Amazing infant nutrition facts

One often hears that infants have to eat frequently because they have small stomachs, but actually it's because they eat so much. Consider the following comparison.

An 8 lb. infant consumes about 3 oz. of milk every 3 hr., for a total of 24 oz. per day, about 500 calories, and gains about 1 oz. per day. (These figures are rough averages; there is a lot of variation among babies.) If we scale these figures by a factor of 20 for a 160 lb. adult, we find that you would have to drink about 2 quarts of milk every three hours for a total of 4 gallons per day, about 10,000 calories, and gain a bit more than a pound per day.

Some of this has to do with size. An 8 lb. adult cat needs about 250 calories per day. The extra 250 calories that the infant eats go straight into growing. 250 calories is just the energy in 1 oz. of fat that the baby might put on in a day.

Milk is, of course, mostly water, and Judy is drinking a bit more than a gallon of water a day to be able to provide for twins.

kdo@cosmos.phy.tufts.edu