Mature milk is different in that the intracellular junctions become tighter and we have less leakage of blood components (live cells etc) into the milk.  That's why in Hale's book he talks about how some research done on drugs passing into milk is incorrect because done on a weaning breast where junctions have become looser with lower synthesis of milk.  I think that as with any human research, carefully designating your population and describing its characteristics is so important.  The age of the baby, the exclusivity of breastfeeding, hormones mom is taking, diet, etc should ALL be taken into account.  I can't overemphasize to moms that you are not a Chevy and you cannot go to Autozone and just buy a new carburator!  Human beings are complex and adaptable.  They are not like my webiste or my computer where you mess up on one character and the whole thing blows! 

-----Original Message-----
From: Lactation Information and Discussion [mailto:[log in to unmask]] On Behalf Of Sam
Sent: Saturday, August 22, 2009 7:11 PM
Subject: Re: re not two kinds of milk

Does that also include the thought that colostrum really only differs from mature milk in that mature milk is more dilute? 

Sam

<<

Yes, the breasts only make one kind of milk.
If I remember correctly, a paper from the Hartmann team (Lean Mitoulas, I
think) stated that it was volume of milk over 24 hours, rather than fat content, that determined the amount of calories the baby received.
The fat molecules travel back up the breast between feeds.  The shorter the interval between feeds, the higher the fat content of the "foremilk".  The fat globules adhere to the ductules and are dislodged as the feed progresses.

Jean Ridler  RN  RM  IBCLC
South Africa   [log in to unmask] >>

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