America used to be the world’s tallest nation until 2007 when Holland passed us. In 1850 the average American was 2.5 inches taller than your average European. The change has mostly come from opening the floodgates to immigrants in the 1960s. We imported a lot of people shorter than the average American. No doubt better nutrition in other nations, especially Asia, has increased their height. But the biggest reason why America lost its standing as the tallest nation in 2007 is the simple importing of 10s of millions of immigrants over the past 50 years.
I should have said non western European immigrants. Our nation is nothing but immigrants and offspring, but I mean when we changed in the 1960s from primarily western European immigrants to mostly Hispanics from the western hemisphere..