Food Addiction Part 1: The Science Behind the Syndrome

by Dr. Sara Gottfried, M.D.

Most of us have a wonderful relationship with food. Beyond eating for survival, we enjoy food in moderation and know that it brings us nutrition, joy, and health. For some people, though, food is an obsession that dominates their life. Food addiction—a cluster of chemical dependencies that leads to a loss of control over food—can wreak havoc. In many respects, the behavior of food addicts is similar to those who abuse drugs and alcohol, which makes it that much more dangerous, especially if left untreated.

Many of us joke that we’re “addicted” to certain foods, but for true food addicts, this is a daily reality. “Refined food addiction involves the compulsive pursuit of a mood change by engaging repeatedly in episodes of binge eating despite adverse consequences,” explains Kay Sheppard, author of Food Addiction: The Body Knows. “The brain and body of a food addict react differently to addictive foods due to an inherited predisposition to the disease of addiction. The term food addiction implies there is a biogenetic, physiological, biochemical condition of the body that creates craving for refined foods: carbohydrates, fats, and salt (1).

There is no single explanation for cravings and food addiction. Evidence shows that some food addicts experience physical craving; that is, a powerful desire for food that is physiologically-based, suggesting an internal chemical basis to the problem. At the same time, there are multiple types of physiological food addiction, just as there are different biochemical processes that create different types of food addictions. That means food addition cam have many layers and many sources.

Bingeing and Food Addiction: The Making of an Obsessed Eater

Food addicts have a greater predisposition to find pleasure in eating certain kinds of foods, even if indulging leads to negative consequences like weight gain or adverse physical reactions. Healthy food doesn’t solve the problem. If a food addict becomes fixated on it, they will eat too much.

We used to think this was a problem of willpower, but our understanding has changed as we’ve learned more about food addiction. We’ve come to realize that the power of a craving can completely overpower willpower or reason.

Researchers at Yale University have developed a way to classify human cases of food addiction using something called the “DSM-IV diagnostic criteria for substance dependence.” Evidence suggests that the Yale Food Addiction Scale(YFAS) has become a very valid source of measuring eating pathology—especially binge eating— and may be a useful tool to identify potential food addicts. Also, in a recent neuroimaging study, researchers also found that YFAS scores were directly related to neural activation in specific brain regions that play a role in the experience of craving—and that high scorers had activation patterns that directly correlated with a reduced ability to control their eating. This means YFAS can be a very useful tool for identifying eating patterns that resemble classic addiction and it reinforces the view that food addiction is a classifiable condition, it has clinical symptoms, and it has a behavior profile similar to conventional drug abuse disorders. These studies (including ones at Harvard, too) show that food addition is real and that we can take the best practices from drug addiction to help sufferers manage it (2),(3),(4),(5).

Is “Big Food” Out to Get You?

I believe corporate food production could be considered the “Big Tobacco” of the 21st Century. Companies like PepsiCo, Dole, Kraft, General Mills, and Nestle turn us into unwitting test subjects as they manipulate sugar, fat, flour and salt to make their food addictive and irresistible.

Modern foods are engineered to increase the likelihood that susceptible individuals will develop an addiction. It’s tough for even the most disciplined individual to avoid the temptation. Making food available everywhere, increasing portion sizes, enhancing the taste experience—these are all steps purposely designed by Big Food to hook us. The more intense our food experience becomes, the more we’ll consume and the greater the chance we’ll become addicted.

Former Food and Drug Administration commissioner Dr. Kessler coined the term “hyper palatable” for good reason. Research suggests that highly-palatable food that excessively pleases our taste buds are also uniquely fattening and addicting (6),(7). For those people who become addicted to these appetite-stimulating foods, this powerful reward-seeking behavior can overcome the body’s innate mechanisms to balance energy intake and expenditure (8).

Here’s the problem. Palatability powerfully re-enforces the behavior around consuming (9). It is overseen by the hedonic system in the brain, which is associated with the reward system. The reward system is what motivates us to eat and the hedonic system influences the amount eaten (10). The more palatable the food, the more that reward processing part of the hedonic system can be changed and compromised. When this happens, the amount of palatable food we eat often exceeds the amount we need to satisfy our energy needs and it sets us up to over consume. And it’s no great surprise to learn that the high sugar, fat, and salt goodies pedaled by Big Food have abuse potential similar to addictive drugs (11). Research has demonstrated that each of these nutrient elements affects specific neurotransmitter systems in the brain (12). If you mess with them in just the right way, you can create food addiction.

Brain and Hormone Causes of Cravings

Here’s the interesting part: Food changes the structure and function of your brain, especially if you’re vulnerable, as I am. Food addiction research shows that there are neurochemical similarities between substance dependence and binge eating of processed foods. Critical data on food addiction also suggest that certain foods, such as sugar and fat, initiates addictive mechanisms in the human body similar to drugs like heroin or crack. The commonalities between overeating and drug abuse shared similar neural and hormonal pathways, which helps explain why some people cannot stop eating, even though it’s damaging their health. I will write more about this topic in future blogs, particularly about the role of the corticotropin releasing factor, which signals the body to release cortisol.

