PREVALENCE OF LACTOSE-MALABSORPTION IN GALICIA

Background: The aim of the current study was to evaluate the prevalenc e of lactose malabsorption (LM) in Galicia (NW Spain) in order to desi gn nutritional intervention and/or public education strategies for hig h risk groups. Methods: We conducted a study of LM by breath-hydrogen carbohydrate absorption test (BH2 test) in 850 healthy subjects. All s ubjects underwent BH2 tests following ingestion of a aqueous solution of 2 g lactose/kg body weight up to a maximum of 50 g. Subjects with L M were retested after ingesting 250 ml of milk and/or 250 ml of yogurt . Results: The frequency of LM in the subjects who ingested 2g lactose /kg body weight was 32.5%. This percentage decreased significantly wit h a decrease in the quantity of administered lactose and the vehicle w as milk or yogurt-only 13.7% was LM after 250 ml of milk and 3.8% afte r 250 ml of yogurt. Gastrointestinal symptoms also depend on dosage of lactose and vehicle, decreasing from 54.3% after 2g lactose/kg to 18. 5% after milk and to 0% after yogurt. The frequency and number of gast rointestinal symptoms were significantly higher (p < 0.001) in LM than in lactose absorption (LA). Conclusions: Lactose malabsorption is pre valent in the population of Galicia. An important number of subjects i dentified as LM with usual clinical testing become LA when the ingesti on of dairy products is limited so that the amount of lactose consumed is similar to that contained in a usual serving. Our results su est t he importance of BH2 testing following ingestion of usual consumed amo unts of lactose per serving. (C) 1997 Lippincott-Raven Publishers.