Australian food sources and intakes of omega-6 and omega-3 polyunsaturated fatty acids

Both omega-6 and omega-3 polyunsaturated fatty acids (PUFAs) are recognised as essential nutrients in the human diet, yet we have little information on the extent to which different food sources contribute to their intake. The aim of the present study was to ascertain the daily intakes and food sources of omega-6 and omega-3 PUFAs in our local community.

Three-day food records were obtained from 83 healthy adults living in the Illawarra region of New South Wales. The PUFA composition of the foods which they consumed was derived from food composition tables and recently published food analysis data.

Polyunsaturated margarine, nuts/seeds, bread, snacks/desserts and takeaway foods were important sources of omega-6 PUFAs, while canola oil and margarine, takeaway foods, snacks/desserts and bread were sources of alpha-linolenic acid (LNA), an omega-3 PUFA. As expected, fish was the main source of the very long chain (VLC) omega-3 PUFAs, i.e. eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA), to which significant health benefits are attributed. An unexpected finding, however, was that, due to the large amount eaten, meat was also a major contributor (29%) to the dietary intake of VLC omega-3 PUFAs. Median intakes of omega-6 and omega-3 PUFAs were 9.9 and 1.2 g/day, respectively, resulting in a dietary omega-6:omega-3 ratio of 8:1. The median intake of VLC omega-3 PUFA was 0.18 g/day.

We have identified food sources and intakes of PUFAs for an Australian subpopulation differentiating between omega-6 and omega-3 PUFAs. Whilst canola and fish were the primary sources of LNA and VLC omega-3 PUFAs respectively, we found that meat made a significant contribution to VLC omega-3 PUFA intake.