Clinical Evaluation of Blood Glucose Regulation and Safety of Cordyceps cicadae Mycelium

Cordyceps cicadae (C. cicadae) is one of the most valued traditional Chinese medicines and have been used for about 1600 years in China. It is edible and is used traditionally for vision improvement, renal protection, cancer treatment and regulation of blood cholesterol and blood glucose. The aim of this study was to evaluate the safety and to determine the effects of Cordyceps cicadae (C. cicadae) mycelium on hyperglycemic patients or type 2 diabetic patients by a single-blind, randomized, parallel-group, and placebo-controlled trial. In the treatment group, 22 subjects ingested a supplement containing freeze-dried C. cicadae mycelium powder (1050 mg/day) in hard capsule form, every day for 3 months. In the placebo group, 18 subjects ingested placebo capsules. Before supplementation, subjects completed a questionnaire to assess for personal data (age, medical history, medication record, physical activity). Subjects underwent blood pressure reading, anthropometric measurements, biochemical investigations, oral glucose tolerance test (OGTT) and urinalysis at baseline, the end of treatment period, and the end of follow-up period. Based on the results, freeze-dried C. cicadae mycelium powder could maintain blood glucose level in hyperglycemic patient or type 2 diabetic patients. Besides, no toxicity observed in kidney and liver. Results from the study do not raise concern with respect to possible use as a functional food ingredient. This study provides support for the use of C. cicadae fermentation product as a safe agent in functional food.