Psilocybin and Eating Disorders: Emerging Evidence for Anorexia and Bulimia
Eating disorders are among the most treatment-resistant conditions in psychiatry. Anorexia nervosa has the highest mortality rate of any mental health disorder — higher than depression, higher than schizophrenia. Standard treatments (CBT, nutritional rehabilitation, SSRIs) produce full recovery in only about 30–40% of patients, and relapse rates are high.
Against this backdrop, the early evidence on psilocybin for eating disorders is genuinely exciting — not as a cure, but as a potential catalyst for the psychological breakthroughs that conventional therapy alone cannot reliably produce.
Why Eating Disorders Are So Hard to Treat
Eating disorders are not simply about food. They are fundamentally disorders of self-perception, control, and identity. The cognitive rigidity that characterises anorexia — the inability to update beliefs about one's body despite overwhelming evidence — is one of the most treatment-resistant features in all of psychiatry.
This rigidity is reflected in the brain: neuroimaging studies show that people with anorexia have abnormally high activity in the DMN (the self-referential thought network) and reduced serotonin 2A receptor density in the prefrontal cortex. Both of these are directly targeted by psilocybin.
The UCSF Psilocybin for Anorexia Trial
The most significant study to date is a 2023 open-label trial at the University of California San Francisco, led by Dr. Natalie Gukasyan. Ten women with anorexia nervosa received two psilocybin sessions alongside psychotherapy. At the one-month follow-up, participants showed significant reductions in eating disorder psychopathology scores, reduced body image disturbance, and — crucially — weight gain in several participants who had been medically stable but psychologically stuck.
Qualitative reports were striking. Participants described psilocybin as allowing them to "step outside" their eating disorder identity for the first time, to observe their relationship with food and their body from a new perspective, and to access a sense of self-worth that the eating disorder had obscured.
Psilocybin and Bulimia
Bulimia nervosa and binge eating disorder share neurobiological features with addiction — specifically, dysregulation of the dopamine reward circuit and impaired impulse control. Psilocybin's effects on the serotonin system can modulate dopamine activity, and its promotion of psychological flexibility may help break the binge-purge cycle.
A 2022 case series from Johns Hopkins described three patients with bulimia who underwent psilocybin-assisted therapy. All three showed significant reductions in binge-purge frequency at the three-month follow-up, with two achieving full remission. While this is preliminary, it aligns with psilocybin's documented effects on compulsive behaviours more broadly.
The Role of Mystical Experience
Across all eating disorder studies, the intensity of the mystical-type experience during psilocybin sessions is the strongest predictor of outcome. Participants who report a sense of unity, transcendence of time and space, and deep emotional release show the greatest improvements. This suggests that psilocybin's mechanism in eating disorders is not purely pharmacological — it is experiential, working through the profound psychological shifts that the experience itself produces.
Frequently Asked Questions
Can psilocybin help anorexia nervosa?
Early clinical evidence is promising. A 2023 UCSF trial showed significant reductions in eating disorder psychopathology and improved body image after two psilocybin sessions. Larger trials are underway.
Is psilocybin safe for people with eating disorders?
People with eating disorders who are medically unstable (severely underweight, electrolyte imbalances) should not undergo psilocybin therapy until stabilised. For those who are medically stable, the safety profile appears acceptable, though close monitoring is essential.
Can microdosing help with eating disorder recovery?
There is limited formal evidence, but anecdotal reports suggest microdosing may help reduce the obsessive thought patterns and anxiety that sustain eating disorders. It is not a replacement for structured treatment.