Average Height in Iran (Men & Women)

Average height in Iran: the headline figures

Iranian adults born in 1996 average 173.6 cm (5′8″) for men and 159.7 cm (5′3″) for women, according to the NCD Risk Factor Collaboration (NCD-RisC). Those are the figures used on this page and in the site's comparison tools.

On their own, those numbers put Iran in the upper-middle of the world. Iranian men rank around 68th of 200 countries and women around 88th. What makes Iran stand out is how it got there. In the NCD-RisC study of a century of human height, Iranian men had the largest height gain of any male population on Earth, 16.5 cm between those born in 1896 and those born in 1996.

The largest male height gain in the world

The NCD-RisC paper, published in eLife in 2016, reanalyzed 1,472 population-based studies with measured heights for more than 18.6 million people. Its headline finding was that the biggest gains in adult height over the 20th century didn't happen in Europe, where the rise in heights had been studied most. They happened in South Korean women, who gained 20.2 cm, and Iranian men, who gained 16.5 cm.

The estimate comes with an uncertainty range. The study's 95 percent credible interval for the Iranian male gain runs from 13.3 cm to 19.7 cm. Even at the low end, that's a larger gain than most European countries managed. The authors note that South Korean and Japanese men and women, and Iranian men, gained more than European men, and they argue that some of the most important changes in height happened in populations that earlier research had overlooked.

Among men, the countries with the next-largest gains in the site's NCD-RisC data are Greenland (15.4 cm), South Korea (15.1 cm), Greece (14.8 cm) and Japan (14.6 cm). Neighboring Turkey, by comparison, gained 13.9 cm.

A century of change, decade by decade

Three phases stand out:

1. Rapid early growth. Men born in 1926 were already 7.3 cm taller than those born 30 years earlier, and women 4.1 cm taller.
2. Continued gains through mid-century. Another 5 cm for men born by 1956, and 3.2 cm more by 1976.
3. Slowing at the end. Between the 1976 and 1996 cohorts, men gained only 1 cm. In the year-by-year NCD-RisC series published by Our World in Data, the 1996 cohort is still the tallest, so Iranian heights hadn't started to fall, but the climb had flattened.

Unlike in many African countries in the same dataset, where heights reversed for people born after the 1960s and 1970s, Iran's averages kept rising through the whole century.

Women gained less, and the gap widened

Iranian women's gains were large by world standards, 11.2 cm, but well short of the men's. As a result, the height difference between Iranian men and women widened from 8.6 cm in the 1896 cohort to 13.9 cm in the 1996 cohort. In the 1896 cohort, Iranian women ranked around 159th of 200, higher than the men's 181st. By 1996 the order had flipped: women ranked around 88th and men around 68th.

The NCD-RisC study reports these trends but doesn't attribute the difference to a specific cause in Iran. Our World in Data notes that differences in height between populations and generations reflect nutrition and health during pregnancy, childhood and adolescence, so the pattern suggests that improvements in those conditions reached boys and girls to different degrees, or affected their growth differently.

Iran alongside the East Asian height boom

The NCD-RisC authors group Iranian men with the populations of Japan and South Korea as the century's biggest gainers, and the numbers show why. All three started the 20th century among the shorter populations in the world and finished it close together.

A few things stand out in this comparison:

• Iran was ahead early. By the 1926 cohort, Iranian men had already caught up with South Korean men and passed Japanese men. Japan's steepest rise came later, between the 1926 and 1956 cohorts.
• The 1956 cohorts were almost identical. Iranian, South Korean and Japanese men born in 1956 all averaged about 169.3 to 169.4 cm in the NCD-RisC estimates.
• The paths split afterwards. South Korean men kept growing to 174.9 cm, Iranian men to 173.6 cm, while Japanese men leveled off and slipped slightly to 170.8 cm. The NCD-RisC paper notes that Japan's impressive rise in height stopped for people born after the early 1960s, while in South Korea it continued into the cohorts born in the 1980s.

