Lactase deficiency: Distribution, associated problems, and implications for nutritional policy

Abstract

Lactase deficiency is highly correlated with lactose malabsorption, as determined by standardized testing procedures, and to a lesser extent with lactose intolerance, as determined by symptoms resulting from the ingestion of lactose. Rates of lactase deficiency vary considerably among populations. The literature on the distribution of lactase deficiency is reviewed, followed by a discussion of associated dietary problems and health problems. Because lactase deficiency tends to have a high prevalence rate among ethnic minority groups in the U.S. and among native populations in the Third World, food supplementation programs that include milk which are provided for those groups may not achieve the intended results. Implications of the distribution of lactase deficiency for nutritional policy are presented, and the alternative of providing a lactose‐free milk substitute is discussed.