Ancient Europeans farmed dairy-but couldn't digest milk.

Giant study of ancient pottery and DNA challenges common evolutionary explanation for lactase persistence.

[Lactose intolerance: past and present. Part 1]. / A laktózintoleranciáról: Múlt és jelen - I. rész.

Lactose intolerance is the most prevalent intestinal malabsorption disorder. After presentation of its history, the author describes the emergence of lactose intolerance during the evolution of species, and the biochemistry of lactose as well as features of human and bacterial lactase enzymes are then described. The unequal distribution of lactose intolerance in different continents and population is discussed, followed by presentation of past and present prevalence data in Hungary. Adult-type hypolactasia is caused by a polymorphism of the MCM6 gene located upstream from the lactase gene on the long arm of the chromosome 2. It can be determined with the polymerase chain reaction. The intestinal symptoms of lactose intolerance are well known, but its extra-intestinal manifestations are less recognised. Invasive diagnostic methods (determination of lactase activity from small intestinal biopsies, lactose tolerance test), are accurate, but have been replaced by the non-invasive methods; their gold standard is the H2 breath test. Genetic testing is being used more and more frequently in Hungary too, and, presumably, the methane breath test will be also available in the near future. Lactose intolerance can be accompanied by inflammatory bowel diseases, coeliac disease and irritable bowel syndrome; it could be established whether this association is causal or not in order to start a correct diet and therapy.

The Interrelationships between Lactose Intolerance and the Modern Dairy Industry: Global Perspectives in Evolutional and Historical Backgrounds.

Humans learned to exploit ruminants as a source of milk about 10,000 years ago. Since then, the use of domesticated ruminants as a source of milk and dairy products has expanded until today when the dairy industry has become one of the largest sectors in the modern food industry, including the spread at the present time to countries such as China and Japan. This review analyzes the reasons for this expansion and flourishing. As reviewed in detail, milk has numerous nutritional advantages, most important being almost an irreplaceable source of dietary calcium, hence justifying the effort required to increase its consumption. On the other hand, widespread lactose intolerance among the adult population is a considerable drawback to dairy-based foods consumption. Over the centuries, three factors allowed humans to overcome limitations imposed by lactose intolerance: (i) mutations, which occurred in particular populations, most notably in the north European Celtic societies and African nomads, in which carriers of the lactose intolerance gene converted from being lactose intolerant to lactose tolerant; (ii) the ability to develop low-lactose products such as cheese and yogurt; and (iii) colon microbiome adaptation, which allow lactose intolerant individuals to overcome its intolerance. However, in a few examples in the last decade, modern dairy products, such as the popular and widespread bio-cultured yogurts, were suspected to be unsuitable for lactose intolerant peoples. In addition, the use of lactose and milk-derived products containing lactose in non-dairy products has become widespread. For these reasons, it is concluded that it might be important and helpful to label food that may contain lactose because such information will allow lactose intolerant groups to control lactose intake within the physiological limitations of ~12 g per a single meal.

Ancient DNA analysis reveals high frequency of European lactase persistence allele (T-13910) in medieval central europe.

Ruminant milk and dairy products are important food resources in many European, African, and Middle Eastern societies. These regions are also associated with derived genetic variants for lactase persistence. In mammals, lactase, the enzyme that hydrolyzes the milk sugar lactose, is normally down-regulated after weaning, but at least five human populations around the world have independently evolved mutations regulating the expression of the lactase-phlorizin-hydrolase gene. These mutations result in a dominant lactase persistence phenotype and continued lactase tolerance in adulthood. A single nucleotide polymorphism (SNP) at C/T-13910 is responsible for most lactase persistence in European populations, but when and where the T-13910 polymorphism originated and the evolutionary processes by which it rose to high frequency in Europe have been the subject of strong debate. A history of dairying is presumed to be a prerequisite, but archaeological evidence is lacking. In this study, DNA was extracted from the dentine of 36 individuals excavated at a medieval cemetery in Dalheim, Germany. Eighteen individuals were successfully genotyped for the C/T-13910 SNP by molecular cloning and sequencing, of which 13 (72%) exhibited a European lactase persistence genotype: 44% CT, 28% TT. Previous ancient DNA-based studies found that lactase persistence genotypes fall below detection levels in most regions of Neolithic Europe. Our research shows that by AD 1200, lactase persistence frequency had risen to over 70% in this community in western Central Europe. Given that lactase persistence genotype frequency in present-day Germany and Austria is estimated at 71-80%, our results suggest that genetic lactase persistence likely reached modern levels before the historic population declines associated with the Black Death, thus excluding plague-associated evolutionary forces in the rise of lactase persistence in this region. This new evidence sheds light on the dynamic evolutionary history of the European lactase persistence trait and its global cultural implications.

Earliest evidence for cheese making in the sixth millennium BC in northern Europe.

