On the Efficacy of Self-Induced Vomiting (Purging)

A single in-lab assessment of caloric consumption, loss, and retention during binge-purge episodes in individuals with bulimia nervosa (BN) is frequently cited as evidence that purging via self-induced vomiting is an ineffective strategy for calorie disposal and weight control (Kaye, Weltzin, Hsu, McConaha, & Bolton, 1993). These findings have been widely interpreted to mean that, on average, purging  rids the body of only about half of the calories consumed, regardless of total quantity.

However, a closer examination of the study does NOT support the notion that purging is an ineffective compensatory behavior. Indeed, the findings of Kaye et al. (1993) would appear to have been both misunderstood and overgeneralized in the subsequent decades. This has important implications for therapeutic alliance in clinical practice as well as for understanding the nature of symptoms, metabolic processes, and physiological alterations in EDs.


The study included 17 individuals, all of … Continue reading →

Your Body’s Response to Chewing and Spitting: The Role of Insulin

In my previous post, I looked at two hormones released during the cephalic phase (gastric secretion that occurs before food is eaten), ghrelin and obestatin, and how they may contribute to runaway eating behavior. Today I’m going to be looking at insulin release during chew and spit (CHSP), a fairly common symptom in eating disorders where the food is tasted, chewed and spit out. Insulin is a small peptide hormone that acts as a key regulator of metabolism; deregulation of insulin signalling plays a role in illnesses such as diabetes and metabolic syndrome. Some people have theorized that CHSP behavior may influence insulin regulation. In fact, there are a number of individuals stating on internet forums that chronic CHSP could lead to insulin resistance, potentially promoting diabetes. As interesting as these theories are, recent data have shown that they are probably not true.


Bingeing and Purging Marathons: Repeated Binge/Purge Cycles in Bulimia Nervosa

I used to call them bingeing and purging marathons. If I binged and purged in the morning, chances were, I’d binge and purge throughout the day. The next time I’d eat, I was likely to end up–whether I wanted to or not–bingeing and purging. Not all individuals with bulimia nervosa binge and purge every day (or purge everything they eat, for that matter), but many do, and some binge and purge multiple times a day. In recovery, many people start by trying not to binge and purge before a certain time of the day–because once they binge and purge, it triggers a continuous cycle of bingeing and purging until they become to exhausted or otherwise end up going to bed.

I always wondered why that was, why was it so hard to keep a single episode of bingeing and purging from initiating a repeated cycle of bingeing and purging?

On … Continue reading →