Obesity, drug addiction, and dopamine

Eating junk-food can be addictive, and apparently, it causes brain changes that look eerily similar to drug addiction. That’s the message not only from the rapidly fattening waistlines of Americans everywhere, but also from the Johnson and Kenny labs at the Scripps Institute.

Food and drug addiction

The idea that obesity is caused by a compulsive pattern of eating, and that there could be a similarity between such compulsive eating and drug addiction isn’t super new. In fact, Dr. Volkow from NIDA seemed to make research into this association her goal when taking  the helm of the addiction research kingdom.

When you think about it, the notion isn’t far-fetched: Drug addicts continue to take drugs, in increasing amounts, even though they’d often like to stop (at some point) and in the face of negative consequences and the common loss of other important life functions (like family, work, etc.). Obese individuals are quite the same, eating more and more food regardless of their desire to adopt a healthier diet and in-spite of ridicule, low self-esteem, and decreased functioning that often accompanies extreme weight gain.

The research by Johnson and Kenny examined whether exposure to the kind of high-fat, super high-calorie foods that floods the junk-food market are responsible for creating food-addicts in a similar way to drugs that alter the brain in ways that make stopping more difficult.

Dopamine, reward, and junk-food

The study took three groups of rats and gave them either the regular chow diet lab animals are used to or the worse kind of birthday party food: bacon, sausage, cheesecake, pound cake, frosting and chocolate. You can imagine the party going on in the rat cages that got to eat that! Of the two groups that got to eat the crazy-fat food, one had unlimited access while the other got to binge for only one hour a day.

The bottom line: Only the rats that got unlimited access to the fat-party food developed compulsive eating habits that resulted in roughly twice the weight gain of the other two groups and the ability to continue eating even in the face of signals for punishment (a light that they were trained to associate with shocks).

When the researchers looked deeper, they found that the brains of these rats suffered a significant reduction in the density of a specific kind of dopamine receptor (D2) in a brain part known as the striatum, the same kind of reduction common in drug addicted people and obese individuals. This receptor type is often thought to be important for regulation of impulses, both physical and otherwise. It therefore makes sense that losing this type of function would cause uncontrollable eating or drug taking.

Are drug- and food-addictions the same?

While this research isn’t saying that compulsive eating, or obesity, are the same as drug addiction, it does strongly suggest that there are common mechanisms in both. More importantly, it reveals a common process that unfolds when over-exposure to the reward, in this case food, occurs. This tells us that there can likely be common pathways to these different addictive disorders, though whether any specific person ended up a food- or drug-addict because of this kind of process is still an open question. I wonder if we’ll see something like this with sex addiction soon…


Johnson and Kenny (2010) Dopamine D2 receptors in addiction-like reward dysfunction and compulsive eating in obese rats. Nature neuroscience, 13, 635-641.

How can I overcome all this sugar??? The dilemma of food addiction

I’ve been asked by several people about the impact of sugar addiction and the possible ways for overcoming it.More cake please

The dilema of food addiction

Food addiction is especially difficult to fight because unlike drug addiction, you can’t simply stop eating, regardless of your willpower. This means that a person addicted to highly sweetened foods needs to figure out a way to continue eating without indulging in their favorite foods. This is a bit like telling an alcoholic they can only drink beer but not liquer, or telling a cocaine addict they can only smoke a little bit of crack every day…

My sugar addiction story

While there is very little research that I’m aware of regarding food addiction, I can share with you my story.

I’ve always been a huge fan of sugar. I love chocolate, soda, and ice-cream, and anything else that is loaded with sugar.
The soda habit I made myself quit a few years ago when I was trying to lose some weight and had started working out. I was very determined and when I realized just how many calories are in each can of soda, I told myself that I needed to reduce how much of it I drank. At the time, I would easily have 3-4 cans per day, and while I wasn’t able to completely cut soda out, I went down to 1 or less every day pretty quickly. My trick at the time was to remind myself that all that work I just did at the gym would easily be erased by having a single can of coke (my weakness).
Still, I was eating a lot of other stuff that was pretty bad for me, mostly without even realizing it.

It was only last year, possibly because of reading the article I’d talked about in my post about sugar addiction that I started really looking at what I was eating. It didn’t hurt that my girlfriend at the time was a health nut. I’d heard about the evils of High fructose corn syrup (HFC) before, but after reading the research, I realized that the stuff is perfectly engineered to make my body crave more and more sugar.

I’d already kicked drug use years ago; I wasn’t about to let sugar control me now…

When I started reading the labels of products, I was amazed. HFC is in almost everything!!! I was discovering that the bread I was eating, some of the deli meets I was putting on it, and nearly every drink I was having included the stuff. Without ever realizing, and with the wonderful help of the food manufacturing sector, I had become essentially dependent on this stuff. There is research that indicates that the make-up of HFC, which is a bit different than that of natural sugars, may contribute to obesity and cardiovascular disease. This evidence is not conclusive as of yet, but again, there’s also research that foods loaded with sweeteners in general can cause consumption patterns very similar to addiction.

My addiction advice

Thankfully, the are products who don’t contain HFC, and I’ve been doing my best over the last year to replace my old food choices with those.
Just to be clear, I still consume more sugar that I probably should. However, I feel that by removing this highly sweetened chemical from my diet, I am essentially allowing my body to now process the more natural sugars I’m consuming. In the long run, I’m hoping that this switch will work to reduce my overall dependence on sugar.