The introduction of dairying was a critical step in early agriculture, with milk products being rapidly adopted as a major component of the diets of prehistoric farmers and pottery-using late hunter-gatherers. The processing of milk, particularly the production of cheese, would have been a critical development because it not only allowed the preservation of milk products in a non-perishable and transportable form, but also it made milk a more digestible commodity for early prehistoric farmers. The finding of abundant milk residues in pottery vessels from seventh millennium sites from north-western Anatolia provided the earliest evidence of milk processing, although the exact practice could not be explicitly defined. Notably, the discovery of potsherds pierced with small holes appear at early Neolithic sites in temperate Europe in the sixth millennium BC and have been interpreted typologically as 'cheese-strainers', although a direct association with milk processing has not yet been demonstrated. Organic residues preserved in pottery vessels have provided direct evidence for early milk use in the Neolithic period in the Near East and south-eastern Europe, north Africa, Denmark and the British Isles, based on the δ(13)C and Δ(13)C values of the major fatty acids in milk. Here we apply the same approach to investigate the function of sieves/strainer vessels, providing direct chemical evidence for their use in milk processing. The presence of abundant milk fat in these specialized vessels, comparable in form to modern cheese strainers, provides compelling evidence for the vessels having being used to separate fat-rich milk curds from the lactose-containing whey. This new evidence emphasizes the importance of pottery vessels in processing dairy products, particularly in the manufacture of reduced-lactose milk products among lactose-intolerant prehistoric farming communities.

Comparison of lactase persistence polymorphism in ancient and present-day Hungarian populations.

The prevalence of adult-type hypolactasia varies ethnically and geographically among populations. A C/T-13910 single nucleotide polymorphism (SNP) upstream of the lactase gene is known to be associated with lactase non-persistence in Europeans. The aim of this study was to determine the prevalence of lactase persistent and non-persistent genotypes in current Hungarian-speaking populations and in ancient bone samples of classical conquerors and commoners from the 10th-11th centuries from the Carpathian basin; 181 present-day Hungarian, 65 present-day Sekler, and 23 ancient samples were successfully genotyped for the C/T-13910 SNP by the dCAPS PCR-RFLP method. Additional mitochondrial DNA testing was also carried out. In ancient Hungarians, the T-13910 allele was present only in 11% of the population, and exclusively in commoners of European mitochondrial haplogroups who may have been of pre-Hungarian indigenous ancestry. This is despite animal domestication and dairy products having been introduced into the Carpathian basin early in the Neolithic Age. This anomaly may be explained by the Hungarian use of fermented milk products, their greater consumption of ruminant meat than milk, cultural differences, or by their having other lactase-regulating genetic polymorphisms than C/T-13910. The low prevalence of lactase persistence provides additional information on the Asian origin of Hungarians. Present-day Hungarians have been assimilated with the surrounding European populations, since they do not differ significantly from the neighboring populations in their possession of mtDNA and C/T-13910 variants.

Darwin's illness: a final diagnosis.

We have re-examined many of the abundant publications on the illness that afflicted Charles Darwin during most of his life, including some of the 416 health-related letters in his correspondence, as well as his autobiographical writings. We have concluded that he suffered from Crohn's disease, located mainly in his upper small intestine. This explains his upper abdominal pain, his flatulence and vomiting, as well as his articular and neurological symptoms, his 'extreme fatigue', low fever and especially the chronic, relapsing course of his illness that evolved in bouts, did not affect his life expectancy and decreased with old age, and also the time of life at which it started. It apparently does not explain, however, many of his cutaneous symptoms. We do not support other diagnoses such as Chagas' disease, lactose intolerance or the many psychiatric conditions that have been postulated.

Darwin's illness revealed.

After returning from the Beagle in 1836, Charles Darwin suffered for over 40 years from long bouts of vomiting, gut pain, headaches, severe tiredness, skin problems, and depression. Twenty doctors failed to treat him. Many books and papers have explained Darwin's mystery illness as organic or psychosomatic, including arsenic poisoning, Chagas' disease, multiple allergy, hypochondria, or bereavement syndrome. None stand up to full scrutiny. His medical history shows he had an organic problem, exacerbated by depression. Here we show that all Darwin's symptoms match systemic lactose intolerance. Vomiting and gut problems showed up two to three hours after a meal, the time it takes for lactose to reach the large intestine. His family history shows a major inherited component, as with genetically predisposed hypolactasia. Darwin only got better when, by chance, he stopped taking milk and cream. Darwin's illness highlights something else he missed--the importance of lactose in mammalian and human evolution.

Intolerância à lactose: uma breve revisão para o cuidado nutricional / Lactose intolerance: a brief review for the nutritional care

A intolerância à lactose é uma inabilidade para digerir completamente a lactose, o açúcar predominante do leite. A lactose é um dissacarídeo e sua absorção requer hidrólise prévia no intestino delgado por uma b-galactosidase da borda em escova, comumente chamada lactase. A deficiência de lactase conduz à má-digestão da lactose e à conseqüente intolerância. A lactose não digerida, conforme passa pelo cólon, é fermentada por bactérias colônicas, havendo produção de ácidos orgânicos de cadeia curta e gases. Isto resulta em cólicas, flatulência, dor e diarréia osmótica. Existem dois tipos de deficiência de lactase. A deficiência de lactase do tipo primário é uma condição permanente. A forma congênita de deficiência de lactase é muito rara, enquanto a não persistência de lactase do tipo adulto é muito comum e afeta cerca de ¾ da população mundial. A deficiência de lactose secundária é, usualmente, condição temporária causada por dano à mucosa intestinal. Iogurte e outros produtos fermentados, bem como leites hidrolizados, amenizam os sintomas dos intolerantes. Da mesma forma, ingerir pequenas quantidades de leite a cada vez, ingerir leite juntamente com as refeições, usar preferencialmente leite integral e acrescentar chocolate ao leite podem aumentar a tolerância à lactose. Por outro lado, fatores psicológicos devem ser considerados no que diz respeito à intolerância à lactose, já que é sabido que as funções cerebrais exercem forte influência sobre a percepção de sintomas. Este trabalho revisa informações fundamentais sobre má digestão da lactose e intolerância à lactose e discute as possibilidades no tratamento dos intolerantes