Food Addiction and Research

November 11, 2013 General Interest

A few weeks ago a wrote  a post on food addiction and mentioned that I was working on a blog post for The Academy of Nutrition and Dietetics blog. It came out last week and I wanted to re-post it here but with a couple of other thoughts.

One of the things I love most about my job is that I get to blend the science of food and nutrition with the art of working with people in the real world. It’s the careful balance of art and science that I found so gratifying. This relates to the topic of food addiction. In the real world, it can be a very heated and emotional discussion. I have seen ardent defenders and spirited critics of the concept as well as everything in between.

My purpose in writing this particular post was to review the actual research. I wanted to get clear and share what we know about food addiction via research, what we don’t know, and what we need future research to take us. This is different than the clinical hat I normally where because I only minimally address application side of things. So please keep that in mind, along with the fact that I had an EXTREMELY limited word count! In any case, I hope that it’s informative and I hope we can all keep an open mind to such a complex topic. The original version was posted here but I have pasted it below. I’d love to hear your thoughts and comments.

I’m a chocoholic. I’m addicted to sugar. Once I start eating chips and salsa, I can’t stop.

How many times have you heard these and similar sentiments? If you’re like me, then you’ve heard them a lot! But over the past several years these sayings haven’t only been used casually, but also seriously considered in scientific circles. With the rise of obesity and the DSM-V’s (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition) recent inclusion of Binge Eating Disorder, RDNs face difficult questions about how to address the issue of food addiction.

Below I’ll review the most recent scientific literature, completed by H. Ziauddeen and PC Fletcher in an article entitled, “Is Food Addictive? Is food addiction a valid and useful concept?” It’s an excellent article if you’re interested in a more thorough examination from both a neuroscience and clinical perspective.

Food Addiction Theory

Proponents of the term food addiction often cite four similarities between food and other addictive substances.

1. Food shares common drug pathways in the brain.
2. Food can activate reward neurons.
3. When consumed, dopamine receptors are altered.
4. Anticipation of eating activates brain regions seen in drug abuse.

Limitations of the Food Addiction Theory

While the concept of food addiction is extremely compelling, there are a number of reasons to exercise caution in its application. First, there is no actual definition of an addictive food. Researchers have yet to categorize which elements are addictive, identify if the term refers to one or many addictive substances, or characterize which features interact with individual vulnerabilities. “Although arguments have been made that certain aspects of eating in obesity are ‘addictive,’ we would caution against less stringent applications of an addiction model as these risk losing the explanatory power and the neurobiological grounding of the model.”

Second, there is very little research that supports the food addiction model. Much of the research has been done on animals. The outcomes of these studies contain elements that seem promising, while the results of the limited human studies are largely conflicting. The authors state that “the potential role of FA in the obesity epidemic … has acquired much currency with relatively little supporting it.” They go on to say that “… food addiction is unlikely to be a causal pathway in the majority of people with obesity.”

Third, the food addiction theory fails to consider other viable explanations for neurobiological phenomena. At RDN Evelyn Tribole’s April 2013 “Intuitive Eating Training” event in Salt Lake City, she suggested four limitations to the food addiction model to consider:

• Pavlovian conditioning
• Food is meant to be rewarding
• Restrained eating increases the hedonic value of the food
• Hunger increases neural activation

The final consideration I’d like to suggest is more subjective. RDNs need to consider and openly discuss with their clients whether the concept of food addiction is empowering for them. This is where the blend of art and science is critical. In my clinical experience, many of my clients express feelings of hopelessness and powerlessness when they think of themselves as food addicts. This often results in a cycle of restrictive eating followed by binge eating.

Clinical Suggestions for the RDN
As nutrition experts, RDNs are perfectly positioned to stay current on the latest food addiction research and interpret those findings for their clients. Given the fact that the research on food addiction is in its infancy, RDNs should stay tuned for new information. And in the interim, consider alternative approaches to help clients reduce compulsive and binge eating. Intuitive Eating, a program developed by two RDNs, is one such method that has garnered significant research in the past few years. For a listing of all the research, click here.