Composition and quality of marine Omega-3 supplements on the Russian and Norwegian markets: a comparative study.

Abstract

The possible health effects of the long-chain Omega-3 fatty acids, eicosapentaenoic (EPA; 20:5 n-3) and docosahexaenoic (DHA; 22:6 n-3) have been studied for the last 40 years. The outcome of these studies has shown that intake of these Omega-3 may reduce risk of death from cardiovascular disease and possibly also have anticancer effects, improve brain development, reduce depression and delay the beginning of Alzheimer’s disease. The reference daily intake for EPA+DHA is 500 mg and it is advised to obtain this quantity from fish. Omega-3 supplements or functional foods with added Omega-3 fatty acids could be an alternative for people with low consumption of fish. Supplements containing long-chain Omega-3 fatty acids reached $33 billion in global sales in 2012 with an annual growth rate for the period of 2007-2012 equal to 12%. An increase in reliability of producers within quality and safety issues is essential in a way to obtain fisheries management goals, sustainable use of marine resources and maximizing of benefits for all involved. Composition of a product claimed on the label is the one of the main criteria for consumers in a product choice and evaluation of benefits. The overall aim of the thesis was to compare the composition and quality of marine Omega-3 supplements on Russian and Norwegian markets by accomplishment of the following tasks: 1. Determination of fatty acid composition of the products by gas chromatography and comparison with the specifications given on the products labels; 2. Analysis of lipid classes by high performance thin layer chromatography and comparison with the specification given on the products labels. Thirteen products (7 Russian and 6 Norwegian) were analyzed. The Russian products contained triacylglycerols and generally had a low concentration of long-chain Omega-3 fatty acids. All the supplements were declared as fish oils, but, in fact, 4 of them contained plant oils resulting in an increased n-6/n-3 ratio. The Russian product descriptions had no information about the amount of oil in capsules or quantity of EPA and DHA. The recommended intake for 5 of the 6 capsule products was high, from 9 to 24 per day. The Norwegian capsule products (5) were mostly concentrated supplements containing up to 71% of long-chain Omega-3 fatty acids, either in the form of ethyl esters or triacylglycerols. Information about content of Omega-3 fatty acids and EPA and DHA was included on the labels. However, information about oil amount in capsule was lacking for one product. The analysis suggested that the specification with regard to the lipid class form was not always precise. Two products were described as native marine oils, but the analysis showed that they contained ethyl esters. Claimed and found content of Omega-3, EPA and DHA, were slightly different for one product, up to 39% lower for 3 products and higher for one supplement. Daily intake of 2 capsules on the average met the recommended daily intake of 500mg of EPA+DHA. The average price per gram of Omega-3 was approximately the same for the Russian and Norwegian products.