Freshwater fish - an important source of n-3 polyunsaturated fatty acids: a review

Abstract

In addition to n-6 fatty acids, n-3 polyunsaturated fatty acids are essential ingredients of the human diet. Many marine fish contain high levels of these fatty acids; however, freshwater fish are also an important source of n-3 fatty acids, especially eicosapentaenoic and docosahexaenoic acids. Generally, there is a balanced relation between n-3 and n-6 fatty acids in freshwater fish. Just as other animals and humans, fish cannot synthesize the essential fatty acids of the n-6 and n-3 series. Thus, these fatty acids must be supplied by the diet, and their original source is plants, particularly phytoplankton. The fatty acid composition of fish is strongly influenced by the lipid pattern of their food. Feeding high energy diets containing high amounts of fish oil in aquaculture results in marketable fish with substantial levels of n-3 polyunsaturated fatty acids. Several investigations have shown that the consumption of freshwater fish has beneficial effects on human health, especially for persons suffering from cardiovascular diseases. This is why freshwater fish is recommended as wholesome food for humans.

CORRESPONDING AUTHOR:

Prof. dr. habil. Werner Steffens, Eitelsdorfer Str. 32, D-12555 Berlin, Germany, Tel./Fax: +49 30 6561390;
e-mail: w.l.steffens@t-online.de