The identification of essential fatty acids by George and Mildred Burr in 1929

The discovery of essential fatty acids (EFAs) by George and Mildred Burr in 1929 was a transformative moment in nutritional science. Before their groundbreaking work, dietary fats were seen primarily as a source of energy, largely interchangeable with carbohydrates. The Burrs’ meticulous research demonstrated otherwise, revealing that certain fatty acids were indispensable for health.

Using rats as their model organism, the Burrs conducted a series of controlled experiments that involved feeding the animals fat-free diets. The results were striking: the rats exhibited poor growth, developed scaly skin lesions, and eventually succumbed to their ailments. The symptoms were reversed when the rats were supplemented with specific fats, leading the Burrs to identify linoleic acid—a polyunsaturated fatty acid—as essential for life. This discovery not only redefined the role of fats in nutrition but also challenged the prevailing view that fats served solely as a source of calories.

The implications of the Burrs' work extended far beyond the laboratory. Their research laid the foundation for the concept of EFAs, a class of nutrients critical for maintaining numerous physiological functions. EFAs, including linoleic acid (an omega-6 fatty acid) and alpha-linolenic acid (an omega-3 fatty acid), are now recognized for their roles in maintaining cell membrane structure, regulating inflammation, and supporting brain and retinal development. Deficiencies in EFAs have been linked to various health issues, including immune dysfunction, cardiovascular diseases, and neurodevelopmental disorders.

Modern research has expanded on the Burrs' findings, uncovering the broader significance of EFAs in human health. Omega-3 fatty acids, for instance, are now celebrated for their anti-inflammatory properties and their potential to reduce the risk of chronic conditions such as heart disease, arthritis, and depression. The role of EFAs in prenatal and early childhood development has also been emphasized, with dietary guidelines recommending adequate intake of these nutrients during pregnancy and breastfeeding.

The discovery of EFAs by George and Mildred Burr not only revolutionized nutritional biochemistry but also reshaped public health policies and dietary recommendations. Today, their work continues to inspire research into the complex roles of fats in human health, underscoring their importance in a balanced diet. This seminal discovery remains a cornerstone in our understanding of the intricate relationship between nutrition and well-being.
The identification of essential fatty acids by George and Mildred Burr in 1929

George O. Burr

History and discovery of fatty acids

Modern concept of fats are due to the French chemist, Chevreul who investigated the chemistry of animal fats between 1810-23. His work Recherches chimiques sur les corps gras d’origine animale appeared in 1823.

Essential fatty acid was discovered by husband and wife team, George and Mildred Burr at the University of Minnesota. In 1930 they identified linoleic and linolenic acids as essential for growth and reproduction.

They reported that linolenic acids a fatty acid of exclusively plant origin, cured a diseases condition observed in rats.

They fed the rats fat free diets and found that they developed a whole range of symptoms, including skin lesions, decrease in body weight, and heart and kidney enlargement.

The invention of the gas chromatography by James and Martin in the 1950s was milestone for lipid chemistry. At that time it was used for the separation of normal carboxylic acids up to 12 carbon atoms in chain length.

A few years later James and Martin themselves developed the method of separating fatty acids as their methyl ester derivatives, thereby preparing the basis for modern fatty acid research.

The first gas-liquid chromatographic analysis of milk fatty acids was published by James and Martin in 1956.

In 1953 Cropper and Heywood extended the method to the separation of the methyl esters of even-numbered fatty acids up to behenic acid.

By 1960, may laboratories were using GLC for routine analysis of fatty acids.
History and discovery of fatty acids