Nagano M., Shimizu K., Kondo R., Hayashi C., Sato D., Kitagawa K., Ohnuki K. Reduction of depression and anxiety by 4 weeks Hericium erinaceus intake. Biomed Res. 2010;31(4):231–237.
Rationale
The fruiting body of Hericium erinaceus contains hericenones and erinacines — low-molecular-weight compounds that stimulate nerve growth factor (NGF) synthesis — giving grounds to expect effects on central nervous system function and autonomic regulation. This work assessed the clinical effects of 4 weeks of H. erinaceus on menopausal symptoms, depression, sleep quality and nonspecific complaints — states in whose pathogenesis autonomic and neurotrophic imbalance plays a meaningful role.
Methods
A randomized double-blind placebo-controlled trial: 30 women, predominantly in the menopausal period, received cookies with H. erinaceus fruiting-body powder (4 cookies × 0.5 g = 2.0 g/day) or identical placebo cookies for 4 weeks. Scales: Kupperman Menopausal Index (KMI), CES-D depression scale, Pittsburgh Sleep Quality Index (PSQI) and Indefinite Complaints Index (ICI).
Results
After the course, the active group's CES-D and total ICI scores fell significantly from baseline; on the ICI subscales "insentive" and "palpitatio" the active group significantly outperformed placebo, while "concentration," "irritating" and "anxious" showed only trends. No adverse events were recorded.
Conclusions
Four weeks of H. erinaceus intake reduced depression scores and nonspecific complaints in this group — a modest but real signal in a population prone to mood and autonomic symptoms.
Worth noting
The honest framing matters: significant effects appeared on the total ICI and two subscales, not on the headline menopausal or sleep measures — KMI and PSQI did not clearly move. The delivery form (cookies with 2 g of powder) is culinary rather than pharmacological — a strength for real-world relevance and a weakness for standardization. n=30 in a symptom-scale study detects only fairly large effects; the trend-level subscales should not be read as failed proof or proof.