Primary adult lactose malabsorption in Italy: regional differences in prevalence and relationship to lactose intolerance and milk consumption

Abstract

A study of regional differences in prevalence of primary adult lactose malabsorption in Italy was conducted on 205 subjects. Their origin was determined by their grandparents' birthplace, 89 from northern, 65 from central, and 51 from southern areas of Italy. Lactose malabsorption was diagnosed with standard oral lactose tolerance test and blood glucose determinations. Lactose malabsorbers showed symptoms more frequently than absorbers after the test load of lactose (p less than 0.01) they also reported milk intolerance more frequently (p less than 0.01). Prevalence of lactose malabsorption is significantly lower in the central sample (19%) than in the northern (52%) and southern (41%) samples (p less than 0.01). This finding contrasts with the hypothesis of a continuous increase in frequency of lactose malabsorption from northern to southern Europe and is probably due to the complex genetic history of the Italian population.

The diet of nineteenth‐century Greek sailors: An analysis of the log of theKonstantinos

“…Geographers and physicians have identified the genetic basis for adult human lactose intolerance or lactase deficiency (Simoons 1954(Simoons , 1969(Simoons , 1970(Simoons , 1971(Simoons , 1973Simoons, Johnson, and Kretchmer 1977). A considerable body of medical literature over the past twenty years has reported lactose intolerance in general (Buller and Grand 1990;Saavedra and Perman 1989) and for specific Mediterranean peoples, whether Arabs (Gilat et al 1971;Rotthauwe et al 1971;Snook et al 1976;Nasrallah 1979;and Hijazi et al 1983), Greeks (Doxiadis et al 1969;Spanidou and Petrakis 1972;Doxiadis and Papageorgiadis 1973;Kattamis et al 1973;Zografos et al 1973;Kanaghinis et al 1974;Ladas et al 1982;Ladas et al 1991), Italians (Burgio et al 1984;Cavalli-Sforza et al 1987), Jews (Gilat et al 1970;Leichter 1971), or Turks (Flatz et al 1986). 24.…”

Lactose and cataract in humans: a review.

“…These acquired and primary lactase deficiencies are to be distinguished, on the one hand, from the rare cases of congenital lactase deficiency which become manifest in the neonate as soon as milk is introduced into the diet and, on the other hand, from acquired impaired lactase activity secondary to nutrition al diseases or to diseases of the small intestine [37,38]. Patients presenting with an acquired or primary lactase deficiency may show evidence of intolerance to milk products [39]. However, clinical cases of lactose in tolerance are not all due to lactase deficiency [39,40].…”

“…Patients presenting with an acquired or primary lactase deficiency may show evidence of intolerance to milk products [39]. However, clinical cases of lactose in tolerance are not all due to lactase deficiency [39,40]. In fact, milk and milk products may be clinically well tolerated by subjects with lactase deficiency [41].…”

“…In addition, large varia tions in the incidence of lactose maldigestion in the same country may be encountered. An Italian report recently showed that the prevalence of lactose maldigestion varied from 10 to 25%, depending on the subjects' region of origin [39]. Intestinal lactase activity, upon which depends the quantity of galactose formed in the intestine, may be considered as an interindividual and interracial variable affecting the risk of cataract develop ment.…”

Dietary approaches to alleviation of lactose maldigestion / Efectos de la dieta sobre la digestión de la lactosa

“…Lactase deficiency is genetically determined. Man differs from other mammals in that some subjects continue producing lactase after infancy and throughout adult life (Cavalli-Sforza et al 1987). …”