Your suspicion of why a formula company might try this (connection between formula feeding and obesity) certainly rings true to me!
You inspired me to turn to Google, and after reading this, it makes me worry that the very "single simplistic point" premise the rep is presenting may be designed to "set you up" in front of your staff for any "arguments" you may present. Nevertheless, there seemed to be a lot of good info and good insight in this link:
http://www.parentingscience.com/calories-in-breast-milk.html
Hope this is helpful. This was just near the top of the list when I put in: "measuring kcal in breast milk". I encourage you to continue the Google search.
K. Jean Cotterman RNC-E, IBCLC
WIC Volunteer Dayton OH
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