Running head: Lactose (mal)digestion
نویسندگان
چکیده
Background: The prevalence of genetically determined lactase non-persistence is based on the results of the lactose H 2 breath test. This test, however, is an indirect test, which might lead to misinterpretation. Design: We determined lactase activity in healthy Chinese and Dutch students using a novel C-lactose digestion test. The cut-off value of this test was established in a Chinese population with a homogenous genetic background of lactase non-persistence and was compared with the results obtained in a Caucasian population. Twenty-five grams of a C-lactose solution was consumed by 12 known H 2 -positive and 5 H 2 -negative Chinese students and 48 Dutch students and, subsequently, C-glucose concentration in plasma and H 2 excretion in breath were measured. Results: A similar C-glucose response curve was found in all Chinese students. The mean response curve in the Dutch students was more pronounced (P<0.01). The 1 h (peak) plasma C-glucose concentration was the best discriminator between lactose digesting and maldigesting subjects. The cut-off level of 2 mmol/L C-glucose in plasma was defined in the H 2 -positive Chinese students group. Based on the C-glucose response, the prevalence of lactose maldigestion in the Dutch subjects was 25%; based on the lactose H 2 breath test 17%. Conclusions: Using the C-lactose digestion test, the results demonstrate a higher prevalence of lactose maldigestion in a Caucasian population than indicated by the results of the H 2 breath test. A moderate increase in the plasma Cglucose concentration after consumption of C-lactose in the young adult Chinese subjects indicates a residual lactase activity in that age group, even when a positive H 2 breath test result is obtained. These results indicate that the Cglucose concentration in plasma more accurately reflects the small intestinal lactose digestion capacity than the lactose H 2 breath test.
منابع مشابه
Phylogenetic analysis of the evolution of lactose digestion in adults. 1997.
In most of the world's population the ability to digest lactose declines sharply after infancy. High lactose digestion capacity in adults is common only in populations of European and circum-Mediterranean origin and is thought to be an evolutionary adaptation to millennia of drinking milk from domestic livestock. Milk can also be consumed in a processed form, such as cheese or soured milk, whic...
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