This little book of 91 pages presents and discusses a multitude of measurements concerning breast milk. The quoted references total 235. The reader is impressed with how little we really know about breast milk because of the lack in uniformity of measurements and the great variety of conclusions. Wet nurses were used for many observations made a few decades ago.
Yield increases from the start of lactation for an uncertain time to a plateau of uncertain duration and slow decline. One study showed that milk yield is maintained against even severe reduction in water intake by economy of excretions by other routes. Excess fluid intake had no effect. Anxiety in the mother was mentioned, but its effects were not emphasized.
There is considerable day-to-day variation in all the constituents. Lactose is the most constant, fat the least; nitrogen varies somewhat, as do the minerals. The variations have little relationship to