I caught this article on ScienceDaily about the work of Professor Bart Hoebel at Princeton who has been attempting to show that sugar is an addictive substance like a drug. He presents data at the American College of Neuropsychopharmacology meeting to suggest that sugar fulfills the criterion for substances that we traditionally define as addictive:
Professor Bart Hoebel and his team in the Department of Psychology and the Princeton Neuroscience Institute have been studying signs of sugar addiction in rats for years. Until now, the rats under study have met two of the three elements of addiction. They have demonstrated a behavioral pattern of increased intake and then showed signs of withdrawal. His current experiments captured craving and relapse to complete the picture.
"If bingeing on sugar is really a form of addiction, there should be long-lasting effects in the brains of sugar addicts," Hoebel said. "Craving and relapse are critical components of addiction, and we have been able to demonstrate these behaviors in sugar-bingeing rats in a number of ways."
(If you want a simplified description of the work, read the article on ScienceDaily. For those who want a more sophisticated explication, read this recent review by Hoebel and others.)
What I want to talk about today is how I have a problem with the statement, "sugar is like a drug." In order to explain why, we have to take a little digression into how neuroscientists define and test addictive substances.
In general, as neuroscientists we have four general criteria for an addictive substance:
- Bingeing: When you have a substance, it makes you feel good so you take a lot of it.
- Withdrawal: Discontinuation of the substance causes the opposite effect of bingeing. When you don't have it, you feel worse than normal.
- Craving: When you don't have the substance, you want it more and you will do more to get it. We say that the motivation to get it is greater.
- Sensitization: When you are addicted, you are more sensitive to the effects of the substance. Less of the substance causes greater effects.
We use these criteria to test whether substances are addictive in animal models. For example, say with drug X, I put in the rats water and suddenly the rat is drinking a lot of water (bingeing). I take it out of the water, and the rat sits there doing nothing for hours. It's activity is less than average; it is less likely to indulge in novelty-seeking (a very rat-like behavior) (withdrawal). If you make the rat work to get the drug, it will work harder. If it has to run up a ramp to get it, it will run faster and farther (craving). When you give the drug back, it takes much less to get the rat back to baseline behavior (sensitization).
The point of this description is that this is our operational definition of addiction. I have talked a lot on this blog that in order to make animal models for things like addiction behavioral neuroscientists have to operationalize behavior. Operationalizing is the process of changing an abstract description of a behavior like addiction into an experiment with clear numerical endpoints. In the paragraph above, I described how we might operationalize addiction for a rat animal model. It could include numerical endpoints like "how much water with drug X does the rat drink?", "how inactive is a rat in withdrawal -- as measured by distance moved over time?", or "how much work will the rat do to get the drug as measured by lever presses?".
These are the types of experiments that are done with all types of drugs in labs doing addiction research. Further, they have allowed us to identify a variety of molecular changes associated with addiction in various areas of the brain. Much of this research has focused on the dopamine-reward system in the brain, and it has focused on brain areas like the nucleus accumbens. We think that drugs cause -- in some cases irreversible -- molecular changes to the reward system. We believe these changes cause people to behave the way they do when they are addicted.
Now from the article and what I have read about Hoebel's research, I can conclude that he has evidence that sugar as a substance meets the operational criteria listed above for addiction. Further, he also has biochemical evidence that sugar causes similar changes to the reward system as drugs like cocaine. Good and fine. I have no reason to doubt either the veracity or the relevance of these findings. Indeed this how we have been studying addiction for over a decade.
What causes me to raise an eyebrow at the statement "sugar is like a drug" is three things. First, the statements that I have read say nothing about the relative addictiveness of sugar as opposed to other drugs. Second, mechanistically I think there are fundamental differences between sugar and other drugs. Third, I have a metaphysical problem with interpreting the outcomes of behavioral experiments as evidence for the similarity of drugs and sugar.
1) Some news articles in reference to this research that say that "sugar as addictive as a drug." This is not accurate. Sugar is addictive as a drug in the sense that they appear to use similar mechanisms, but this has nothing to do with the degree of addictiveness.
Sugar may be mechanistically similar to crack in terms of addictiveness, but I have never heard of someone stealing a car radio to get a Twinkie. It is likely that the quantity of drug required to get "addicted" to sugar is quite much higher. It is likely that "withdrawal" from sugar shows a statistically significant behavioral change in rats, but nothing like the withdrawal from cocaine.
So saying that something has a similar mechanism says nothing about the relative addictiveness of substances.
2) I am suspicious that drugs and of sugar have exactly the same mechanism of addiction. Let me make something clear, I do not dispute the data with respect to the biochemical changes in the brain associated with sugar addiction. Sugar causes pleasure; repeatedly pleasures potentiate the dopamine reward system. I get that.
