Korean height gap

This week the Wall Street Journal did a pretty thorough review of the North – South Korean “height gap” after John McCain mentioned it in a presidential debate.  Here is a hefty quote from the post (well worth reading here):

…Several checked and (here, here, and here) found studies supporting his claim of a height gap, though the gap’s size depends on which South Koreans and North Koreans you’re measuring. The researchers behind these studies told me that McCain’s statement is true of younger Koreans, but not of adults. (A McCain campaign spokesman didn’t respond to my request for the source of the claim.)

One study of North Korean refugees compared to South Koreans of the same age found that South Korean young men were 2.3 inches taller than their North Korean counterparts, while the gap among young women was 2.6 inches. Meanwhile, among non-refugee boys and girls living in both countries between the ages of one and a half and six and a half, a separate study found that the height gap was around three inches (varying slightly by age and gender); between six and a half and seven and a half, the height gap was 4.9 inches for girls and five inches for boys.

The height gap is so age-dependent for two reasons, researchers told me: People of different ages experience peak growth at different times, and at different times the discrepancies between the two Koreas in nutrition, health and overall well-being may differ. Also, adults who were undernourished as children may catch up slightly later.

“Adults were raised 20 to 50 years ago — thus, you proxy the environmental impact in the past, so it does not really make sense comparing different time periods,” Daniel Schwekendiek, author of the study of child heights, said.

Schwekendiek, an economist at Germany’s University of Tuebingen, was a postdoc student of Sunyoung Pak, a biological anthropologist at Seoul National University who conducted the refugee study. Pak said it’s unclear whether refugees are a representative sample of the North Korean population, though she did point out that the older people she studied, born in the 1930s, were taller than their southern-born counterparts, suggesting that there has been a growing height gap, as North Korean height growth stagnated. (People, like other mammals, tend to be heavier and taller at greater latitudes, Pak said.)

Schwekendiek’s samples were randomly selected — in North Korea, by the United Nations in 10 of 12 provinces, to investigate malnutrition, and in wealthier, healthier South Korea, by the Korean Research Institute of Standards and Sciences, on behalf of industries that wanted to produce goods that fit children.

Both researchers said height is a useful measure of well-being because North Koreans and South Koreans share genetic ancestry, and also because height numbers are more reliable and objective than economic stats coming out of Pyongyang. “As height and weight are measured physically, this leaves less room for political manipulation compared to conventional health and human welfare indicators,” Schwekendiek said.

Wall Street Journal
The Numbers Guy

The Korean Height Gap


Comments are closed.