, but Schulte et. al., think that the inability to "eat just one" potato chip has less to do with flavor and more to do with foods' addictive properties, which they posit work in a way that is similar to drugs.

Much like the term “drug,” which can encompass both addictive (e.g. heroin) and non-addictive (e.g. aspirin) compounds, the term “food” is also broad and refers not only to foods in their natural state (e.g. vegetables), but also those with added amounts of fat and/or refined carbohydrates (e.g. cake) or artificial sweeteners (e.g. diet soda).

Addictive substances are rarely in their natural state, but have been altered or processed in a manner that increases their abuse potential. For example, grapes are processed into wine and poppies are refined into opium. A similar process may be occurring within our food supply. There are naturally occurring foods that contain sugar (e.g., fruits) or foods that naturally contain fat (e.g., nuts). Notably, sugar (or refined carbohydrates) and fat rarely occur in the same food naturally, but many palatable foods have been processed to have artificially elevated quantities of both (e.g. cake, pizza, chocolate).

Before we go any further, I think it's important to understand that when the researchers are talking about "food addiction" they do not mean "eating addiction" and the difference between these two terms is at the center of the debate over whether or not food companies should be held responsible for selling "addictive substances." According to the authors of the study highly-processed foods may be to blame for the "obesity epidemic."

But John Menzies, Ph.D., a University of Edinburgh researcher disagrees. According to an article on the Huffington Post, Menzies believes that focusing on the food itself is the wrong approach, and that human behavior is what we should be studying:

'Food addiction' has been implicated as a potential contributor to the obesity epidemic,” wrote Menzies in an email to HuffPost. "However, there is no association between diagnoses of addictive-like eating and body weight.

'Eating addiction' shifts the focus away from the food itself to the behaviour,” he wrote. "It emphasises that we need to look carefully at people's relationship with food and understand how people make their food choices.”

Personally, I tend to agree with Dr. Menzies, but that's mostly because I've seen people exhibit addictive behavior toward iceberg lettuce and rice cakes, neither of which fall into the "high-sugar, high-fat" category of foods. Plus, I don't expect snack companies to provide me with nourishing, balanced meals. If they make a chip I can't quit putting in my mouth, I consider they've done their job. Is it a saintly job? No. It's actually a little evil, especially when you consider "the children" and all of that, but from a scientific standpoint, I am always impressed.

But then there are the rats. (Rats are unavoidable in discussions such as these.) According to Shulte, et. al.:

Although there is little evidence in humans of what foods may be addictive, animal models suggest that highly processed foods are associated with addictive-like eating. Rats with a propensity towards binge eating exhibit addictive-like behavior in response to highly processed foods, such as Oreo Double Stuf cookies or frosting, but not to their typical chow [28,29]. Rats maintained on a diet of highly processed foods, such as cheesecake, exhibit down regulation in the dopamine system that also occurs in response to drugs of abuse [30]. Further, rats are motivated to seek out highly processed foods despite negative consequences (foot shock), which is another feature of an addiction [31]. Therefore, at least in animal models, overconsumption of highly processed foods, but not standard rat chow, appears to produce some addictive-like characteristics. This reinforces the idea that not all foods are likely to be equally associated with addictive-like eating behaviors.

In her interview with HuffPostLive, Dr. Nicole Avena (one of the studies authors) explains that the solution is education: "I think a lot of it has to do with education and understanding that you know if you're posed to eat pizza that it might be a good idea to try to put the brakes on after maybe just one slice. We are now finding research that's suggesting that these foods can be very very difficult to control our intake of. So I think having that awareness and knowing that there could be effects on the brain and changes in response to over-eating these foods continually, I think that can really help people to try to understand that they may need to take a different approach when trying to moderate their food intake."

Suggesting that the someone with a pizza addiction only have one slice seems kind of like telling an alcoholic to only have one beer, but Avena was probably trying to avoid "being that crazy woman who told people to stop eating pizza."

Honestly, I don't think pizza's appeal lies exclusively in fat, sugar and salt. Sure, they are definitely contributing, but oddly enough, when I first read that pizza had been crowned "most addicting," my mind didn't go to gooey cheese or greasy pepperoni, but to Doritos.

Over a year ago, The New York Times published a piece illuminating exactly why Nacho Cheese Doritos are impossible to quit eating. If my husband and I shop while hungry (SWH is very dangerous), we'll inevitably end up with a bag of Nacho Cheese Doritos. They rarely last the car ride home.

The Dorito is fascinating from a scientific standpoint. Considering that they are engineered to be delicious, you and your mouth never stood a chance. Fat, salt, and MSG all play their parts, but the real trick is how the various flavors play across your tongue:

Despite the powerful tastes in Nacho Cheese, the Doritos formula balances them so well that no single flavor lingers in the mind after you've eaten a chip. This avoids what food scientists call “sensory specific satiety,” or the feeling of fullness caused by a dominant flavor. Would you eat a whole bag of rosemary chips? With Doritos, you go back for more.

The lack of "one note-ness" keeps your chip-eating interesting; your mouth never gets bored because it's never exposed to one flavor for very long. The same could be said for pizza.

The sauce alone is a symphony of spices and, if you get a lot of toppings, you can keep your tongue interested for hours. Who hasn't finished the last bit of chewy crust, with it's little bits of burnt cheese, to suddenly be hit with the desire to revisit pepperoni's salty umami, or the burn of a jalapeno slice?

In food, there's a fine line between "addicting" and "so good you don't want to stop eating." Binge eating isn't restricted to processed foods, and by focusing to heavily on those, we may miss out on the chance to examine our relationships and attitudes toward eating and food as a whole. Foods with fat and sugar may very well be more addicting than those without, but it's most likely not the whole story and shouldn't be the only thing we talk about when discussing addictive behaviors around food.

I've powered through a minimally-processed pound of prosciutto at a pace that I am not very proud of. I've made myself sick on fresh-picked cherries. I though I was addicted to Diet Coke, until I realized that I'll drink any canned beverage at an absurd rate and started buying La Croix instead. (Which I now drink 5 to 8 cans of a day; I suspect I like the aluminum.)

It is easier to binge on processed food. These things are engineered to taste better and they're usually very convenient. But food is one of those very personal subjects for which there is no "one size fits all" solution.

Rats may be unable to shake the allure of the Oreo, but we are not rats. We have the ability to listen to our bodies and understand how our choices impact how we feel, both physically and emotionally. Eating an entire pizza on a daily basis would make me feel terrible, but every once in a while? It feels amazing.