Variability of breath hydrogen excretion in breast-fed infants during the first three months of life

Breath hydrogen excretion was measured serially in breast-fed infants. There was marked variability in H2 excretion, both within and between infants. The findings indicate that unabsorbed food is not the only substrate, and that breath H2 may not be an effective method to assess carbohydrate absorption in young infants.