Overeating: Brain Chemicals That Hijack the Controls

For many people, hyperpalatable foods may lead to binge eating behavior by overstimulating dopamine receptors in the brain. Foods that are dense in fat and sugar prompt the striatum to make endorphins, the "feel good" chemicals that can trigger binge eating. These foods also spark dopamine, which motivates feeding behavior, and the prefrontal cortex, which influences decision-making. In some people, the actions of endorphins, dopamine and other chemicals that regulate reward systems can overcome hormonal signals and conscious attempts to stop eating when full. A strong motivation to eat high-calorie foods wins out over the knowledge that what you’re eating is damaging your health.

Dopamine, a neurotransmitter, is a known link between food pleasure, obesity, and addiction. Like other pleasurable behaviors including sex and gambling, eating can trigger the release of dopamine. The chemical reward, in turn, increases the probability that the associated action will become habitual, thanks to positive reinforcement conditioning. If activated by overeating, neurochemical patterns can make feeding behavior hard to control. The modern food environment we live in today may raise dopamine just as high as drugs (13),(14).

The areas of the brain that is involved in pleasure and self-control relies on dopamine. In both drug addictions and obesity, dopamine D2 receptor reductions are lower. There is a theory that binge eaters overeat to increase the amount of dopamine in the brain (15). In many substance abusers, a low level of dopamine receptors, caused by genetics or behavior, means they have to seek more dopamine-inducing substances to reach the neurochemical reward level of enjoyment (16).

Bingeing stimulates a change in the dopamine area, and the brain creates the increased instinctual appetite for the same foods that created the change (the craving). Brain imaging research shows dopamine receptors “light up” in drug and food addicts when they were thinking about their food or drug of choice (17).

Leptin acts as an appetite inhibitor and promotes thermogenic metabolism. Leptin plays a pivotal role in the regulation of energy balance, including appetite and metabolism. Research has indicated that normal leptin production is critical for maintaining healthy energy balance and avoiding obesity (18). Additionally, fructose (which is everywhere in the food supply) blunts leptin signaling, promotes sensations of hunger, and creates a desire for consumption even if we don’t need the extra food energy. While glucose stimulates the release of insulin (which decreases the desire to eat), fructose is a very weak insulin stimulator. Consequently, when eaten in abundance, fructose can result in biological changes that promote overconsumption (19).

Studies demonstrate that obese individuals show an abnormally high level ofghrelin in the body experience extreme appetites (20). Chronic lack of sleep increases ghrelin, creating hunger when one does not need to eat. This is likely the reason why lack of sleep is so often associated with obesity.

We begin to secrete insulin just by thinking about food. Insulin preps the body that glucose is on the way, so the body begins craving glucose. The greater the insulin and blood sugar response, the more intensely we like the food in our mind. Insulin signaling is sensitive to dietary fat and sugar intake (21). Those with sugar and carbohydrate cravings tend to be insulin resistant. Insulin resistant individuals have elevated blood insulin levels that stimulate appetite and the drive to eat.

How to Overcome Food Addiction

We’ve talked about the science behind food addiction. What can we do to overcome it?

As a scientist I feel addiction is a biochemical problem. As a doctor who specializes in hormones and weight loss, I feel people can change their biochemistry and cravings through personalized, optimal nutrition. Put another way, you can manage your food addiction through resetting your biochemistry.

Not eating enough (dieting), unstable blood sugar, low functioning thyroid, food allergies, and amino acid and fatty acid deficiencies can all weaken neurotransmitter mechanisms and disrupt brain chemistry. Nutrition should contain sufficient essential fatty acids and amino acid precursors to build sufficient serotonin and dopamine, including phenylalanine and tyrosine. Plus, we know that serotonin inhibits food intake, particularly intake of carbohydrate.

One of my most challenging online clients, Phoebe (a 42-year-old freelance writer), struggles with binge eating. She joined my online detox earlier this year and told me the following during our first Q&A call:

“Dr. Sara, I’ve read and researched everything written about how to stop bingeing. If I could just take a bath, call a friend, or just let the craving pass, don’t you think I’D DO THAT?  If I could stop the tsunami that compels me to drown in a sea of brownie batter, I would. Why the heck can’t I stop eating?”

Phoebe explained to me that she can feel a binge coming on. She told me that she could feel her body craving food, especially if it was processed. Why? Because she kept feeding her body refined carbs and white wine. It created the perfect storm. Her hormones were in junkie mode and wanted their fix.

Addictions, including eating disorders, are multifactorial and need a multifactorial solution. The overwhelming desire for certain foods can be genetic, environmental, or most likely a combination of the two.   Nutritional therapy can be one of the most beneficial ways to win the war. We know that when you stop eating binge foods – particularly the processed foods that contain sugar, fat, and flour—you will dramatically reduce your cravings and addictive feelings.

