Milk may have fuelled a growth spurt in ancient Europeans

An analysis of ancient human skeletons found that increases in size and weight in some regions were consistent with increased lactose tolerance

To Luke Taylor

People in northern and central Europe increased in size between 7,000 and 4,000 years ago, while people elsewhere remained the same height or became smaller.

The growth in some Europeans is likely due to the early evolution of lactose tolerance, researchers say.

The ability to produce the enzyme lactase into adulthood and digest milk is thought to have played an important role in ancient human health and evolution.

Studies suggest that those who were able to consume milk without health complications were able to overcome acute famine, and that lactase persistence spread through natural selection.

To measure the impact of lactose tolerance on human size, Jay Stock and his colleagues at Western University in Ontario, Canada, conducted research in seven regions: the Levant, Southern Europe, Central Europe, and Northern Europe. We collated data on 3507 skeletons from 366 archaeological sites. Nile Basin, South Asia, China – 30,000 years ago.

The researchers used skeletal measurements to estimate the specimen’s height, and the size of its weight-bearing joints to estimate its weight.

They found that the global average height of men and women decreased from 30,000 years ago and reached a minimum between 8,000 and 6,000 years ago. However, height increased between 7,000 and 4,000 years ago in central Europe, and between 8,000 and 2,000 years ago in northern Europe. A similar trend was observed for body weight.

The earliest evidence of dairy production is in western Asia about 9,000 years ago, from where it spread around the world, reaching central Europe at least 7,400 years ago.

The authors theorize that the exceptional growth is a result of Europeans becoming lactose tolerant and getting more nutrition from cow’s milk. , consuming only fermented dairy products low in lactose, such as yogurt and cheese.

Although the data cannot prove that lactase persistence is responsible, the researchers argue that it is a plausible explanation. consistent with what we see in the persistence of lactase, which is an important component of the diet as it provides a very energy and nutrient-rich food source,” Stock said. say.

However, the study found that people in the UK actually got smaller around the same time, even though they drank milk earlier.

“The authors did a pretty good job of stature, estimating weight, and how it changed over time. I don’t see any systematic numerical analysis to suggest anything more,” says Mark Thomas of University College London.

Previous research suggested that reliance on a single crop resulted in low nutritional value, so that humans became smaller when they abandoned hunter-gatherer lifestyles and cultivated crops.

But new research finds strong evidence that people are getting smaller before they transition to farming, suggesting there are other causes for the loss of height, says Thomas.