This is thought to be related to a human baby's rapid brain growth in infancy, compared to other mammals. Removing lactose from any baby's diet for more than a short period should not be done lightly, and only under medical supervision. Lactose overload Lactose overload can mimic lactose intolerance, and is frequently mistaken for it. An overload is commonly seen in babies consuming large amounts of breastmilk, ie in mothers with an oversupply. This may result in symptoms such as an unsettled baby with adequate to large weight gains, more than ten wet and many dirty nappies in 24 hours.
Baby is usually less than three months old.
Ironically, a mother may perceive that she has a low supply because her baby always seems to be hungry. The nappy count can be the biggest clue to what's happening. The lactose reaching the lower bowel draws extra water into the bowel, and is fermented by the bacteria there producing gas and acid stools. The latter often causes a nappy rash. Sucking is the best comfort he knows, and helps move the gas along the bowel.