Formula Fantasies - a favorite topic of mine! Standard infant formulas made from cow's milk must have the butterfat in them removed because butterfat is poorly absorbed in human babies. Plant fats are substituted and are typically blended to provide somewhere between 45%-58% of the energy intake. Corn oil, coconut oil, palm oil, safflower oil, etc are used to provide varying amounts of numerous fatty acids. They are a cheap source of well absorbed fats. Fatty acids are the building blocks of fat, just like amino acids are the building blocks of protein. These blended fats however, do not contain the very long chain polyunsaturated fatty acids (LCPUFA)so prevalent in the human brain and retina. Human milk of course contains these fatty acids. Two of these LCPUFA, called docosahexaenoic acid (DHA) and arachidonic acid (AA) are currently the subjects of scads of papers on whether these should be designated as essential in the diet of infants. DHA is the fatty acid which is thought to be responsible for the better cognitive functioning in breastfed infants. In the advertising of infant formula you will never see these two fatty acids mentioned because they do not occur in any US formula. They have been added to some formulas in Europe. These fatty acids were derived from marine algae, not human sources! Several review articles are quite specific in that "...there is little doubt that there is a short term effect of DHA deficiency on efficiency of synaptic transmission during a critical period of brain development and learning." Formula fed babies also lack cholesterol in their feeds. All this fat is what forms the myelin sheath around nerve tissue. If babies do not receive DHA and AA directly from their diets then they need to make it. Most term babies and all preterm babies cannot do this. The brains of formula-fed babies substitute shorter chain fatty acids in place of the LCPUFA. The chemical composition of the brains are different. Formula companies may advertise how close their concoctions are to breastmilk, but even the fake DHA/AA stuff had problems in clinical trials. This stuff must be in the proper ratio. Early trials of the fake LCPUFA experimented with not only the source of the fatty acids but also the ratio. Some of the babies who received the experimental formulas with too much AA scored significantly lower on cognitive tests at one year of age than the controls and the other experimental groups. Why do commercial interests think they can duplicate human milk? How many babies have been harmed in these clincal trials? At least they got all the test formulas for free.