We talked last time about the validation given by the recent Yale study, to the idea that food addiction is a reality for some people. Of course, the story was immediately picked up and expanded on by numerous other media, all with their own particular slants.
For basic information about how the study was conducted, and answers to some specific questions, Christine Stomes has composed a very straightforward and clear guide through all the details. This subject is of great interest to medical professionals and the parents of kids who are worried about childhood obesity, not to mention public health officials. William Weir, reporting for the Columbia Daily Tribune, quoted Ashley Gearhardt, the study’s lead researcher, who said, “This past year, we got interested in the idea of food addiction and the neural process… We just wanted to get down and deep into whether people really experience food addiction.”
Weir relates Gearhardt’s explanation about how our attraction to sugary and fatty food is an atavistic urge that was useful to humans in an earlier stage of our development. Those were desirable energy sources, and it was good that the knowledge was hard-wired, to give us the impetus to seek out foods that supplied energy.
The difference is, in those harsh old days, there was little danger of anyone getting their hands on enough sweets or enough fat to create a problem. In the days before mass-production and global retailing, subsistence economies were exactly that. There wasn’t enough of anything to go around, and it was mostly vegetables, grains, legumes, and boring stuff like that. While there might have been enough alcohol to get people hooked, seldom was there enough food to sustain anybody’s potential addiction.
But now, we still have that same instinctual craving for dangerous foods that are no longer scarce but everlastingly abundant almost everywhere. That drive to stoke our bodies with substances that are only good in very small quantities, it doesn’t know how to quit when large quantities are available. The anachronistic urge for those problem foods is what gets us in trouble. Dr. Pretlow is not so sure about this:
The Yale researchers may be missing the point here. Their assumption that high fat, high sugar foods are consumed preferentially, because of instinctual need for the highest calories, may be incorrect. If this were so, then we’d eat pure sugar and pure fat (imagine eating packs of sugar or drinking corn oil or bacon grease) – that just doesn’t happen. It therefore seems to be the pleasurable sensations (taste, texture) and action of eating (biting, chewing, tongue action, swallowing) that drive this consumption. Pleasurable sensations ease emotional discomfort, at least temporarily, and the action of eating constitutes displacement activity which relieves stress. When the brain realizes this effect (actually the emotional, central part of the brain) the behavior will be repeated, striatal dopamine receptor changes may insidiously take place, and the person is then unable to stop, i.e. they’re addicted. It then becomes a tug-of-war between the central, emotional brain and the cortical, rational brain. Environmental triggers trip this comfort eating need (background stress is pretty much always there), as well as acute emotional distress itself.
The Yale researchers have come to suspect that environmental triggers have an effect on some people that is not only psychological but physiological. Advertisements are a prime example. For a food addict, a picture of delicious-looking food can cause changes in the body’s chemistry, just as erotic visuals can cause certain other changes. If this is so, it might help activists who work to ban the most blatant kinds of exploitative advertising, and would like to ditch all of it. Gearhardt compared certain kinds of hedonic, hyperpalatable processed foods to cocaine, saying, “These are foods that really can sort of hijack our brains.”
But mysteries still remain. Weir finishes up,
Although the study highlights the physiological nature of food addiction, Gearhardt said it’s still unknown whether people are born with a predilection for food addiction or develop it through their behavior.
You will remember Jennifer LaRue Huget, a former non-believer in the concept of food addiction who was influenced to reconsider her position by Michael Prager. She writes for the The Washington Post about all aspects of health in a column called “The Checkup.” In the column, Huget elucidated one of the reasons why this kind of research is important, which we have also talked about: the future status of food addiction in the pages of the Diagnostic and Statistical Manual of Mental Disorders (DSM). As she points out, substance dependence is defined by a set of criteria in the case of alcohol and hard drugs, but not clearly delineated in the case of food. Huget reveals a detail of the experimental setup:
Gearhardt and her team used functional MRI to record brain activity as the women were shown images of yummy chocolate shakes and of a clear, taste-free solution. MRI images were also recorded while the women actually sampled those beverages. (The study explains that the clear formula was made to replicate saliva, as the taste of water actually triggers activity in some brain receptors.)
Yuck! Did the participants know they were offered imitation spit? That would certainly be a buzzkill.
For Healthland, Maia Szalavitz explains a lot about how the brain works in this situation and reminds us that addictions are not simple, because they involve so many human factors, which may be much more relevant than the substances themselves. Szalavitz asks,
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.
Jaya Saxena on Gothamist entitled her story “Study: Chocoholism Is Actually A Disease,” in which she remarked, “Unfortunately, like alcoholism, this is probably another disease you can get yelled at for having.”
Your responses and feedback are welcome!
Source: “Yale Study – Some people suffer from ‘food addiction’,” Healthy Living, 04/05/11
Source: “Study explores link between food, drug addictions in brain,” Columbia Daily Tribune, 04/10/11
Source: “Yale study probes food addiction,” The Washington Post, 04/05/11
Source: “Heroin vs. Häagen-Dazs: What Food Addiction Looks Like in the Brain,” Healthland (TIME), 04/04/11
Source: “Study: Chocoholism Is Actually A Disease,” Gothamist, 04/05/11
Image by theimpulsivebuy, used under its Creative Commons license.