The first people to drink milk regularly were early farmers and pastoralists in western Europe — some of the first humans to live with domesticated animals, including cows. Today, drinking milk is common practice in northern Europe, North America, and a patchwork of other places. Milk contains a type of sugar called lactose, which is distinct from the sugars found in fruit and other sweet foods.
But after we are weaned in early childhood, for many people this stops. Without lactase, we cannot properly digest the lactose in milk. As a result, if an adult drinks a lot of milk they may experience flatulence, painful cramps and even diarrhoea. So the first Europeans who drank milk probably farted a lot as a result. But then evolution kicked in: some people began to keep their lactase enzymes active into adulthood. It is the result of mutations in a section of DNA that controls the activity of the lactase gene.
The lactase persistence trait was favoured by evolution and today it is extremely common in some populations. The same is true in a few populations in Africa and the Middle East. But there are also many populations where lactase persistence is much rarer: many Africans do not have the trait and it is uncommon in Asia and South America. A woman purchases soy milk in Hong Kong. Dairy can make many people feel sick in Asia, where the lactase persistence trait is uncommon Credit: Getty.
The obvious answer is that drinking milk gave people a new source of nutrients, reducing the risk of starvation. People who are lactase-non-persistent can still eat a certain amount of lactose without ill effects, so drinking a small amount of milk is fine. There is also the option of processing milk into butter, yoghurt, cream or cheese — all of which reduce the amount of lactose. Read more about parmigiano, a cheese with so little lactose it can be eaten by the lactose-intolerant.
Hard cheeses like parmigiano-reggiano can have little to no lactose Credit: Getty. Was this information helpful? Please select your state or territory We need to confirm your location to show you the correct content, products and pricing. Change your state or territory If you change location, we'll reset your quote and refresh the page to show you the content, products and pricing relevant to your location.
The benefits of dairy. You're in WA. Type your search query. Helpful articles 4 signs you should update your health cover Health insurance, tax and June 30 3 ways to keep a positive outlook. Cover for Find a provider. To cope with their lactose intolerance, early Britons may have imbibed small amounts of milk at a time or, in a more plausible scenario, processed the drink to reduce its lactose content. Dairy fats and milk residue discovered in Neolithic pottery across the European continent support this theory, offering evidence of heating and other forms of milk product processing.
Milk also provides a calorie- and protein-rich food source, comes in a relatively constant supply compared to the boom-and-bust of seasonal crops, and would have been less contaminated than water supplies. Evidence from other studies suggest dairying was present in south-eastern Europe soon after the arrival of farming, while milk proteins found in ceramic vessels provide evidence for dairying in present-day Romania and Hungary some 7,, years ago.
Traces of fats also point to dairying at the onset of farming in England some 6, years ago. But it is most likely that milk was first fermented to make yoghurt, butter and cheese, and not drunk fresh. The Romans used goat and sheep milk to produce cheese, and cattle as a draught animal. However, Germanic and Celtic people practiced cattle dairying and drank fresh milk in significant amounts. The current distribution of lactase persistence would seem to suggest an origin in Northwest Europe — especially Ireland and Scandanivia — since it is found at its highest frequency there today.
However, the latest study suggests otherwise. Dairy farmers carrying this gene variant probably originated in central Europe and underwent more widespread and rapid population growth than non-dairying groups. The spread of fresh milk drinking from the Balkans across Europe also explains why most European lactase-persistent people carry the same version of the gene; it surfed on a wave of population expansion that followed the rapid co-evolution of milk tolerance and dairy farming.
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