New York America used to be the tallest country in the world.
From the days of the Founding Fathers right on through the industrial revolution and two world wars, Americans literally towered over other nations. In a land of boundless open spaces and limitless natural abundance, the young nation transformed its increasing wealth into human growth.
But just as it has in so many other arenas, America's predominance in height has faded. Americans reached a height plateau after World War II, gradually falling behind as the rest of the world continued growing taller.
By the time the baby boomers reached adulthood in the 1960s, most northern and western European countries had caught up with and surpassed the United States. Young adults in Japan and other prosperous Asian countries now stand nearly as tall as Americans do.
Even residents of the formerly communist East Germany are taller than Americans today. In Holland, the tallest country in the world, the typical man now measures 6 feet, a good two inches more than his average American counterpart.
Compare that to 1850, when the situation was reversed. Not just the Dutch but all the nations of western Europe stood 2 1/2 inches shorter than their American brethren.
Does it really matter? Does being taller give the Dutch any advantage over say, the Chinese (men 5 feet, 4.9 inches; women 5 feet, 0.8 inches) or the Brazilians (men 5 feet, 6.5 inches; women 5 feet, 3 inches)?
Many economists argue that it does matter, because height is correlated with numerous measures of a population's well-being. Tall people are healthier, wealthier and live longer than short people. Some researchers have even suggested that tall people are more intelligent.
It's not that being tall actually makes you smarter, richer or healthier. It's that the same things that make you tall - a nutritious diet, good prenatal care and a healthy childhood - also benefit you in those other ways.
That makes height a good indicator for economists who are interested in measuring how well a nation provides for its citizens during their prime growing years. With one simple, easily collected statistic, economists can essentially measure how well a society prepares its children for life.
"This is the part of the society that usually eludes economists, because economists are usually thinking about income. And this is the part of the society that doesn't earn an income," said John Komlos, an economic historian at the University of Munich who was born in Hungary, grew up in Chicago, and has spent the last quarter century compiling data on the heights of nations.
For several years now, Komlos and other researchers have been trying to figure out exactly why the United States fell behind. How could the wealthiest country in the world, during the most robust economic expansion in its history, simply stop growing?
Like many human traits, an individual's height is determined by a mix of genes and environment. Some experts put the contribution of genes at 40 percent, some at 70 percent, some even higher. But they all agree that aside from African pygmies and a few similar exceptions, most populations have about the same genetic potential for height.
That leaves environment to determine the differences in height between populations around the world, specifically the environment children experience from the moment of conception through adolescence. Any deficiency along the way, from poor prenatal care to early childhood disease or malnutrition, can prevent a person from reaching his or her full genetic height potential.
Kolmos' latest research paper, published in the June issue of Social Science Quarterly, suggests the blame may lie with America's poor diet and its expensive, inequitable health-care system.
In another recent paper, Komlos also found height inequality between American urbanites and residents of suburbs and rural areas. In Kansas, for example, white males are about as tall as their European peers; it's big cities like New York, where men are about 1.75 inches shorter, that drag America's average down.