The active chemical in “magic mushrooms” may help treat anorexia, a new study has found.

Following psilocybin treatment, 4 of 10 study participants showed clinically significant reductions in their anorexia-driven eating habits, researchers report.

“Our findings suggest that psilocybin may be helpful in supporting meaningful psychological change in a subset of people with anorexia nervosa,” said lead researcher Stephanie Knatz Peck, a clinical associate professor with the University of California, San Diego's Eating Disorder Center.

For the study, 10 adult women diagnosed with anorexia received a single 25-milligram dose of synthetic psilocybin, combined with specialized psychological support.

People with anorexia obsess about their weight and their food intake. They might severely limit the amount of food they eat, or they might binge on food and then throw up or take large amounts of laxatives to purge their bodies.

Nine out of the 10 women treated with psilocybin ranked the session among their top five most meaningful life experiences, researchers report.

The results first appeared in a 2023 issue of Nature Medicine, and were more fully described in a report published Nov. 7 in the journal Psychedelics.

 “What's particularly interesting is that 60% of participants reported a reduction in the importance of physical appearance, while 70% noted quality-of-life improvements and shifts in personal identity,” Knatz Peck said in a journal news release.

However, the changes in their psychological outlook didn’t automatically translate to weight restoration, researchers found.

The women themselves described the effect that psilocybin had on them:

• “You are able to act in a way that maybe had felt unachievable before if you set the right intention,” one participant said.

• “Things might not look that different from the outside, but they feel completely different from the inside,” another noted.

However, the researchers warned that psychedelic therapy likely will work best as part of a comprehensive treatment approach, given that anorexia is a complex disorder.

Larger, well-controlled studies that include brain imaging and genetic analysis can help researchers better understand the therapeutic value of psilocybin, the researchers said.