Regarding the posting about the acid in baby's saliva causing sore nipples:
from "Principles of Biochemistry" by White, Handler & Smith:
pH of saliva ranges from 6.4 - 7.0, where 7.0 is neutral.  This means
that saliva is an extremely weak acid in the chemical sense.
For comparison:
sweat:  pH 4.5 to 7.5 (generally more acidic than saliva)
tears:  pH 5.2 to 8.3
tapwater generally about pH 5.5 because of dissolved carbon dioxide
Remembering basic chemistry - below 7.0 is acid, above 7.0 is basic.

Sarah Friend Barnett, LLLL, IBCLC
Bronx (New York City), New York
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