Some of us who publish on breastfeeding prefer to use the single
run-together word but keep bottle-feeding as a hyphenated word to reflect
it's artificialness.  Bottle-feeding is "feeding with a bottle" but
"breastfeeding" is much more than "feeding with a breast" -- it's also
immunological help, emotional comfort, warmth, good mom smells, etc.  I
can't really think logically now about why taking the hyphen out makes
breastfeeding "mean" all these other things, too, but we definitely are
trying to make a statement that the two things are NOT equivalent.
Katherine A. Dettwyler, Ph.D.
Associate Professor of Anthropology
Texas A&M University
co-editor of "Breastfeeding: Biocultural Perspectives" and specialist in
infant feeding and growth
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