The omegas: A long, scaly tale, still growing

The discovery of polyunsaturated fatty acids’ (PUFA) essentiality for human health opened the 20th century and has now outlasted it. The late biochemist Ralph Holman was among the great scientific bridges between the first generation of “vitamin F” researchers and the present generation of professionals in the science and technology of the “omegas.”¹ He coined that latter term in the 1960s as requirements for the omega-6s were recognized, although we were still decades away from an understanding of the needs for omega-3s.

In general, the first half of 20th century was an era of scientific revolutions. Historians of science write about Albert Einstein’s miracle year, 1905, when he bent the complacent world of Isaac Newton’s physics to the global reach of the quantum and the reference frame. In biology, for the 50 years after Louis Pasteur’s discovery of pasteurization, medicinal experts assumed pathogenic bacteria were the cause of all diseases, including the intractable scourges of pellagra (niacin deficiency), beriberi (thiamin deficiency), scurvy (ascorbate deficiency), and many others that ran rampant in the industrializing world. It was names like Christiaan Eijkman, Kazimierz Funk, Frederick Gowland Hopkins, Albert Szent-Györgyi and Joseph Goldberger who introduced the concepts of trace dietary components whose absence causes frank disease. These “vitamins” have now transitioned from the dismissed to the obvious.

In physics, the scientific pioneers’ names pass into legend. In nutrition, the scientific pioneers’ contributions pass into common knowledge.

The story of the discovery of essential fatty acids (EFAs) is generally credited to George and Mildred Burr working in the attic of the plant science building in the University of Minnesota examining skin lesions in rats on fat free diets.² Their 1929 paper on the topic led to the discovery of omega-6 fatty acids that prevent scaly skin and are required for proper skin barrier function. The concept of a vitamin F required for the skin was key to establishing dietary requirements for omega-6 in humans by the 1960s.³ Yet back then, so clear were the manifestations of omega-6 deficiency, and so subtle the symptoms of omega-3 deficiency, that few in medicine recognized the scientific hallmarks of omega-3 as a required nutrient.

Moving ahead a few decades, docosahexaenoic acid (DHA) was recognized by Klenk and Holman as especially prominent in the pig brain in the 1950s,⁴ and Sinclair and Crawford recognized it in all brains⁵ around the time Gene Anderson showed it as essential for retinal function (1970s).⁶ However, it was not until the 1980s that omega-3s were widely understood to be required for neurocognitive health.³ Eicosapentaenoic acid (EPA) was the first miracle omega-3, reducing cardiovascular disease risk, identified from studies in the natives of northern Canada in the late 1970s.⁷ The pendulum swung back to DHA in the 1980s and 1990s with animal deficiency studies⁸ complementing human clinical science demonstrating effects of dietary DHA on retina⁹ and brain development in infants.¹⁰ EPA has now joined in again, with human clinical trials consistently showing it is required for avoidance of depression in some.¹¹

The expanding tools of modern biology have enabled clarification of the genetics and interconnected metabolism of omega-3 and omega-6 in our millennium. Our era of personalized health is first facilitated by nutrition of key nutrients, none more important than EPA and DHA.

Tom Brenna is a professor in the department of pediatrics at the University of Texas at Austin, and a professor emeritus in the division of nutritional sciences at Cornell University, Ithaca, New York.

Brenna is speaking on “Historical Perspectives on Omega-3s” at the GOED-Exchange, Feb. 4 to 4 in Barcelona.

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