The article in this issue of the Journal by Paxson, Adcock, and Morriss (see p 139) directs the reader's attention to the variability in the osmolality of commonly used formulas. Further, it reminds us that notable differences in concentration exist either due to the variation among lots from a single manufacturer or due to alterations in the method of reconstitution. Formulas prepared by the use of a scoop may have an osmolality approaching twice that of the same formula reconstituted by weight per the manufacturer's formulation. Such differences in composition are certain to alter the response to the infant, particularly the low-birth-weight infant, to his feedings. Although the article by Paxson et al examines some formulas that would not ordinarily be used by physicians in the care of low-birth-weight infants, the consequences of using these formulas must be recognized.
The observation that formulas, especially those reconstituted through the use of
SEGAR WE, CHESNEY RW. On Certain Physical-Chemical Properties of Infant Formulas. Am J Dis Child. 1977;131(2):137-138. doi:10.1001/archpedi.1977.02120150019001