Are Danes really tall? 

You are not imagining it. 

According to data collected by the NCD Risk Factor Collaboration, Danish women born in the year 2000 were in 2019 the 3rd tallest in the world, with a mean height of 169.5cm, less than a centimetre behind their slightly taller counterparts in The Netherlands (170.4cm)  and Montenegro (170cm). 

Danish men also tower over most of their global peers, with those born in the year 2000 in 2019 ranking sixth worldwide with a mean height of 181.9cm, compared to 183.8cm for 19-year-olds in The Netherlands, 183.3cm for those in Montenegro, 182.8 for those in Estonia, 182.5 in Bosnia Herzegovina, and 182.1 in Iceland.  

So is it all down to healthy supplies of smørrebrod? 

According to an analysis of 100 years of height data by Majid Ezzati, a professor at the UK’s Imperial College, using the NCD data, genetics is only a part of the story. 

“People from different countries grow to different heights. This may be partly due to genetics, but most differences in height between countries have other causes,” he writes. “For example, children and adolescents who are malnourished, or who suffer from serious diseases, will generally be shorter as adults.” 

A look at the chart below from Our World in Data shows how closely human height is correlated to how well countries do on the Human Development Index. Indeed, some researchers have proposed using average height as a development indicator. 

Denmark sits right at the top right corner of this chart, showing that as well as being one of the tallest countries in the world, it is also one of the most developed. 

Only a handful of countries where the average male height is over 175cm score less than 0.7 on the human development index. 

It’s also interesting to look at how quickly some of the countries from the former Soviet bloc have caught up with the Nordic countries. 

In 1960, the average Estonian man was just 174cm tall, and the average Serbian man was 175cm tall, well behind the average Dane at 180cm, and behind even the Spanish and Irish.  By 2016, Estonians had already overtaken the Danes and the Serbs were close behind. 

But it’s not all about good nutrition. 

There are countries, such as Japan, Singapore, and Qatar, that score very highly on human development, but still rank only in the middle in terms of height, and also counties such as Italy and Spain, where men remain a good 10cm shorter than the Danes, despite their countries being almost as developed. 

Are Danes tall because of their Viking genes? 

Not Viking exactly, more steppe nomad. 

According to a study published in Nature in 2015, based on the analysis of genomes from 230 West Eurasians who lived between 6,500 BC and 300 BC, the nomads who migrated to Europe from the steppes of Central Asia and Russia had at least two genes correlated with greater height.

They then passed those on to their descendants in northern Europe. 

The farming tribes who migrated to southern Europe about 2,000 years later from what is now Turkey, on the other hand, lacked these genes linked to height. 

The authors conclude that these two waves of migration explain why northern Europeans like the Danes, Estonians and Dutch tend to be taller than their southern European counterparts. 

“These results suggest that the modern South–North gradient in height across Europe is due to both increased steppe ancestry in northern populations, and selection for decreased height in Early Neolithic migrants to southern Europe,” they write.

Kristian Kristiansen, a Danish researcher at Sweden’s Gothenburg University who was one of the authors, told The Local that the gene for tallness had probably evolved to meet the demands of nomadic life on the steppe, just like the nomad cattle-herding peoples of Africa, such as the Maasai, tend to be taller than the continent’s farming peoples, such as the Bantu. 

“There is a specific gene for tallness that originated in the steppe ancestry that came into Europe a little less than 5,000 years ago,” he said.  “These people were nomads, they lived on a very protein-rich healthy diet, they walked a lot and were physically very active, so over time, there was a selection that at some point developed that gene for height.” 

The farmers who came from Anatolia to Southern Europe about 7,000 years ago, meanwhile would not have had a good enough diet to sustain such stature. 

“Their diet would have been much more based on grain and bread, with fewer meat products, so their diet was not quite as healthy as the pastoral peoples.” 

But that only explains why northern Europeans are taller, surely. 

Correct.

Part of the variation between northern European countries can then be explained by the extent to which the steppe nomad genes are mixed with those of the Anatolian and other migrant groups who have come to Europe, meaning the peoples on the northern periphery of Europe — Scandinavia, the Baltic and The Netherlands — tend to be taller than say, Germans or French. 

More recent immigration is also a factor. Countries that have had high levels of immigration over the last 50 years have tended to drop behind in terms of average height. 

The average Swedish man, for instance, shrunk from 180cm in 1980 to 179.74cm in 1996, a period when the average Danish man grew 181.1 to 181.39, perhaps due to Sweden’s higher labour migration from southern Europe in the 1980s, and the start of immigration from the Middle East. 

A paper published in 2015 in the Proceedings of the Royal Society suggested that part of the reason why the Dutch (and also perhaps the Danes) have in recent decades outpaced their European neighbours might also have something to do with natural selection, with the researchers finding that taller men tend to have more children, indicating that Dutch women are more likely to chose tall mates (and perhaps visa versa).