ANALYSIS OF ω-3 FATTY ACID CONTENT OF POLISH FISH OIL DRUG AND DIETARY SUPPLEMENTS

Abstract

Study results indicate that a diet rich in polyunsaturated fatty acids ω-3 (PUFA n-3) exerts favorable effect on human health, accounting for reduced cardiovascular morbidity and mortality. PUFA n-3 contained in marine fish oils, particularly eicosapentaenoic (EPA, 20:5 n-3) and docosahexaenoic (DHA, 22:6 n-3) acids, are attributed antithrombotic, anti-inflammatory, anti-atherosclerotic and anti-arrhythmic effects. They have also beneficial effects on cognitive functions and immunological mechanisms of an organism. Considering the fact that marine fish are not abundant in Western diet, the pharmaceutical industry reacts with a broad selection of PUFA n-3 containing dietary supplements and drugs. Increased consumers' interest with those products has been observed recently. Therefore, their quality, understood as reliability of manufacturer's declaration of composition of offered dietary supplements, is highly important. We have tested 22 products available in pharmacies and supermarkets, manufacturers of which declared content of n-3 fatty acids (21 dietary supplements and I drug). Identity and content of DHA and EPA were assessed using ¹H NMR spectroscopy, based on characteristic signals from protons in methylene groups. Almost one in five of the examined dietary supplements contains < 89% of the PUFA n-3 amount declared by its manufacturer. For a majority of tested products the manufacturer-declared information regarding DHA (58%) and EPA (74%) content was consistent with the actual composition. It is notable that more cases of discrepancy between the declared and the actual content regarded DHA than EPA, which indicates a less favorable balance, considering the pro-health effect of those acids. Over a half of tested products provides the supplementary dose (250 mg/day) with one capsule taken daily, and in 27% of cases the daily dosage should be doubled. Only 10% of those products ensure the appropriate dose for cardiovascular patients (1 g/day) with the use of I capsule a day. Correct information provided by a manufacturer on a label regarding the total amount of DHA and EPA is a basis for selection of an appropriate dosage.