Persistence of high intestinal lactase activity (lactose tolerance) in Afghanistan

Abstract

Two hundred and seventy apparently healthy adult subjects from Afghanistan, mainly from the central and eastern parts of the country, were subjected to a lactose tolerance test. The change of blood glucose from the fasting concentration at 20 min after the administration of lactose showed a bimodal distribution. Forty-seven subjects had a rise of blood glucose concentration of more than 1.1 mmol/l and were classified as persistence of high intestinal lactase activity (PHILA), a term which lays emphasis on the fact that high lactase activity in the adult is an unusual state whose prevalence in some populations requires explanation. In the Afghan sample there were no significant differences of the frequency of PHILA in different ethnic groups.

Prevalence of Primary Adult Lactose Malabsorption in Pakistan

“…India is also important because several lactose absorption studies in the northwestern part of the Indian sub continent, mainly the Panjab areas of In- dia and Pakistan, claim very low frequen cies of lactose malabsorption [6][7][8][9]. These findings are at variance with high frequen cies of lactose malabsorption in supposed ly related populations in Afghanistan [10], India [11] and in European gypsies [12,13]. The present study was undertaken with the aim of resolving these discrepan cies.…”

“…Therefore, milk consumption was, and still is low by European stand ards, and mostly in the form of heated or diluted sour milk products with low lac tose content. Similar milk consumption habits are characteristic of linguistically related populations in Afghanistan and Iran which exhibit high frequencies of lac tose malabsorption [10,29], It is improb able, therefore, that the comparatively low prevalence of adult lactose malabsorption in Pakistan is due to recent selection in fa vour of the lactase persistence allele. In troduction of lactase persistence by inter breeding with milk-dependent, nomadic groups of Southwest Asia is an alternative hypothesis which could be tested by lac tose absorption studies in these popula tions, e.g.…”

Measurement of breath hydrogen and methane, together with lactase genotype, defines the current best practice for investigation of lactose sensitivity

“…Therefore, the conventional terms 'lactose intolerant' or 'lactose tolerant' are clearly now erroneous. 3 As such, we have used the terms 'lactose sensitive' (LS) or 'lactose insensitive' in order to make our data clear. As a result, the current clinical management is inadequate due to failure in identifying how many patients have a low lactose threshold and what their individual sensitivity is.…”

Genetic Evaluation of Body Weight and Survival of Black Tiger Shrimp (Penaeus monodon) fed on Different Dietary Levels of Fish Meal Protein

“…In the Israeli and Afghani population, the incidence of lactose intolerant was found higher i.e. 82-97% and 83%, respectively (Rahimi et al, 1976). In a similar manner, Southern Indians were more LNP as compared to Northern Indians which are in the closest neighbourhood and are collectively considered as the descendants of Aryans (Asmawi et al, 2006;Tandon et al, 1981;Tomar, 2014).…”