Safety and Tolerability of Ganoderma lucidum in Healthy Subjects: A Double-Blind Randomized Placebo-Controlled Trial

Authors: Sheila M. Wicks, Robin Tong, Chong-Zhi Wang, Michael O’Connor, Theodore Karrison, Shang Li, Jonathan Moss, and Chun-Su Yuan

Journal: The American Journal of Chinese Medicine

Study Design:

• Intervention: 2 grams of Ganoderma lucidum extract or placebo twice daily
• Participants: 16 healthy volunteers
• Duration: 10 days
• Outcome Measures:
  • Subjective questionnaires
  • Electrocardiograms
  • Complete blood counts
  • Blood chemistry analysis
  • Urinalysis
  • Blood tests reflecting immunity (CD4, CD8, CD19, CD56)

Summary: This study investigated the safety and tolerability of Ganoderma lucidum extract in healthy volunteers. The extract was well-tolerated, and no adverse effects were observed compared to the placebo group. There were no significant changes in CD4, CD8, or CD19 cell counts after taking the extract. However, there was an increase in CD56 cell count (a marker for natural killer cells) during the study, which returned to baseline 10 days after stopping the extract. This increase was not statistically significant, possibly due to the small sample size and high variability. The study suggests that Ganoderma lucidum extract is safe for short-term use, but further research is needed to evaluate its long-term safety and effects on the immune system.