Can't Shake the Shake Shakes


In a new study published by the Archives of General Psychiatry, researchers at Yale's Rudd Center for Food Policy and Obesity used functional magnetic resonance imaging (fMRI) to look at the brain activity of women presented with a picture of a chocolate milkshake. They found that higher scores on their Yale Food Addiction Scale—which asks subjects to agree or disagree with statements such as, "I find that when I start eating certain foods, I end up eating much more than I had planned"—"correlated with greater activation in the anterior cingulate cortex, medial orbitofrontal cortex, and amygdala"—brain regions associated with pleasure and craving—"in response to anticipated receipt of food." When the subjects with high scores drank the milkshake, by contrast, they "showed less activation in the lateral orbitofrontal cortex," a brain region associated with self-control. These patterns are similar to those seen in drug addicts. According to The Hartford Courant, this similarity "suggests that a chocolate milkshake and a line of cocaine might not be so different." The Globe and Mail likewise suggests that if you find yourself "craving a milkshake," "you might be a junk-food addict," while The Wall Street Journal worries that "food may be addicting to some," and WLS, the ABC affiliate in Chicago, reports that "for some people food does seem to act like a drug on the brain."

All addictions—defined as hard-to-break attachments to things that provide pleasure or relieve stress—share common features, and it is not surprising to find these similarities are reflected in brain activity, as is everything that humans think, feel, experience, or do. But the notion that you need fMRI images to show that people can be addicted to certain kinds of food is absurd. People can be addicted to just about anything. And as psychologists such as Stanton Peele and Jeffrey Schaler point out, addiction can be good, bad, or neutral. Although it is perfectly meaningful to say you are addicted to good books, trashy TV, sex, exercise, blog reading, or love (just ask Robert Palmer), that does not mean you should give up these attachments. An addiction can be life-enhancing or self-destructive, and its consequences depend to a great extent on how it is treated by the law. When the Journal's Kevin Helliker says food addicts, unlike drug addicts, do not steal to support their habits, he is not identifying an inherent difference between milkshakes and heroin; he is observing a side effect of a government policy that makes heroin much more expensive than it would otherwise be.

When it comes to illegal drugs, official propaganda teaches that the power of addiction arises from the  quasi-magical properties of a particular substance. Anyone who has considered the research on patterns of drug use knows there is no such thing as an ineluctably addictive drug. But the public and the press tend to accept the government's claims about addiction to illegal drugs, at least with respect to such reputedly irresistible substances as crack, methamphetamine, and heroin. Hence the resistance to comparisons between milkshakes and cocaine. The stories about this study are careful to note the plain truth that food addiction occurs only in "some" people. Yet the same thing is undeniably true about drug addiction, as Reason contributor Maia Szalavitz perceptively notes in Time:

Is Häagen-Dazs ice cream as addictive as heroin? Or, put another way, is heroin as addictive as Häagen-Dazs?

Depending on how you phrase the question, you're either asking whether heroin addiction is no more serious than a love of junk food, or you're questioning whether junk food junkies may have a serious disorder that needs intervention….

Notably, the study also found that food addiction symptoms and brain responses to food were not associated with weight: there were some overweight women who showed no food addiction symptoms, and some normal-weight women who did.

That's why addictions aren't simple: they involve variations not only in levels of desire, but also in levels of ability to control that desire. And these factors may change in relation to social situations and stress.

Neither heroin nor Häagen-Dazs leads to addiction in the majority of users, and yet there are certain situations that may prompt binges in people who otherwise have high levels of self-control. So the answers to addiction may lie not in the substances themselves, but in the relationship people have with them and the settings in which they are consumed.

What are the policy implications of this debate? Former FDA Commissioner David Kessler blames obesity on "hyperpalatable" foods that manufacturers and restaurant chains deliberately design to taste good (those bastards!). Kelly Brownell, the psychology professor who heads the obesity research center that produced this study, focuses on the "food environment," which includes not just the food itself but its price, its convenience, and all the cues, such as advertising, that encourage people to consume it. Both critiques suggest that regulation is necessary to stop evil corporations from taking advantage of people's uncontrollable impulses. But if food addiction is resistible, if it affects only a minority and does not necessarily lead to unhealthy overreating, it is not a very powerful argument for restrictions that affect everyone.