A Clinicians Guide to Recommending Common Cholesterol-Lowering Dietary Supplements

Abstract

The US dietary supplement (DS) market has expanded exponentially since 1994, with an estimated 50,000–80,000 individual products currently available. Many DS claim cholesterol or cardiovascular benefits. Overall, well-designed randomized controlled trials (RCTs) with DS are lacking, while studies with favorable results are commonly performed outside of the USA, resulting in inconsistent findings. The expansion of the DS market has limited the ability of the Food and Drug Administration to regulate and prevent substandard products. Eicosapentaenoic acid and docosahexaenoic acid are components of DS fish oil. Recent RCTs utilizing prescription fish oil have provided mixed findings and small but significant safety concerns. Hence, the role of DS fish oil is limited and no longer recommended by major cardiovascular guidelines. Concerns have also been observed from RCTs utilizing prescription niacin, resulting in a negligible role for DS niacin in lipid management. Red yeast rice has demonstrated significant low-density lipoprotein cholesterol (LDL-C) reductions in studies performed worldwide, including the USA. However, quality concerns and inconsistent study results have been reported on multiple occasions. Other common DS have produced modest reductions in LDL-C and may provide other cardiometabolic benefits, including garlic, phytosterols, psyllium, and berberine. Yet inconsistent study results and quality concerns continue to be reported for most. Nonetheless, there is a need for alternative therapies that can safely and effectively reduce cardiovascular risk. However, until DS routinely match label claims and are free of contaminants, the agents have a limited role in clinical practice.