Another thought, how about the confounding factor that BF babies get fewer
infections in the first year?

Personal experience, my 5th baby had major allergy problems in 1st 7 mo.
Asthmatic bronchitis and pneu., which all greatly improved when I stopped
drinking milk.  He's allergic but we never moved on to full fledged asthma.
 And my 13 y.o. grandson, exclusively BF who reacted wildy to mom's dairy
intake as an infant (which she stopped) who has developed asthma in past
few years.

Sincerely, Pat in SNJ