Fogel thinks the explanation for this lies in fetal development. Babies with low birth weights tend to be smaller and more prone to illness as adults, he says.
David Barker, a professor of epidemiology at England's University of Southampton, has collaborated on several studies of populations throughout the world.
His research has linked low birth weight to coronary heart disease, chronic renal failure, diabetes, hypertension, and stroke.
"The embryo is very sensitive to the nutrients it's bathed in," Barker said.
He explains that the number of cells your body makes for vital organs is already determined by the time you are born. Stunted growth can have health repercussions throughout a baby's life, he says.
"We've spent the past 20 years of medical research looking at the way the heart is damaged by behaviors of people in their middle livesby what they eat, and how much exercise they take, and if they smoke," Barker said.
"It turns out that isn't the key thing. The key thing is how your heart was made in the first place."
Centuries ago it may have been difficult for pregnant women and their children to get proper nourishment, probably leading to smallerand therefore shorter-livedadults, Fogel says.
Fogel has raised eyebrows by demonstrating how malnourished and sick the ancestors of modern Westerners were in the Old World.
He has pointed out that the quantity and quality of food available to ordinary French and English families from 1700 to 1850 was meager.
In France the daily caloric supply was less than half what it is today. And about 20 percent of England's population in 1790 was so malnourished that they would not have had the energy to do more than walk slowly, Fogel says.
Even in North America, which was comparatively "awash in calories," according to Fogel, people were chronically malnourished, thanks in part to the high rate of infectious diseases.
"Every disease causes a loss of nutrients; it diverts energy from growth," he said.
The woes of earlier Westerners could have implications for how we attempt to thwart chronic disease today, Fogel and his colleagues say.
Barker agrees, arguing that the best thing we can do to prevent chronic disease is look after the health of mothers and their babies in the first two years of life.
"I think that's a bit of a stretch," said Lawrence Appel, a professor of medicine and epidemiology at Johns Hopkins University in Baltimore, Maryland.
Appel says it would be a mistake to ignore the importance of lifestyle influences like diet and exercise throughout a person's life span.
He describes populations in largely primitive societies that aren't exposed to the high levels of salt and fat found in Western diets.
"These populations have a low incidence of hypertension, low incidence of heart disease," he said.
"We don't know much about their [embryonic and fetal] environment. But I would suspect it's not as beneficial [as that of modern Westerners].
"Those are settings where nutrition problems are likely to be prevalent. And despite that, they have a low incidence of disease."
But, Fogel says, it makes sense to think that poorly developed organs may break down earlier than well-developed ones.
Today he is continuing his studies of humans' changing lives and wonders about "human potential."
The Western life expectancy has increased 2.5 years per decade since 1845, and Fogel expects it will continue to do so this century.
As for what heights Westerners might literally reach, "We don't know how tall people can get," he said.
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