Lactose malabsorption in Turkish schoolchildren

The frequency of adult-type lactose malabsorption and the starting age were investigated in 334 healthy school children. After an fasting overnight each pupil emptied his/her bladder then drank a solution containing 2 g lactose per kg of body weight. Urinary galactose concentrations in the samples taken at the end of the second hour were measured with a galactose-dehydrogenase kit (Galactest, Boehringer Mannheim). A urinary galactose level of less than 0.9 mmol/L was taken to indicate hypolactasia. Lactose malabsorption was determined to be progressively higher with age; 44% at 7, 84% at 14 and the overall average for school-age children was 62%. Frequency of lactose malabsorption showed a linear increase with age. Lactose intolerance symptoms were observed in two thirds of the malabsorbers, wile the same symptoms were found in 30% of children without the malabsorption. The lactose absorption test by determining galactose excretion in urine is an easy and non-invasive screening method.