• Posted August 1, 2023

Psilocybin May Help Some Who Battle Anorexia

One dose of the hallucinogenic ingredient in "magic mushrooms" may help some people with anorexia move past their preoccupation with body image, an early study suggests.

The study, of just 10 women with anorexia, tested the effects of a single dose of psilocybin plus psychological counseling sessions.

Researchers found that the treatment appeared safe, with patients rating the experience as a positive one.

And within three months, four of 10 women had a significant improvement in their eating disorder "pathology." That meant certain eating-disorder behaviors -- including preoccupation with weight and body shape -- improved to the degree that they were close to what's typical of people without an eating disorder.

There are plenty of caveats in the findings, however, experts said.

The phase 1 trial was small and designed primarily to make sure the treatment was feasible and safe. So, no conclusions can be drawn about the effectiveness.

Still, the early findings indicate that psilocybin is worth further study, said Dr. Evelyn Attia, director of the Center for Eating Disorders at Columbia University and Weill Cornell Medicine, in New York City.

"I'd very much like for this to be studied further," she said.

Attia, who was not involved in the study, is also with the National Eating Disorders Association (NEDA).

At any given time, about 0.4% of young women and 0.1% of young men are suffering from anorexia, according to NEDA. People with anorexia obsess over weight and food, and typically have a distorted body image. They severely restrict what and how much they will eat, often to the point of becoming dangerously underweight.

"Anorexia is really, really difficult to treat," said lead researcher Stephanie Knatz Peck, an associate clinical professor at the University of California, San Diego's Eating Disorder Treatment and Research Center.

People with anorexia, she explained, often feel "ambivalent" about treatment because their entrenched behaviors are the very things that make them feel better. And while standard psychological therapies can help many people develop healthier attitudes toward food and their bodies, they are not always effective.

"Our treatments often fail patients," Peck said, noting that about 20% of people with anorexia develop a chronic condition.

So there's a great need for innovative options, she explained.

Enter psilocybin. As the active ingredient in so-called magic mushrooms, the substance has long been used recreationally as a hallucinogen -- meaning it alters people's perceptions of their surroundings, and their own thoughts and feelings. That could end badly -- if users think they can fly, for example.

But recent years have seen a growing interest in psilocybin as therapy. In the United States, researchers at institutions like New York University, the University of California and Johns Hopkins University are studying psilocybin-assisted therapy for psychiatric conditions like major depression and addiction.

For example, a 2021 study found that psilocybin was as effective as a standard antidepressant at easing patients' depression symptoms over six weeks. Both drugs were used along with psychological counseling -- an essential component, experts noted.

For the latest study, published recently in the journal Nature Medicine, Peck's team recruited 10 women with anorexia, some of whom were in partial remission. They received one dose of a pharmaceutical-grade synthetic psilocybin formulation, under medical supervision, along with psychological counseling sessions before and after the treatment day.

Overall, the study found, the treatment was largely safe, though two patients had low blood sugar episodes. Three months later, the participants typically gave high ratings to the experience -- with most saying they felt more optimistic and were placing less importance on physical appearance.

On average, participants' weight and body shape concerns decreased, and for four the improvement was "clinically significant," according to Peck's team.

But the study lacked a control group that did not receive psilocybin, Attia cautioned. So, it's not possible to know if the changes were due to psilocybin, or to taking part in a study of a novel therapy.

"You can imagine that people would come into the trial with a great deal of expectation," Attia said.

Nor did participants' body weight increase, on average.

What's needed is a larger trial that tests psilocybin against a comparator -- and one is currently underway, Peck said.

The research is being funded by Compass Pathways, which is developing the psilocybin product. Peck is a consultant for the company.

How does psilocybin work? The drug's immediate impact stems from stimulation of brain receptors for the chemical serotonin, which helps regulate mood. What's unclear, researchers say, is why one dose of psilocybin can have longer-lasting effects.

Anorexia involves underlying biological vulnerabilities, Attia pointed out. However, there are no medications specifically designed for the disease, to make the treatment process easier for patients, she said.

Whether psilocybin targets any biological mechanisms involved in anorexia is unknown. But more research is needed in that area, Attia said.

More information

The National Eating Disorders Association has more on anorexia.

SOURCES: Stephanie Knatz Peck, PhD, associate clinical professor, Eating Disorder Treatment and Research Center, University of California, San Diego; Evelyn Attia, MD, director, Center for Eating Disorders, Columbia University Medical Center and Weill Cornell Medicine, New York City, co-chair, research advisory council, National Eating Disorders Association, New York City; Nature Medicine, July 24, 2023, online