Efficacy and Safety of Tremella fuciformis in Individuals with Subjective Cognitive Impairment: A Randomized Controlled Trial

Authors:
Soonhyun Ban, Suji L. Lee, Hyeonseok S. Jeong, Soo Mee Lim, Shinwon Park, Young Sun Hong, Jieun E. Kim

Journal:
Journal of Medicinal Food

Study Design:
Randomized, double-blind, placebo-controlled clinical trial

Participants:
75 community-dwelling individuals aged 40 to 65 years with subjective cognitive impairment (SCI). Participants were divided into three groups: high-dose Tremella fuciformis (1200 mg/day, n = 30), low-dose Tremella fuciformis (600 mg/day, n = 30), and placebo (n = 15).

Intervention:

• High-dose group: 1200 mg/day of Tremella fuciformis, administered in 6 capsules daily for 8 weeks.
• Low-dose group: 600 mg/day of Tremella fuciformis, administered in 6 capsules daily for 8 weeks.
• Placebo group: 6 placebo capsules daily for 8 weeks.

Outcome Measures:

1. Primary Outcome Measure:
   • Changes in Subjective Memory Complaints Questionnaire (SMCQ) scores.
2. Secondary Outcome Measures:
   • Cognitive performance, measured through standardized short-term memory and executive function tests.
   • Structural brain changes, assessed via voxel-based morphometry.
3. Safety Measures:
   • Adverse event frequency, physical exams, and laboratory tests.

Summary:
This clinical trial evaluated the efficacy and safety of Tremella fuciformis supplementation in individuals with SCI. The study found significant improvements in memory complaints (SMCQ scores) in both high-dose (P = .002) and low-dose (P = .007) groups compared to the placebo. High-dose supplementation significantly enhanced executive function (P = .02), while both doses improved short-term memory (P = .001). Imaging results revealed increased gray matter volumes in brain regions, including the dorsolateral prefrontal cortex, which correlated with executive function improvements (P = .02).

No serious adverse events were reported, and the supplementation was well tolerated. This study suggests that Tremella fuciformis is a safe and promising option for improving memory complaints and cognitive performance in middle-aged adults with SCI. Further studies are recommended to optimize dosing and explore broader cognitive benefits