The quality of commercially available nutraceutical supplements and food sources

Abstract

Nutraceuticals are components of dietary origin, with claimed beneficial therapeutic activities. The quality of nutraceuticals is paramount for efficacy and safety, and it includes quality of raw materials, different available chemical forms, complex products, lack of substitution of inappropriate materials, and the absence of contaminants. The aim of this review is to investigate the extent of substandard formulated and raw material nutraceuticals, and to highlight any consequent health concern. Reports of the quality of raw materials have revealed wide variations, often as a result of lack of clear regulatory definitions with respect to size of polymeric entities and also presence of glycosidic and salt forms. Published evaluations of over 70 formulations of 25 different nutraceuticals revealed variable quality; no nutraceutical showed consistent high quality, but a number revealed consistent low quality, thereby making the case for closer regulation of manufacturers. Whole food sources have also been shown to be widely variable in constituent levels. The effect of different formulations requires consideration, as the different types have been shown to have marked effects on bioavailability. The poor quality of commercially available nutraceuticals has been highlighted. In addition, incidences of side effects and drug interactions are increasing, as consumption of nutraceuticals rises. Pharmacists and health practitioners need to be aware of the scientific literature to advise accordingly.