But there are some drugs out there which cut the middleman out. There are some drugs -- drugs like heroin -- that go directly into the nucleus accumbens and potentiate the reward system. Whereas sugar -- it would appear -- has to activate the perceptual system in order to change the reward system. You have to taste the sugar and like it in order for it to change your brain. (I may be wrong about this. For instance, there may be direct affects of high doses of sugar on the nucleus accumbens that I don't know about. But from what I know that isn't the case.)
There is a difference in mechanism between a substance that targets certain receptors in the brain directly, and one that influences the activity of those receptors through the taste system. Further, this probably explains the difference in addictiveness between sugar and say crack. When you cut out the middleman, you can have much more serious effects.
So saying that "sugar is like a drug" in terms of mechanism is not entirely accurate. Some of the same systems are activated, but the mechanism of this activation is slightly different.
3) I have a metaphysical point to make: operational definitions of behaviors in terms of experiment do not always capture all there is in a behavior. For example, one of the problems that you have with addiction is that there is physical dependence and psychological dependence. The experiments I described above probably do a damn good job describing physical dependence, but what do they do to describe psychological dependence?
The assumption of behavioral experiments is that when the rat is willing to do more to get something, it's motivation -- in the psychological sense of the word -- is greater. But we don't have much of a glimpse into the interior life of rats do we? It is kind of hard to tell whether a rat is working harder for a drug because it likes it or because it fears withdrawal or some combination of the two.
Maybe, this is just a problem that I have with the whole idea of behaviorism. (Incidentally, Hoebel studied under Skinner as an undergrad.) Cognitive variables that often cannot be directly observed experimentally -- unless you are really, really clever -- affect experimental endpoints. For example, learning is fundamentally a cognitive variable that changes over time that you can't see unless you have the right experiment to measure improved performance. With respect to addiction or really anything else, it is impossible to know whether our experiments for addiction have failed to capture some important cognitive variable like psychological dependence.
(I know that someone in the comments is going to call me out on my insufficient appreciation of Skinner's profound genius. Just to get ahead of your comments: A) I know more about him than you think, and B) Tolman was ultimately more right than Skinner. So if you want to get in a historical debate about the significance of behaviorism, save it. Debates about the significance of behaviorism are a lot like debates about the humoral theory or the Aristotelian universe: tedious to anyone who isn't a true believer.)
My point here is that you say can "sugar is addictive like a drug," but what really matters is what you mean by like. It is like a drug in the sense that it and cocaine produce similar data in experiments with rats. But is it like cocaine in the sense that the perceptual experience of the two are similar? I like sugar as much as the next guy, but I assert that an all-night coke jag is a bit different than staying in with a pint of Haagen Dazs.
The purpose of my exercise here is that you might understand how we define addiction in the laboratory and hence understand why a researcher would say that sugar is like a drug. I believe Hoebel's results, and I think that they are significant in understanding diseases like eating disorders or obesity. However, saying that sugar is a drug is not the whole story, and I think people need to recognize that.
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Brain reward systems evolved to reinforce eating and sex, which ensure survival. Drugs usurp these brain pathways and promote addiction. It is more accurate to say that drugs are like sugar, only more powerful.
I have never heard of someone stealing a car radio to get a Twinkie
But you don't have to do that to get sugar. Heroin/cocaine are hundreds of times more expensive. Sugar is far, far easier to obtain, so extreme behavior isn't necessary. They're not really comparable.
"I like sugar as much as the next guy, but I assert that an all-night coke jag is a bit different than staying in with a pint of Haagen Dazs."
I sure hope so, because I've done the latter more than once! (Although I usually end up getting high off Ben and Jerry's.)
Seriously - nice post.
Nice post!
You could also make the argument that, yes, some types of natural substances (such as sugar and fat) are addictive, but perhaps they are SUPPOSED to be. After all, if we didn't feel completely awful when we were starving, there wouldn't be a lot of incentive to eat and keep ourselves alive. The point of a "reward" system (in a highly anthropomorphic sense) is the keep us doing what we've doing to keep the species going. We're supposed to really like food, and we're supposed to really like sex. It's when we use drugs that highjack this system that we run into problems. Drugs such as cocaine and heroin provide a high, but they don't provide substance, there is no caloric content and they don't promote reproduction or do other things that are generally considered to be 'good' for you.
High calorie foods have always been found to be reinforcing in animal paradigms, and food deprived animals will of course work very hard for a sugar pellet or some peanut butter. But I fail to see how this is a bad thing, unless of course you are talking about the context in which we have too much access, leading to overeating and obesity. I think the studies on sugar are interesting, but I think a reaction of "OMG SUGAR IS EVIL" is a more than a bit extreme.
