Omega-3 fatty acids
Fish oil supplements contain the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Fish oils come from the flesh of some fish species, from the livers of other species, and also from krill (krill oil). Fish oils are not pure omega-3 but contain several other fatty acids. They also contain fat-soluble vitamins (Vitamins A, D and E); liver oils (e.g. cod liver oil) have more of vitamins A and D than fish body oils. Standard fish oils are about 30% EPA and DHA (combined). Fish oil concentrates have a higher content than this.
The likelihood of fish oils from reputable sources containing significant levels of contaminants (e.g. mercury) is low since the processing of fish oils for use in supplements removes contaminants if they are present in the starting oil.
Fish oil supplements have been used in a large number of trials in humans, many demonstrating positive effects on physiological functions, disease biomarkers and clinical outcomes. Omega-3 fatty acids have received several positive opinions from the European Food Safety Authority (EFSA).
There is a need for pregnant and nursing women to supply DHA to their baby to support brain and eye growth and development.
Intakes of EPA and DHA among adults in European countries are often quoted to average about 200 mg per day. However, these numbers represent the average intake of the small number of individuals who consume oily fish regularly and the large number of individuals who do not eat this kind of fish. An Australian study reported a median intake of EPA plus DHA of 30 mg per day (Meyer et al., 2003).
Recommendations for intake of EPA plus DHA to assure optimal health are typically in the range of a minimum of 200 to 500 mg per day. The FAO/WHO recommendation for adults is at least 250 mg EPA plus DHA per day (FAO/WHO, 2010), a recommended intake mirrored by EFSA (EFSA, 2010). Such intakes can be achieved by regular use of fish oil supplements.
However, higher intakes may be needed to influence some functions, such as inflammatory disorders or high blood lipids.
For further details on this topic please have a look at our article: „What you should know about fish oils and omega-3 fatty acids“
Meyer, B.J., Mann, N.J., Lewis, J.L., Milligan, G.C., Sinclair, A.J. and Howe, P.R. Dietary intakes and food sources of omega-6 and omega-3 polyunsaturated fatty acids. Lipids 38:391-8, 2003.
Food and Agriculture Organisation of the United Nations. Fats and fatty acids in human nutrition: Report of an expert consultation. Rome: FAO, 2010.
EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA); Scientific Opinion on Dietary Reference Values for fats, including saturated fatty acids, polyunsaturated fatty acids, monounsaturated fatty acids, trans fatty acids, and cholesterol. EFSA J 2010; 8: 1461.