Lactose malabsorption in Khants in western Siberia.

Background: We wanted to estimate the prevalence of selective lactose malabsorption (SLM) in Khants, a small Finno-Ugric population living in Western Siberia who have traditionally consumed no milk in adulthood.

Methods: A total of 80 Khants, aged 8-57 years and living on the middle reaches of the River Ob, were studied. The diagnosis was based on a lactose tolerance test; general malabsorption was excluded by a glucose-galactose tolerance test whenever possible. In six subjects electronmicroscopic examination of the duodenal mucosa was performed.

Results: The prevalence of SLM in the Khants was 94%.

Conclusion: This is the highest prevalence found in the previous Soviet Union.