Vuorisalo Timo, Arjamaa Olli, Vasemägi Anti, Taavitsainen Jussi-Pekka, Tourunen Auli, Saloniemi Irma
Department of Biology, University of Turku, Finland.
Perspect Biol Med. 2012;55(2):163-74. doi: 10.1353/pbm.2012.0016.
The main carbohydrate in milk is lactose, which must be hydrolyzed to glucose and galactose before the sugars can be digested. While 65% or more of the total human population are lactose intolerant, in some human populations lactase activity commonly persists into adulthood. Lactose tolerance is exceptionally widespread in Northern European countries such as Sweden and Finland, with tolerance levels of 74% and 82%, respectively. Theoretically, this may result either from a strong local selection pressure for lactose tolerance, or from immigration of lactose tolerant people to Northern Europe. We provide several lines of archaeological and historical evidence suggesting that the high lactose tolerance in North Europeans cannot be explained by selection from in situ milk consumption. First, fresh cow milk has not belonged to the traditional diet of Swedes or Finns until recent times. Second, not enough milk has been available for adult consumption. Cattle herding has been neither widespread nor productive enough in Northern Europe to have provided constant access to fresh milk. We suggest that the high prevalence of lactose tolerance in Finland in particular may be explained by immigration of people representing so-called Corded Ware Culture, an early culture representing agricultural development in Europe.
牛奶中的主要碳水化合物是乳糖，乳糖必须先水解为葡萄糖和半乳糖，这些糖类才能被消化。虽然65%或更多的总人口乳糖不耐受，但在一些人群中，乳糖酶活性通常会持续到成年。乳糖耐受性在瑞典和芬兰等北欧国家尤为普遍，耐受性水平分别为74%和82%。从理论上讲，这可能是由于当地对乳糖耐受性的强烈选择压力，或者是乳糖耐受人群移民到北欧所致。我们提供了几条考古和历史证据，表明北欧人对乳糖的高耐受性无法用就地饮用牛奶的选择来解释。首先，直到近代，新鲜牛奶才成为瑞典人或芬兰人的传统饮食。其次，可供成年人饮用的牛奶不足。在北欧，放牧牛群既不普遍，产量也不足以持续提供新鲜牛奶。我们认为，尤其是芬兰乳糖耐受性的高流行率，可能是由代表所谓绳纹器文化的人群移民造成的，绳纹器文化是代表欧洲农业发展的早期文化。