So, my advice, given the fact that we all need to continue eating:

Don’t try to remove sugar from your diet, especially because the artifical sweeteners have themselves been shown to produce consumption patterns that are unhealthy (at least in animals for now). Instead, start becoming aware of what you are putting in your body and reducing the consumption of sugar that way.

Most natural unprocessed sugar products have lower sucrose and fructose concentrations simply because they are not as heavily processed to remove impurities. Switching at least some of your consumption to these types of sugar will reduce at least some of your sugar intake without leaving you feeling like you had to make any major changes.

Goals are good as well. If you’re eating like I used to, you put 2-3 spoons of sugar in your coffee every morning; try reducing the amount of sugar you’re adding to foods by a small percentage (like 10-15%). Such a reduction won’t massively alter the taste of your foods but will get you on your way…

Question of the day:
Would you like to share your story of overcoming, or struggling with, addiction to sugary foods?
I’m sure all the readers will benefit from hearing others’ stories.

Give me SUGAR!!!! And a little food addiction on the side…

sugarSo while we’re sitting here talking about drug addiction, quite a bit of research in the last few years has looked into food, and specifically high-sugar-content foods, as a possibly addictive substance (food addiction).

The focus started when the new head of NIDA (The National Institute on Drug Abuse), Dr. Nora Volkow, who’s been doing research on obesity, took her seat a few years back. Since then, there have been quite a few papers showing that when given foods (or water) high in sugar content, animals develop behavioral patterns that are very similar to drug addiction.

This makes sense from an evolutionary stand point, since sugar gives our bodies carbs, which supply energy for our daily activities. However, it’s probably no secret that 50,000 (or even 1000) years ago, people weren’t consuming foods with refined sugars crammed into them (refined sugars have only been around for about 250 years). Back then, people needed all the energy they could get their hands on.

Unfortunately for us, evolution doesn’t move as quickly as our industrial and technological advances, which means we now get more of the high energy foods more easily, all while moving less and therefore putting out less energy.

The result? Atkins diets and the likes recommending low carb intake, which in actuality, should probably read “sufficient carb intake.”

A very recent paper has shown that even artificial sweeteners (specifically saccharin, see citation), may be able to induce these types of behaviors. In fact, saccharin sweetened water (and also sugar sweetened water) was chosen over cocaine, even for animals that already liked cocaine, and even when they were offered more and more cocaine!!! How’s that for amazing?!

What does this mean for food addiction?

Well for one thing, it means that if we want to battle the obesity problem in this country, we need to re-examine the availability of these high-sugar, high-calorie foods. But, it may also mean that low calorie foods that are artificially sweetened may soon be shown to be as bad for us…

I’m telling you, by the end of all of this, we’ll learn that growing your own vegetables and fruits is the only way to stay healthy. Come to think of it, even then, I know at least one person who may be addicted to fruits…

Question of the day:
Does your experience with high-sugar foods lead you to agree or disagree with these research findings???

Magalie Lenoir., Fuschia Serre., Lauriane Cantin, Serge H. Ahmed (2007). Intense Sweetness Surpasses Cocaine Reward. PLoS ONE 2(8): e698.

More CPDD Addiction research: Addiction, exercise, recovery!

Okay, this is probably the last addiction research update I will give focusing on the Reno conference. The rest of the stuff I learned will be incorporated into future posts.

I’ve written before about the relationship between exercise and recovery (see here) and I will surely write more since for me, it was a big part of the equation.

two separate studies at CPDD reaffirmed my belief that exercise can be a very useful tool in addiction recovery.

The first study, conducted in humans, examined the effect of incorporating an extensive exercise routine into a residential, as well as intensive outpatient, addiction treatment program. Their findings showed improved outcomes for participants in the short, as well as long run. These included length of sobriety, subjective assessment of well being, and more. In talking to the researcher, she seemed to believe that at least part of the effect was due to the relief of cravings achieved by allowing patients to focus on something that took effort, rather than simply sitting around.

The second, and to my mind even more interesting, study examined the effect of exercise on cocaine self-administration in rats. Researchers assigned half of their rats to a cage that had a running wheel while the others were assigned to a regular cage. the rats with the running wheel used the device to run an average of 12 kilometers a day! After a week of simply resting in their cages, when transferred to another cage for 2 hours a day, the rats who had the wheel in their cage took less than half as much cocaine as the rats who didn’t have a wheel. the “wheel-rats” were also found to run less after they began the cocaine portion of the experiment, but their cocaine-taking never got near that of the non-exercising rats. It seems that having the exercise did something to reduce the reinforcing power of cocaine.

I have a feeling that future research will show that these finding hold true for other drugs (like crystal meth, heroin, marijuana, cigarettes, and alcohol) and possibly even for behavioral addictions like food addiction, gambling, and sex addiction.

All in all, research seems to be supporting the notion that exercise can play a significant role in recovery from addiction. Whether it be for boredom relief or an actual internal change in the motivating power of drugs, it looks to me as if Addiction + Exercise = Recovery !

About addiction: Animal research, food addiction, policy, and cocaine addiction

Here are this weeks gems when it comes to learning about addiction. As usual, if you click this title’s post, you’ll get a list of our related post as a bonus!

Adventures in Ethics and Science A nice post about the current state of the animal-rights dialog

Addiction InboxMood Foods (and their possible role in food addiction)

Addiction TomorrowAdvocacy and Treatment

PhysOrgAltered reward-based brain-activation in cocaine addiction