Eating concentrated sugar gives you a quick burst of energy, it is psychoactive. If I'm remembering correctly, rats will consume sugar as Hoebel describes even without the sense of taste.
Many wars have been fought over access to sugar and sugar cane plantations (in Jamaica, Cuba, etc).
Consuming coca leaves by chewing or as a tea is very popular and completely legal in some (all?) parts of S. America. Maybe this is similar to eating fruit rather than refined sugar.
Saying that sucrose is not a drug is like saying that C02 is not an air pollutant. There should be more of an open discussion around definitions and regulations of personal use of drugs.
IMO, the current drug regime is unethical and not based on science and reason. Psychedelic drugs like LSD, psilocybin, and mescaline (peyote) are not addictive or physically harmful and are used but many people for spiritual/personal purposes. In fact, mescaline is used legally in religious ceremonies in the US by approx 250,000 members of the Native American Church. Yet thousands of people are now serving excessive prison sentences for LSD et al.
Try to stop self-administration of refined sugar for one week. Many people are more addicted to the sugar in their morning coffee than the caffine. Sugar addiction is likely responsible for much of the increase in obesity and diabetes. It is reasonable to increase public awareness and consider regulation of sugar, for instance efforts to limit sugar-products in schools and childrens' foods.
This study is a good example of why we need to stop outlawing drugs. Why should I as a tax payer have to pay taxes towards people that use refine sugar that are overweight or have diabetes? People choose there life styles and should have the right to do so. But for me to have to pay for the health cost that refine sugar causes is wrong. Same as me having to pay taxes for something that people do in their own home. If people want to use drugs in their own home let theme. But for me to pay the legal bill for a bunch of white "Moral Majority Christian" that are toting "zero tolerance" when they are the filthy ones-ie Bankers, Enron, Murdock ect.. is driving America into the ground.
I enjoyed reading your post, but I think you are splitting hairs. Your argument seems to be that sugar meets the "operational" definition of an addictive substance, but that it lacks an adequate behavioral component to be characterized as "addictive" -- or at least that sugar is not "as addictive" as a given drug. I disagree.
You said, "Sugar may be mechanistically similar to crack in terms of addictiveness, but I have never heard of someone stealing a car radio to get a Twinkie." I agree. However, I've never heard of someone stealing a car radio to get cigarettes, either. Would you argue that nicotine is not addictive?
You said, "So saying that something has a similar mechanism says nothing about the relative addictiveness of substances." Is there a scientifically valid method for measuring the relative addictiveness of different substances? If so, I have not heard of this. You would do your readers a great service by pointing us toward this research. Personally, I don't think that relative addictiveness is an issue. As a nurse, when I measure pain in a patient, I use a subjective pain scale of 0-10, based on the individual's personal experience. (In other words, your definition of 5/10 pain is not the same as mine. And neither is more "valid" than the other.) I believe the same is true of addiction. One person might be able to kick methamphetamine relatively easily while another may never be able to stop using it. The same person who kicked meth may never be able to stop using nicotine. Does this say anything about the relative addictiveness of these two substances? I don't think so.
You said, "I like sugar as much as the next guy, but I assert that an all-night coke jag is a bit different than staying in with a pint of Haagen Dazs." I think this illustrates that you have never known a person with a serious eating disorder or food addiction. I can assure you the shame of spending a night with a pint (or quart) of Haagen Dazs, and the insatiable craving that accompanies it, are no different from the feelings of the shame-filled crack addict who tearfully promises his/her family s/he will quit the habit the next day. In my experience, addiction is addiction is addiction.
So what's my point? Do I believe sugar should be outlawed? Absolutely not. However, I do believe it's important for people to understand that sugar has a physically addictive property, as compared to other foods that do not. This new research gives people interested in nutrition more information about how to handle sugar in their diets. Perhaps this study will help people make better choices regarding how much sugar they (and especially their children) consume. Hair-splitting aside, I don't think that's a bad thing.
BudgetBanquerts has a great letter.
My understanding of refined sugar is that it goes to a gland. It "whips" that gland into action-your engery-. Refine sugar has zero nutrients-value. Indeed, the nutrients are processed out in the refinement. So it literally takes vitamins out of your system, by giving the body a empty high.
Make sugar illegal and I'm sure you'll find all sorts of illegal behaviour erupt. Smuggling, boot leg production, corruption and all the rest. The potency of sugar is also related to the number of your receptors. This differs from individual to individual. And as a cheap pervasive drug sugar is quite potent.
