Reishi mushroom extract was associated with greater improvement in chronic insomnia severity than melatonin in an 8-week randomized controlled trial presented during a late-breaking study session at SLEEP 2026.
In the parallel-group trial of 218 adults with chronic insomnia, participants were randomly assigned 1:1 to receive either melatonin 5 mg nightly or reishi mushroom extract 980 mg nightly standardized to 6% triterpenes. The primary outcome was change in Insomnia Severity Index (ISI) score from baseline to week 8.
Key Facts
- In an 8-week randomized trial, reishi mushroom extract reduced ISI scores more than melatonin in adults with chronic insomnia.
- Mean ISI score change was –8.7 with reishi vs –5.6 with melatonin, for a between-group difference of –3.1 points.
- The treatment effect remained significant after adjustment for age, sex, and baseline ISI score.
- Study completion was high (95.9%), and no serious adverse events were reported.
- Findings support further study but should be interpreted cautiously given the short duration and conference-abstract format.
Both groups experienced significant improvement in insomnia severity, but the reduction was greater among participants assigned to reishi mushroom extract. Mean ISI score change was –8.7 ± 4.1 in the reishi group compared with –5.6 ± 3.8 in the melatonin group, for a between-group difference of –3.1 points (95% CI, –4.2 to –2.0; P<.001).
The treatment effect remained statistically significant after multivariable adjustment for age, sex, and baseline ISI score, according to investigator Ching Xie, MD, of Brooklyn Unity Medical Care P.C.
Melatonin is commonly used by patients with chronic insomnia, although clinical response varies. Reishi mushroom, or Ganoderma lucidum, contains bioactive triterpenes that may influence sleep regulation. According to the abstract, these compounds have been shown to affect insomnia primarily through modulation of GABAergic neurotransmission and regulation of neurotransmitter homeostasis, though comparative clinical data have been limited.
Participants were enrolled between December 12, 2025, and February 7, 2026. Data verification and statistical analyses were completed on February 21, 2026. Analyses followed an intention-to-treat approach, and between-group differences were assessed using independent t tests and multivariable linear regression.
Of the 218 randomized participants, 209 completed the study, for a completion rate of 95.9%. No serious adverse events were observed during the trial.
The findings suggest reishi mushroom extract may warrant further study as a potential alternative to melatonin for adults with chronic insomnia. However, the results should be interpreted in the context of a single short-term trial presented as a conference abstract. Additional research is needed to confirm efficacy, assess longer-term safety, evaluate durability of benefit, and determine which patient groups may be most likely to respond.
“These findings suggest that reishi mushroom extract may represent a safe and effective alternative treatment for chronic insomnia and support further investigation,” Xie concluded.
Reference: Xie C. Can’t sleep? Take some shrooms: comparing reishi mushroom versus melatonin for chronic insomnia. Presented at: SLEEP 2026; June 2026.
