Human milk lipids – what do we know?

Presented by Dr. Johann Demmelmair on Tuesday, Nov 3, 2020.
Fat occurs in human milk as milk fat globules and provides about 50% of human milk energy. Although more than 200 fatty acids have been identified in human milk, there are only a limited number of fatty acids with quantitative relevance, but these form a huge number of different lipids. Non polar triglycerides, which contribute more than 98% -wt/wt to the fat, form the core of the milk fat globules. Specific for milk fat is a relatively high content of short and medium chain fatty acids with up to 14 carbon atoms and a strong enrichment of palmitic acid at the sn-2 position. Both factors enhance fat digestibility. Of importance is the content of the essential fatty acids and their long chain polyunsaturated derivatives. They are mainly provided by triglycerides, although their relative percentage may be higher in certain more polar milk lipid fractions. The polar lipids in milk include glycerophospholipids, sphingolipids, and cholesterol. Quantitatively they are all minor components, but their importance for the development of the infant digestive tract, immune system and cognition has started to be recognized in recent years.