Effects of policosanol supplements on serum lipid concentrations : a systematic review
Walsh, Chantal Patrica
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Motivation The leading cause of death for several years has been diseases of the heart and blood vessels. At present, concerns regarding cardiovascular disease motivate several health practitioners to search for a product that has the ability to assist with improvement of lipid profiles with few or no adverse effects and is affordable and safe for use in all population groups. Over the past ten years nutritional supplements and nutraceuticals have become extremely popular amongst the general population. One such product that has been in the limelight is policosanol, a mixture of long-chain aliphatic primary alcohols. Objectives The objective of this study was to determine the efficacy of policosanol, a relatively new supplement primarily derived from sugar cane, in the reduction of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) and increase in high-density lipoprotein cholesterol (HDL-C). Methods This study is presented in a systematic review format. Literature from January 1990 to May 2008 regarding the source, metabolism and mechanism of action of policosanol was reviewed and those randomised controlled trials focusing on the effect of policosanol on the lipid profile of humans were extracted onto predefined tables and the absolute data was then evaluated and results, recommendations and conclusions were provided. Results A total of 39 trials were identified. The majority of these indicated a beneficial link between the daily intake of policosanol and serum lipid level reduction. However, all of these studies were performed in Havana, Cuba prior to 2004. The initial studies (85%) indicated a mean percentage change of-17.57%, -29.5% and +19% in TC, LDL-C and HDL-C respectively within the experimental group. The dosage administered ranged from 1 mg/day to 80 mg/day, with the bulk between 5 and 20 mg/day, while the duration ranged from 30 days to 24 months. The more recent 15% of the trials were performed independently in various countries. These studies found no favourable effects with the use of policosanol. Reasons suggested to cause such diverse results include differences in composition of policosanol, concentration of octacosanol, ethnic and environmental influences, however, these have been discarded as inconsistent factors. Conclusion Concern is raised regarding the results of the trials performed in Cuba, as these remarkable results have yet to be replicated in other areas of the world by independent research groups using the same or alternative extract of policosanol that was used in Cuba. Therefore, in order to ensure that the benefits of policosanol are in fact true, further studies using the original policosanol are required (although the results of some studies already indicated no difference between the composition and effect of original and alternative sources of policosanol)- Future research should include long-term studies using controlled methods incorporating volunteers from countries around the world, focusing on the mechanism of action, rate and amount of absorption and different compositions of policosanol sources. Ideally, an interlaboratory study should be performed by experienced investigators in different international centres, coordinated from a central laboratory, using the original as well as an alternative policosanol in a double blind manner.
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