The Benefits of Starving – Part II (Restricting Reduces Anxiety in Anorexia Nervosa)

What is different about anorexia nervosa sufferers that, in contrast to most dieters, enables them to maintain a persistent calorie deficit? Although no one can truthfully claim they know the full answer to that question, we do know that part of the answer most likely lies with serotonin (5-HT), a molecule that neurons use to communicate with each other.

I’ve written about serotonin in the context of anorexia nervosa before, so I’ll just do a brief summary of the important points here:

  • Serotonin has a lot of functions in the body; it plays a role in regulating appetite (satiety), sleep, mood, behaviour, learning and memory, and a variety of other things
  • Serotonin has been implicated in obsessionality, harm avoidance, and behavioural inhibition
  • Alterations in serotonin function have been linked to many disorders, including depression, OCD, anxiety, and eating disorders
  • Serotonin is made from tryptophan, an essential amino acid
Continue reading →

Endophenotypes and Biomarkers in Eating Disorders: Genetic Underpinnings, Personality Traits, Vulnerabilities – Part 1

There have been some interesting discussions on the F.E.A.S.T. Facebook group over the past month regarding the role of genetics, personality traits, environmental factors and their role (or lack thereof) in the development of eating disorders and their prognosis. A parent group may seem like an unlikely forum for several hundred-odd comment threads on etiology; however, what we (caregivers, patients or clinicians) believe to underlie these disorders naturally informs our attitudes, decisions and choices with regards to treatment and our relationship to the disorders themselves:

Is this something they will have to manage their entire life?
Does anyone ever fully recover?
I had bulimia as a young adult and now my son has an eating disorder, too – did I pass on “bad genes”, bad habits, or is it a coincidence?
Is her rigidity and anxiety merely a side affect of starvation, or should we treat those as
Continue reading →

Serotonin Function in Bulimia Nervosa – Brain Circuits & Behaviour

Serotonin (5-hydroxytryptamine, 5-HT) is a neurotransmitter that is involved in just about everything. It helps ensure proper cell growth, maturation and migration during development. Serotonin is also important in regulating emotions, cognitive functions, appetite, pain, circadian rhythms, and our endocrine system in adulthood. It is hardly a surprise then, that the serotonergic system seems to be important in bulimia nervosa (BN).

I’ve written previously about serotonin in restricting-type anorexia nervosa, so for this post I’m going to be shifting focus and talk about bulimia and binge-purge type anorexia nervosa (AN-BP).

The information in this post isn’t coming from a review paper. Instead, I’m going to be summarizing and explaining information from a chapter in a book titled Behavioural Neurobiology of Eating Disorders. In the chapter on serotonin and bulimia, Howard Steiger and colleagues propose a model for serotonin action in bulimia nervosa which takes into account “diverse hereditary Continue reading →