Mead acid, a 20-carbon ω-9 polyunsaturated fatty acid, experiences elevated levels in human plasma under conditions of essential fatty acid deficiency. As 1,25(Z),8(Z),11(Z)-Eicosatrienoic Acid methyl ester (Mead acid methyl ester), it frequently serves as a standard for fatty acid analysis, particularly after fatty acids have been transesterified into methyl esters.