Breath hydrogen test for detecting lactose malabsorption in infants and children. Prevalence of lactose malabsorption in Japanese children and adults

Arch Dis Child. 1979 Jun;54(6):436-40. doi: 10.1136/adc.54.6.436.


The breath hydrogen test (BHT) was adapted for use in young infants and children. The diagnostic criterion of sugar malabsorption in the BHT was determined by oral administration of 0.5 g/kg of unabsorbable sugar (lactulose) to 21 healthy infants and children. A maximum increase in breath hydrogen less than 0.05 ml/min per m2 was observed in all subjects. A good correlation between results by the BHT and by the ordinary lactose tolerance test was obtained after oral administration of 2 g/kg lactose to 21 healthy infants and children, 2 congenital lactase-deficient infants, and 7 adults. Using this test, 80 healthy Japanese infants and children (aged between one month and 15 years) and 18 adults were examined for lactose malabsorption after a dose of 1 g/kg lactose. All infants and children under 2-years old absorbed lactose completely. The incidence of lactose malabsorption was 30% in 3-year, 36% in 4-year, 58% in 5-year, and 86% in 6-year-old children, 85% in schoolchildren, and 89% in adults. Thus the incidence of lactase deficiency gradually increases with age from 3 years, and about 90% of all normal Japanese adults are lactase-deficient.

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Blood Glucose
  • Breath Tests / methods*
  • Child
  • Child, Preschool
  • Humans
  • Hydrogen / analysis*
  • Infant
  • Japan
  • Lactose Intolerance / diagnosis
  • Lactose Intolerance / epidemiology*
  • Middle Aged


  • Blood Glucose
  • Hydrogen