For women the picture is different. South Korean women gained 20.1 cm in the site data and Japanese women 16 cm, while Iranian women gained 11.2 cm. Iran's place among the century's top gainers rests on its men.

How Iran compares with the tallest countries

Even after the largest male gain in the world, Iranian men born in 1996 are 8.9 cm shorter than Dutch men (182.5 cm), the tallest population in the NCD-RisC data. But the gap has shrunk. A century earlier, Dutch men born in 1896 were 12.3 cm taller than Iranian men. Against American men, the change is more striking. In the 1896 cohort, American men (171.1 cm) were 14 cm taller than Iranian men. By the 1996 cohort the gap was 3.5 cm.

What the older historical record says

Iran's history can also be read through the Clio-Infra decade-by-decade reconstructions by Joerg Baten and Matthias Blum, shown on Our World in Data. They rely on different historical records from NCD-RisC and start from a different baseline: men at about 165 to 168 cm in the second half of the 19th century, around 168 to 169 cm for the 1940s and 1950s birth decades, and about 172.4 cm for men born in the 1980s.

The two series broadly agree on where Iranian men ended up, at roughly 171 to 174 cm. They disagree on the starting point. Baten and Blum have 19th-century Iranian men several centimeters taller than NCD-RisC's 1896 estimate of 157.1 cm. That means the true size of the century-long gain depends partly on how the earliest cohorts are estimated. Early data are sparse in most countries, which is one reason NCD-RisC reports a credible interval rather than a single certain value.

Iran's own height data

NCD-RisC's estimates are built from measured surveys, and Iranian researchers were well represented in the collaboration, with contributors from Tehran University of Medical Sciences, Shahid Beheshti University of Medical Sciences, the Isfahan Cardiovascular Research Center and Iran's Non-Communicable Diseases Research Center, among others.

One widely cited national analysis is a 2008 study by A. A. Haghdoost, A. Mirzazadeh and S. Alikhani in the Iranian Journal of Public Health, titled "Secular Trend of Height Variations in Iranian Population Born between 1940 and 1984." According to the summary in Wikipedia's compilation of national height surveys, it covered 89,532 measured adults aged 21 and over and reported averages of 170.3 cm for men (standard deviation 8.05 cm) and 157.2 cm for women (standard deviation 7.22 cm), with data from 2005.

Those averages are lower than the NCD-RisC 1996 figures because they include adults born as early as 1940. A sample spanning several generations will always come out shorter than the youngest cohort in a country where heights have been rising. That's why national survey averages and birth-cohort estimates shouldn't be compared directly.

Iran compared with its neighbors

The last column shows how far Iran came. A century ago, Iranian men were shorter than men in every neighboring country listed, 8.6 cm shorter than Pakistani men and 4 cm shorter than Afghan men. By the 1996 cohort they were taller than all of them except Turkish men, and they finished 6.7 cm ahead of Pakistan and 8.3 cm ahead of Afghanistan.

Pakistan's men gained only 1.2 cm over the century in the same data, which matches the NCD-RisC finding that height gains stalled early in South Asia. Iran's trajectory looks much more like those of East Asian countries.

Iranian height in everyday terms

The typical young Iranian man today is about 5′8″ and the typical young woman just over 5′3″. That's roughly the same as men in Turkey and a few centimeters shorter than men in much of southern Europe. For a sense of what that looks like, the 173 cm page shows the conversion and comparisons for the male average, and the height percentile calculator shows where any individual height falls. You can also put two people side by side in the height comparison tool.

Why Iran's height story matters

Height is often used as a measure of a population's "biological standard of living," a term Our World in Data uses because heights record how well children were fed and how healthy they were while growing. Iran's record shows how quickly that can change. Within three or four generations, Iranian men went from among the shortest in the world to above the global middle. The NCD-RisC data don't by themselves explain why. But a change this large within a few generations fits Our World in Data's point that differences between generations mainly reflect nutrition and health, not genes. For a full list of countries on the same basis, see the average height by country hub.