Lactase deficiency in Australian school children

The prevalence of lactase deficiency is high in Mediterranean, Middle Eastern and Asian countries, which suggests that many immigrants and immigrant children from these regions may be unable to produce lactase. Therefore, the aim of this study was to determine the prevalence of lactose malabsorption in primary school-aged children, in two communities with a high proportion of immigrants in metropolitan Sydney. A total of 109 children, aged five to 12 years, were studied by means of the breath hydrogen method. Forty per cent (44/109) showed lactose malabsorption, as defined by a rise in end-expiratory hydrogen levels of 20 ppm or more, two hours after loading with lactose. The prevalence was highest in the subjects of Asian origin (93%; 14/15), followed by Greek subjects (56%; 14/25) and subjects from other Mediterranean and Middle Eastern countries (41%; 15/37). Of the 77 children who were available for follow-up, 57% (44) reported symptoms of lactose intolerance, of whom nearly two-thirds were children who showed lactose malabsorption. The high prevalence of lactase deficiency in children at both schools underlines the need to consider the multiracial identity of Australians in planning educational programmes about nutrition.