An investigation into the potential addictiveness of high-fat and high-sugar foods has found that Oreo cookies activate more neurons in the pleasure centers of rats' brains than cocaine. But does that really mean certain foods are more addictive than hard drugs?
These findings, which will be presented by Joseph Schroeder at the Society for Neuroscience conference in San Diego next month, show — quite alarmingly — that foods high in fat and sugar stimulate the brain in the same way that drugs do — if not more so. The research apparently helps to explain why some people can't resist these types of foods despite the fact that they're aware of how bad it is for them.
Instilling addiction
Here's how the Connecticut College researchers reached their conclusion:
In the first of two experiments, rats were put into a maze and given two choices depending on their location: either a salty drink or a cocaine injection (sometimes a morphine injection). The rats quickly learned to navigate to the part of the maze where they could get a hit of the cocaine.
In the second test, the rats were likewise put into a maze, but this time they could choose between areas that offered either rice cakes or an Oreo cookie. To no one's surprise, they learned to loiter around the cookie stand (yes, even rats hate rice cakes).
So at this point it's clear that the researchers, by offering rewards, conditioned a preference for a certain place in the maze. Now, this isn't addiction per se, but it's an important component of what makes something addictive.
C-Fos, activate!
After, by measuring the expression of a protein called c-Fos in the brains of the rodents, the researchers found that the cookies activated more neurons in the accumbens – a region of the brain associated with pleasure, and studied for its role in addiction and reward-processing – than addictive substances like cocaine. It basically told the researchers how many cells were turned on in a specific region of the brain in response to the drugs. Or Oreos.
“This correlated well with our behavioral results and lends support to the hypothesis that high-fat/ high-sugar foods are addictive,” explained Schroeder.
Interestingly, drugs like cocaine, crystal meth, and heroin have been shown to increase c-Fos production in the human prefrontal cortex as well as in the mesolimbic reward pathway. Consequently, it's a crucial component for neuroscientists as they try to better understand addiction.
But does it correlate with food?
Neuroscience major Jamie Honohan, who also worked on the study, noted in a press release that: “Even though we associate significant health hazards in taking drugs like cocaine and morphine, high-fat/ high-sugar foods may present even more of a danger because of their accessibility and affordability." It's a problem, she says, because many products like these are heavily marketed in communities with lower socioeconomic statuses.
This is obviously very important research, particularly as we find ourselves in the midst of an obesity epidemic. But as behavioral neuroscientist Bethany Brookshire (aka scicurious) notes in this overview of overeating and obesity, should we really call it a food addiciton? Can it really and truly be said that "addiction" to food is the same as an addiction to hard drugs? If yes, it's a conclusion that seems rather... off. It doesn't seem quite right. And indeed, there's no consensus about this among researchers right now, but it's clearly an important issue moving forward.
As a final aside, Schroeder told Today.com that he hasn't touched an Oreo since doing the experiment. Oh, and when it came to eating the cookies, the rats preferred to eat the center first.