- Human height has changed unevenly through last century, research finds
- Simple height measurement can indicate several things about human health
(CNN)On average, we're taller than our predecessors thanks to better nutrition and health, according to new research released Tuesday .
But those gains vary vastly by country.
"Over the past century adult height has changed substantially and unevenly in the world's countries, according to research published in the journal eLife.
Authors found that people from central and southern Europe, as well as East Asia, grew taller in the last 100 years. Meanwhile there was little gain in height for people from sub-Saharan African and South Asian nations. A few countries experienced decreases in their average adult height after years of gain.
Researchers found that Dutch men, at 182.5 centimeters (about 6 feet), and Latvian women, at 170 centimeters (5 feet 7 inches), are the tallest in the world .
Men from Timor-Leste, at 160 centimeters (5 feet 3 inches), and Guatemalan women, at 149 centimeters (4 feet 11 inches), are considered the shortest.
The Non-Communicable Diseases Risk Factor Collaboration (NCD-RisC), which is a network of health scientists that works closely with the World Health Organization, conducted the height research.
Authors used nearly 1,500 worldwide population-based data, such as publicly available measurement surveys, to estimate height for people from all over the world born between 1896 to 1996.
What happened to the United States?
Meanwhile, Americans aren't quite as tall compared with the rest of the world anymore.
A century ago, American men ranked as the third tallest in the world, standing at 171 centimeters (5 feet 7 inches). Now, they place as the 37th, with an average of 177 centimeters (5 feet 10 inches).
Similarly, American women had ranked as the fourth tallest in the world at 159 centimeters (5 feet 3 inches). Now, they stand as the 42nd tallest in the world with an average of 163.5 centimeters (5 feet 4 inches).
While Americans didn't experience big gains in height, their body mass index "increased a great deal," the report found.
Being tall has its perks
Being tall is associated with better health such as living longer, being less likely to suffer from heart and respiratory diseases, according to research. Also, taller women are less likely to have complications during birth.
On the flip side, authors noted that greater height is associated with certain types of cancers such as colon, breast and ovarian cancers.
There are also social advantages.
Studies indicate that taller people get higher education and better income. One study published earlier this year in the BMJ found that the men with genes that will likely lead them to be tall, have about $4,175 higher annual household income than those who don't.
How height shows inequalities
Height involves genetics, but also is tied to external factors, authors wrote.
For instance, researchers noted that "nutrition and infections during childhood and adolescence are particularly important determinants of height during adulthood."
Simple height measurement can indicate several things.
"Adult height is a link between these early-life experiences and non-communicable diseases, longevity, education and earnings. It can easily be measured in health surveys and can be used to investigate differences across countries ... as well as within-country inequalities," researchers wrote.
South Korean women made the largest gains in height, according to the report.
South Korean women who were born in 1896 were considered the third shortest nation in the world. They measured 142 centimeters tall (4 feet 8 inches). The women born in 1996 are now 162 centimeters (5 feet and 4 inches). That has paralleled the greater rise in economic powers in South Korea and its neighbor China, which also grew in height.
"In contrast to East Asia's impressive gains, the rise in height seems to have stopped early in South Asia and reversed in Africa," researchers wrote. "Prior studies have documented a rise in stunting in children in sub-Saharan Africa which continued to the mid-1990s."
Countries such as Niger, Rwanda and Sierra Leone saw the average heights decrease for people born after the early 1960s.
Countries with tallest men