Author: Liz

Using Animal Research to Justify Eating Disorder Treatment Practices: Are We Going Too Far? (On Eating Junk Food in Treatment – Part II)

Liz 10 Comments

As a follow up to Charlene’s  post on eating hyper-palatable foods during eating disorder treatment , I asked Liz–SEDs’ resident expert on animal behaviour, particularly in relation to binge eating and drug addiction–to look at some of the studies that Julie O’Toole mentioned as evidence for Kartini Clinic’s guidelines of avoiding hyper-palatable foods for the first year of eating disorder recovery. If you missed Dr. O’Toole’s post, please do take a look. Here’s the main conversation that led to this post: 

In the comments, I asked Dr. O’Toole, 

I agree that eating cheetos and sugar-y drinks is ubiquitous but not exactly healthy, and I too question many versions of “normal eating” that people promote (and *everyone* has an opinion), but I wonder — if there’s any evidence for not allowing hyper-palatable foods to patients for a year? And what does the Kartini Clinic consider to be hyper-palatable? Why

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Models of Anorexia Nervosa: A Few Insights from Our Animal Cousins

Liz 6 Comments

In 1967, Routtenberg and Kuznesof reported a very peculiar phenomenon in rats:

They discovered that when rats were on a restricted feeding schedule (1 hour per day in their experiment) and had free access to a running wheel, their food intake was significantly lower than in control rats, which were on the same feeding schedule but without access to a running wheel. This discrepancy between increased running activity and decreased food intake caused substantial body weight loss, and if rats were not removed from the experimental setup timely, they would eventually die of starvation. This model, later named the activity-based anorexia (ABA) model, is one of the most widely used animal models for the study of anorexia nervosa (AN). (Source)

Of course, rats are not humans. Nonetheless, animal models of anorexia nervosa can inform us of some of the underlying neuropsychological and physiological influences and consequences of … Continue reading →

Bingeing Because Food is Yummy: A Stepping Stone Toward Recovery from Anorexia and Bulimia?

Liz 8 Comments

This may sound counterintuitive at first, but I’m thankful for two aspects of my eating disorder, which I believe helped me make the choice to aim towards recovery: the development of binge eating after chronic food restriction and the physical inability to purge through self-induced vomiting. Like many individuals diagnosed with anorexia nervosa that go on to develop binge eating, I tended to choose high-fat foods and sweets as my “go-to” food items. I had always enjoyed such foods and was a notorious junk food aficionado as a young girl (way before any eating disorder symptoms developed). Once the bingeing behavior started, I couldn’t stop.

Sitting with the discomfort after a binge made me seriously consider whether this was something I could maintain for any lengthy period of time, and that’s when I started getting help. In a sense, I believe my affection for sweet foods, and propensity to binge … Continue reading →

How Much Can We Learn About Eating Disorders From Animal Research?

Liz 4 Comments

I have been studying the neurobehavioral aspects of food and drug reinforcement for the past 5 years (read more about it on my profile page). This involves using rats to mimic basic human behaviors surrounding food and drug intake. I then manipulate various neurotransmitter systems by using drugs and observe the effects this manipulation has on the behaviors I am interested in.

What’s important to this type of research is that we constantly challenge and evaluate the validity of using these animal models to study complex human diseases and disorders. Validity can be divided into several categories, but I’m going to focus on two in particular and relate them to an animal model of binge food intake.  These two types of validity are predictive validity and construct validity:

  1. Predictive validity, when comparing animal research to human research, refers to the ability for some measure of animal behavior
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Bingeing and Purging: Keeping the “Positives” and Eliminating The Negatives?

Liz 11 Comments

I have been fascinated and perplexed by reports of the seemingly invigorating and anxiety reducing effects of bingeing and purging (purging by self-induced vomiting). Personally, I cringe at the idea of self-induced vomiting and have always wanted to avoid vomiting at all costs, including during food poisoning. The insight from recent blog entries and the subsequent comments has made an impact on me. I see that the motivation to engage in bingeing/purging behavior can be intense and can provide an effective way increase positive affect and reduce stress. The ameliorating effects of bingeing/purging remind me of drug addiction, with bingeing/purging behavior as the “drug.”  This made me wonder, what happens in the brain to impart such “addiction-like” reinforcement?

I know there are reports of opiate and endorphin release following purging, but to me, this seemed like an effect meant to counter the intense aversion (and discomfort?) of the act … Continue reading →

Binge Eating: When Should We Call It An “Addiction”?

Liz 10 Comments

The recent New York City soda ban controversy has contributed to increased discussion about the “addictive” properties of sugar and its contribution to the obesity epidemic. While I do not deny that there is an overabundance of high-sugar/high-fat foods in the societal milieu, and that the rewarding properties of these foods encourages their overconsumption; I think it is a mischaracterization to refer to the typical overeating associated with the “obesity epidemic” as reflective of a widespread “sugar addiction” that millions have fallen prey to.

Stice, Figlewicz, Gosnell, Levine, and Pratt (2012) have recently released a review in Neuroscience and Biobehavioral Reviews entitled “The contribution of brain reward circuits to the obesity epidemic.” In the paper, the authors elegantly describe the overlap between food and drug rewards while also highlighting major differences.

BRIEF INTRO TO DOPAMINE SIGNALLING

Before discussing the parallels between food and drug rewards, we should first introduce some … Continue reading →