An analysis of nine proprietary Chinese red yeast rice dietary supplements: Implications of variability in chemical profile and contents

Objectives: Some strains of Chinese red yeast rice, when prepared by solid fermentation, produce compounds called monacolins that inhibit cholesterol production. When used as a dietary supplement to achieve and maintain healt hy cholesterol levels, Chinese red yeast rice has significant potential to reduce health care costs and contribute to public health by reducing heart disease risk in individuals with moderate elevations of circulating cholest erol levels. Whereas one proprietary strain of Chinese red yeast rice has b een demonstrated to lower cholesterol levels significantly in clinical tria ls, other strains being sold as Chinese red yeast rice dietary supplements have not undergone similar evaluation. In order to determine whether the re sults of a clinical trial conducted with one strain of Chinese red yeast ri ce could be generalized to other preparations of Chinese red yeast rice, ni ne different commercially available dietary supplements were purchased test ed for chemical constituents. Design: Monacolins were measured by high performance liquid chromatography (HPLC) that separates the various monacolins in Chinese red yeast rice. Cit rinin concentration, a toxic fermentation byproduct, was measured by radioi mmunoassay. Results: Total monacolin content varied from 0% to 0.58% w/w and only 1 of 9 preparations had the full complement of 10 monacolin compounds. Citrinin was found at measurable concentrations in 7 of the 9 preparations. Conclusions: The findings from clinical trials demonstrating significant an d clinically relevant cholesterol reduction using a defined Chinese red yea st rice preparation containing 10 different monacolins cannot be generalize d to preparations that do not contain the same levels and profile of monaco lins. Standardized manufacturing practices should be established for Chines e red yeast rice sold as a dietary supplement in order ensure equivalence o f content of active ingredients in preparations being sold to the public an d to limit the production of unwanted byproducts of fermentation such as ci trinin. bn common with Other botanical dietary supplements, the full potent ial of this product will not be realized until standards for production and labeling of Chinese red yeast rice are further developed.