Hello,
     I attended a great lecture by Dr. Karin Cadwell a month ago.  She says
the studies on use of ABM as a supplement to breastfed babies shows that the
iron in the ABM supersaturates the lactoferritin in breastmilk and makes it
disfunctional in carrying the iron in the breastmilk across the cell membranes
in the gut.  Thus when you mix ABM with EBM, effectively, the baby gets very
little iron or it gets some that is not bound to the lactoferritin.  How iron
gets into the gut of exclusively formula fed babies is by diffusion.  The
concentration of iron (in the formula) in the gut is higher than in the cells
or the blood stream so the iron moves to the place of lower concentration to
equal the concentration gradient.  This is why ABM needs to have such an high
concentration of iron, because it does not contain lactoferritin which is the
protein carrier of the iron in breastmilk and transports it accross the gut
and into the blood stream.  So if a breastfed baby is going to be supplemented
with formula it should be exclusively formula or exclusively breastmilk per
meal.  There has been some discussion about using the low iron formula to
supplement a breastfed baby but I am unsure of any studies on this.  The
effect may be the same.
     The other very eye opening info she gave is that the pH of a breastfed
babies gut is 5.  The pH of a formula fed babies gut is 8.  This pH difference
allows for the breeding of unfriendly bacteria, like e.coli, bacteroides,
clostridium etc. in the gut of the formula fed infant and poor function of any
immunoglobulins.  Where as the pH of 5 allows for breeding of friendly
bacteria like lactobacillus acidophillus, bifidus and bulgaris.  Also, the
immunoglobulins work perfectly in this acid environment.  One bottle of
formula in the breastfed babies gut turns the pH to 8 for up to 6 weeks, just
one bottle!  Also, formula especially soy destroys the normal configuration of
the villi in the gut from nice flowery villi to flat stubby ones which
decreases the absorption and assimilation ability of the gut as a whole.
     If you ever get the chance to attend a lecture by Dr. Karin Cadwell leep
at the chance.  She has studied all the research on human milk, lactation and
breastfeeding and formula feeding.  It is very insightful.  Too bad the people
who need to know the information like parents and healthcare professionals are
the last to know but that is changing!

                                                                     Sincerly,
                                                                     Cynthia
S. Marske DO