Giving Fatty Acids Their Due

I NOTE THAT in “Devising Healthier Foods,” omega-3 and omega-6 fatty acids—a subdivision of polyunsaturated fatty acids (PUFAs)—were not adequately discussed (C&EN, June 23, page 12). Both types of fatty acids are polyunsaturated, but they have very different effects on the body. These are essential fatty acids in the diet, and the ratio of the fatty acids in the body determines overall health. These fatty acids are second messengers (eicosanoids) and have an effect on every cell in the body. A wide range of chronic diseases are implicated with a decreased ratio of omega-3 to omega-6 fatty acids.

Current research has established that omega-3 fatty acids are anti-inflammatory and omega-6 fatty acids are inflammatory in nature, and that increasing the amount of omega-3 fatty acid intake relative to omega-6 fatty acids is beneficial for cardiovascular conditions and for reducing inflammation. Numerous references to this topic are in the literature, and the intake of fish oil (containing primarily omega-3 fatty acids) as a supplement has gained broad popularity in the public in recent years. The two key omega-3 fatty acids present in fish oil are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

Numerous foods are fortified with omega-3 fatty acids, and active research is devoted to increasing the levels of omega-3 fatty acids in food sources. A recent paper by Sandersen et al. of Wageningen University, in the Netherlands, revealed through a nutrigenomics study that dietary unsaturated fatty acids govern a huge number of genes. DHA had the most significant impact. Current news includes preparing DHA from algae fermentation (Martek Biosciences) and an agreement between Dow AgroSciences and Martek to jointly develop a canola seed that produces DHA.

In summary, due to the importance of these compounds to health and considering the large number of research articles devoted to omega-3 and omega-6 fatty acids, a discussion of devising healthier foods is remiss unless these compounds are also considered.

Thomas McNabb
Arlington, Tenn.