Armed with knowledge about your biochemistry and how the food industry is working against you can help you smack down those addictive feelings and break the hold they have on you. It won’t be easy. You need to be diligent. However, it gets easier as your brain transmitters and hormones get reset.

Understand that as a food addict, the food you reach for is designed to lead you astray. Don't let it. Break the cycle. Understand that your addictive feelings are biochemical and you need to give your body a fighting chance. Diet adjustments can make you more resilient in the face of food seduction. Strengthen that muscle instead of relying on willpower, which doesn’t stand a chance against the addictive biochemistry of dopamine and its receptors.

You can definitely become stuck in an addicted/overeating cycle because of vulnerability to certain foods. If you think you might be one of those people, see if you have any of these symptoms.

  1. Food is all you think about.
  2. You want to stop—but you can't.
  3. You eat in secret, or lie about what you've eaten.
  4. You eat beyond the point of fullness.
  5. You are compelled to eat, especially certain foods.

One of my teachers is Pema Chodron, the Buddhist nun and granny to addicts worldwide. Pema says:

“Working with addictions is about… not just grabbing for something to fill up the space, not giving in to this impulse to feel okay and just to get comfortable as soon as possible. But when we instead experience the raw quality of the itch or pain of the wound and do not scratch it, we actually allow the wound to heal.”

I agree. Use your food addiction as an initiation; as an important message from your body that we want to decode. Start by creating the space between the craving to eat or binge—and the giving into it. That’s where the healing begins.

In my next blog, I’ll give you my best strategies to help you beat food addiction, including the foods and supplements I recommend to reset dopamine and serotonin levels naturally. I understand that food addiction is painful and I want to help. Most important, I know that you can beat it. Armed with information and a plan, we can beat food addiction together.

 

References

1.http://www.examiner.com/article/exclusive-interview-with-renowned-food-addiction-expert-kay-sheppard

Corwin R, Grigson P. (2009). Symposium overview--food addiction: factor or fiction?. J. Nutr., 139(3), 617-619.

Gearhardt A, White M, Potenza M. (2011). Binge eating disorder and food addiction. Curr Drug Abuse Rev, 4(3), 201-207.

Gearhardt A, Corbin W, Brownell K. (2009). Preliminary validation of the Yale food addiction scale. Appetite52(2) 430-436.

Davis C, Curtis C, Levitan R, et al. (2011). Evidence that 'food addiction' is a valid phenotype of obesity. Appetite57 (3), 711-717. 

6  Gearhardt A, Yokum S, Orr P, et al. (2011). Neural correlates of food addiction. Archives General Psychiatry68(8), 808-16.

Luttner M, Nestler E. (2009). Homeostatic and hedonic signals interact in the regulation of food intake. Journal Nutrition139(3), 629-32.

Avena N, Gold M. (2011). Variety and hyper palatability: Are they promoting addictive overeating? Am J Clin Nutr94(2), 367-368.

Mitra A, Gosnell B, Schioth, H,  (2010). Chronic sugar intake dampens feeding related activity of neurons synthesizing a satiety mediator, oxytocin. Peptides, 31(7), 1346-1352.

10 Olszewski P, Levine A. (2007). Central opiods and the consumption of sweet tastes: When reward outweighs homeostasis. Physiol Behav91(5), 506-12.

11 Gearhardt A, Davis C. (2011). The addiction potential of hyper palatable foods. Curr Drug Abuse Rev4(3):), 140-5.

12 Yarnell, S. Avena, N. Gold, M. (2013). Pharmacotherapies for overeating and obesity. J Genet Syndr Gene, (April 1;4(3):131).

13 Volkow N, Wang G, Fowler J, et al. (2008) Overlapping neuronal circuits in addiction and obesity: Evidence of systems pathology. Philos Trans R Soc Lond B Biol Sci. 363(1507),3191–3200)

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15 Volkow N, Wang G, Tomasi D, et al. (2013). Obesity and addiction: neurobiological overlaps. Obesity Rev, 14(1):2-18.

16 Wang G, Volkow N, Fowler J. (2002). The role of dopamine in motivation for food in humans: Implications for obesity, Expert Opinion Therapeutic Target, 6, 601-9.

17 Volkow N, Wise R. (2005) How can drug addiction help us understand obesity? Nature Neuroscience, 8(5), 555-560.

18 Bjorbaek, C. (2009) Central Leptin Receptor Action and Resistance in Obesity JInvestig Med, 57 (7) 789-794

19 Bocarsly M, Powell E, Avena N, et al. (2010). High fructose corn syrup causes characteristics of obesity in rats: increased body weight, body fat and triglyceride levels. Pharmacology, Biochemistry and Behavior97 (1) 101-106.

20 Daws L,  Avison M, Robertson S. (2011). Insulin signaling and addiction.Neuropharmacology, 61(7), 1123-8.

21 Gearhart A, Corbin W, Brownell K. (2009) Food addiction: An examination of the diagnostic criteria for dependence. Journal of Addiction Medicine, 3(1), 1-7