There is no substitute for breast-milk for infants. ZERO TOLERANCE. But if there is not option and it becomes mandatory (due to mother’s inability to lactate), do not ever try Soy based formula. If you are using it, stop it! Instead, find genuine desi Gau-milk (You should know how to identify cow) in vicinity and use it. (I know parents who regularly travel 60 kms+, just to get pure gau milk for infants of friends and relatives)
Why not soy milk formula?
Soy foods contain trypsin inhibitors that inhibit protein digestion and affect pancreatic function. In test animals, diets high in trypsin inhibitors led to stunted growth and pancreatic disorders. Soy foods increase the body’s requirement for vitamin D, needed for strong bones and normal growth. Phytic acid in soy foods results in reduced bioavailabilty of iron and zinc which are required for the health and development of the brain and nervous system. Soy also lacks cholesterol, likewise essential for the development of the brain and nervous system. Megadoses of phytoestrogens in soy formula have been implicated in the current trend toward increasingly premature sexual development in girls and delayed or retarded sexual development in boys.
Currently about 25 percent of bottle-fed babies, according to the American Academy of Pediatrics—are on soy-based diets because they rarely receive anything else to eat, which has led the Israeli Health Ministry, the French Food Agency, the German Institute of Risk Assessment, and the British Dietetic Association to warn parents and pediatricians that soy formula could jeopardize brain and body development and should be used only as a last resort.[1],[2]
[1]. For more information about the Israeli warning
[2]. Book : Daniel, Kaayla T. The Whole Soy Story