This was a horrible post. All of you're points were invalid. What on earth are you trying to prove to yourself/ the world? I guess what pisses me off is that you act like an expert on the subject and that your word is final. You're title "Sugar an Addictive Drug? Eh Sort Of" suggests that you've proven something when in fact, ALL OF YOUR POINTS ARE WRONG!
The stigma associated with crack and cocaine but not with sugar seems unreasonable to me, because the number of people who die from diabetes is far greater that the number of people who die from drug overdoses.
First, the fact that sugar is less addictive than crack doesn't in any way make it not addictive, or not a drug. Crack is an extremely addictive and dangerous drug, there are also many minerly addictive drugs such as caffeine. The relativity of addictiveness of sugar to other drugs does not keep it from being an addictive drug. As you say it is mechanistically the same as an addictive substance. It is not much less addictive than caffeine, an addictive substance. I bet you're the kind of person who thinks marijuana is an addictive drug (correct me if I'm wrong).
Your second point that the mechanism of sugar addiction is different from all other drugs is wrong. Have you ever heard of a "sugar rush"? Herbal sweeteners do stave off sugar cravings, and leaves a sugar addict feeling empty. Don't assume that the sensation of sweetness is responsible for our addiction to sugar.
Your third *Cough* metaphysical point is one I feel does not even belong in this discussion. We do not have much insight into the life of rats. However, WE ARE NOT RATS! Human's do seem to have psychological dependence on sugar the exact way we do with caffeine or any other addictive substance. What you need to do to prove this point is show that sugar lacks a psychological addiction that all other addictive substances have, not show how one study about rats didn't delve into the psychological aspect of their dependency, and then assume that there was some sort of psychological dependence with rats given cocaine that did not exist when the rats had sugar. Try to leave out metaphysics from your arguments in the future. I feel like a lot of the time you are trying to answer the question "Is sugar exactly like cocaine" instead of "Is sugar an addictive drug" like your thesis suggests.
Sorry for sounding so condescending, you're probably a nice person and all. To me this seems like you trying to defend you're sugar habit in face of this study. And sure, I'd rather you have sugar habit and a cocaine habit, but you need to recognize that sugar is one of the most widely used and abused drugs.
p.s.One criticism people may have with this comment is that my earlier comparison of drug overdoses with diabetes deaths assumes that all diabetes deaths are caused by sugar. I do not assume that, although a great percentage probably are.
1. sugar may not be proven in studies to show all four elelments of being an addictive substance- but ask any obese person with a sugar addiction if he/she has ever felt craving and sensitization- all you need to do is talk to sometone like this who wil readliy say that they suffer from all four. so yes, it IS addictive.
2. sugar is cheaper and more readily avalailable than cocaine or herion, thus no need to pinch radios. additionaly, sugar is glorified everywhere (just turn on the telly to see thousands of ads about icecreams, twinkies, cadbury, pasta...) but heroin is socially unacceptable with users considered dirty or diseased, so naturally drugs will be dearer and harder to get.
3. people say that the trouble with other drugs is that they cause a person to become debilitated- ie. heroin users find it hard to ufunction in society. however, morbidly obese people are debilitated by their weight and health problems, shunned by society, and will die young. seems to me that sugar IS an addictive substance- but its effects over time are subtle, with diabetic onset occuring with weight gain.
4. there is the behavioural aspect of addiciton- scientists are saying that its not possible to fully say that sugar is physically addicitve because the psychological dependence on food is difficult to separate from physical dependence. Are they then implying that other durgs that are addictive do not have ppyschological dependence also? For example, the street kid who is raped uses drugs to forget the pain of life.... the fat person uses food to forget about their lack of self control and self esteem issues.
hmm. tricky.
..."staying in with a pint of Haagan Daz"... I am a sugar addict. I had to laugh right out loud about that comment. A pint of ice cream is but an appetizer compared to reality. Ice cream might start out tasting good, but after the first cup or so, you really stop tasting anything because of frozen tongue or "satiated" taste buds. That doesn't stop me from continuing to eat it because my brain wants more and more even when I can logically be telling myself to stop. I have eaten a half gallon in one sitting because of the rush of sugar and not wanting it to stop. Even more likely to happen was that I would "graze" on sugar. I would eat enough to get the rush I was looking for, then wait until the "high" started to wear off, and repeated the entire process all night.
In some ways the brain responds similar to cocaine, but in many ways being a sugar addict is even more similar to alcohol addiction-legal, readily available, often used to cope with social situations and to escape emotional pain.
The alcohol in drinks breaks down into sugars. Many alcoholics remain sober from alcohol, only to find themselves at the doors of Overeaters Anonymous because they switched addictions to sugar.