Why a Human Milk Project? Human milk fat has a unique fatty acid composition. It is approximately 45 to 50 percent saturated, about 35 percent monounsaturated and 15 to 20 percent polyunsaturated. Of the saturated fatty acids made in the mammary gland, up to 18 percent can be the antimicrobial fatty acids lauric acid and capric acid. These antimicrobial fatty acids give the infant protection against viruses such as HIV and