Scientists try to explain why Dutch people are so tall

The Netherlands is the land of giants: on average, its women stand almost 1.71 metres (5.6 feet) tall, and its men 1.84 metres.

A popular explanation to height is nutrition – a calorie-stuffed diet rich in meat and dairy products. But that can’t be the whole story, The Guardian reports, citing experts.

Researchers led by Gert Stulp, a specialist in population health at the London School of Hygiene and Tropical Medicine, combed a Dutch database for clues.

Called LifeLines, the record contains exhaustive detail about the lives and health of more than 94,500 people who lived in the northern the Netherlands from 1935 to 1967. In this three-decade snapshot, the people who had the most children were tall men, and women of average height, the team found.

For example, the most fertile men were seven centimetres above the average height. Statistically, they had 0.24 more children on average than the least fertile men, who were about 14 cm below the average height.

Compared to counterparts in other countries where they often tended to have fewer children, taller women also reproduced more in the Netherlands. Many postponed having children until after their studies, but once they forged a successful relationship, often had a large family.

The study did not involve genetic testing, but concluded from the observations that natural selection must have played a part: with time, more and more Dutch started sporting tall genes.

“Natural selection in addition to good environmental conditions may help explain why the Dutch are so tall,” said the study published Wednesday in the Royal Society journal Proceedings B.

“Height is very heritable – taller parents tend to have somewhat taller children than shorter parents,” Stulp said. “Because taller individuals would have more offspring in the next generation who would be taller, the average height in that generation would a bit taller on average than the preceding generation, if all else is equal.”

There seems to be a cultural preference as well.

Stulp pointed to figures showing that, in the United States, shorter women and men of average height have the most reproductive success.

“There is much variation in what men and women want,” he said. “When it comes to choosing a mate, height tends to have (only) a small effect, which is not very surprising given the many other, more important, traits people value in their mate.”