Lactose absorption and malabsorption in healthy italian children: Do the quantity of malabsorbed sugar and the small bowel transit time play roles in symptom production?

Using breath hydrogen analysis after an oral lactose load (2 g/kg; maximum 50 g), we investigated the prevalence of lactose malabsorption in 61 healthy Italian children aged 6-13 years. We also examined the relationship between symptoms and small bowel transit time and the degree of sugar malabsorption. Three of 61 subjects produced no H₂after both lactose and lactulose load and thus were eliminated at the outset. Lactose malabsorption was defined as excretion of >20 ppm H₂. Lactose intolerance was classified as mild (colicky pain, flatulence, abdominal distension, borborygmi) or severe (diarrhea). The frequency of lactose malabsorption in the children aged 6-8 years (group I) was 25%; in the children aged 8-11 years (group III), it was 35%, and in the found no difference in the small bowel transit times or in the quantities of malabsorbed lactose in symptomatic and asymptomatic mal-absorbing subjects. Other factors that may play a role in symptom production are discussed.