Not exactly, but an article on Health.com from a year ago that was picked up by CNN highlights perfectly the media’s insistence on exaggerating the findings in medical studies beyond all reason when the potential to scare people or stir up controversy exists.
First, note the difference between the original headline and the one on CNN. The first is “Do Fatty Foods Act Like Cocaine in the Brain?” That’s technically a little foolish, since foods don’t penetrate the brain, but it’s close enough. CNN decided that headline wasn’t wowsy enough, so some creative clown there went with “Fatty foods may cause cocaine-like addiction,” which is not even close to the same thing. My mock post title is closer in meaning to CNN’s than CNN’s is to the one at Health.com.
As far as the content is concerned, read the abstract of the study itself first (the full text costs money). In everyday terms, the article explains that fat rats given as much “palatable” food as they wanted demonstrated a down-regulation of certain dopamine receptors in the brain, whereas thin rats did not. What this means is that fat rats, having scanty dopamine receptors, were essentially unable to derive the same satisfaction from a given amount tasty food as lean rats were, presumably because they needed to release more of the pleasure-associated neurotransmitter dopamine to achieve a given effect. In a nutshell, they developed tolerance to tasty food at the neurophysiological level. What is unclear, at least from the abstract, is whether the down-regulation was inherent in some rats and made them more susceptible to overeating, or whether some other factor inspired the rats to overeat and the down-regulation was a consequence of overeating rather than a cause. It could be both. The distinction is important, because if the findings in these rats are applicable to humans in meaningful ways — and that is always a huge leap of faith — it suggests that some people are more apt to become “hooked on” fattening foods, just as some are more apt to abuse chemicals that others can use in moderation.
The Health.com article sheds some light on the mystery. It states that the study found that “[w]hen rats consume these foods in great enough quantities, it leads to compulsive eating habits that resemble drug addiction.” In other words, too much “junk” food, as the article calls it, leads to a craving for more of the same food, whereas a modest amount does not. Perhaps this is what the researchers found (see below), but it makes little sense in the light of physical addiction. Those people who are genetically susceptible to alcoholism, for example, don’t become alcoholics by outdrinking others in the absence of already wanting to do so. And opioids such as heroin, given in sufficient amounts, will make anyone physically addicted apart from the pleasure and reward aspect. But the article putting things the way it does essentially tells people that if they eat certain things above a certain threshold, then they’ll suddenly become addicted to them and have to eat a ton of it. Maybe such a positive-feedback mechanism exists, but there’s no evidence to suggest it and the writer is merely capitalizing on the fear factor here.
The article also says, “Kenny and his co-author studied three groups of lab rats for 40 days. One of the groups was fed regular rat food. A second was fed bacon, sausage, cheesecake, frosting, and other fattening, high-calorie foods—but only for one hour each day. The third group was allowed to pig out on the unhealthy foods for up to 23 hours a day. Not surprisingly, the rats that gorged themselves on the human food quickly became obese.” Compare this to the study abstract, which says “we detected compulsive-like feeding behavior in obese but not lean rats, measured as palatable food consumption that was resistant to disruption by an aversive conditioned stimulus.” I wish I could tell how the rats who were exposed to fatty foods for just an hour (which is still plenty) were distinguished from those who were exposed to it for 23 hours a day. I suspect that the groups were matched controls and that more exposure turned the same rats into heavier rats, but the wording of the abstract doesn’t make this clear.
In any event, the lesson here, if there is one (besides not writing long blog posts in the absence of being able to read the full texts of studies), is that it’s senseless to compare drug addiction to food “addiction.” People don’t undergo dangerous or uncomfortable withdrawal from cake or ice cream. Wanting these foods, however strongly, is different. (In this way food is more like cocaine — the physical withdrawal from which is not as disruptive as that from other drugs — than like heroin or alcohol.) Then there’s the difference between the higher thought-processing centers of rats and those of people; I cannot imagine even the most ravenous gourmand devouring Twinkies and the like even when given electrical shocks whenever he throws one down the hatch. The Dr. Wang quoted in the article urges caution in some of these areas, but the framing of the piece tends to quietly shout him down.
This is simply one more case of scientists uncovering the molecular underpinnings of something that has been known at a real-world level for some time (which is interesting) and the media doing its best to mislead people about it. Most people can consume “junk” food without needing to keep doing it. A critical factor separating us from rats is that we (some of us, in some ways, at least) care about our health. Rats don’t give a fuck how fat they get or how long they live. They don’t even have a way to conceptualize such ideas. That doesn’t mean that the neurochemistry described in the study isn’t relevant, but this “addiction-as-obligatory-effect” bullshit ought to be thrown out, as it fuels stupid decisions like this one. If it made sense to ban the use of anything that some people would wind up using to excess, and to their own detriment, then we might as well go ahead and make video games, Internet surfing, non-procreative sex, and a host of other things illegal along with drugs and gambling. And come to think of it, I shouldn’t give the religious wrong any more ideas, given that they’ve long had their jaundiced eyes on the sex angle.