Technology Advances; Humans Supersize

Next month Cambridge University Press will publish the capstone of this inquiry, “The Changing Body: Health, Nutrition, and Human Development in the Western World Since 1700,” just a few weeks shy of Mr. Fogel’s 85th birthday. The book, which sums up the work of dozens of researchers on one of the most ambitious projects undertaken in economic history, is sure to renew debates over Mr. Fogel’s groundbreaking theories about what some regard as the most significant development in humanity’s long history.

Mr. Fogel and his co-authors, Roderick Floud, Bernard Harris and Sok Chul Hong, maintain that “in most if not quite all parts of the world, the size, shape and longevity of the human body have changed more substantially, and much more rapidly, during the past three centuries than over many previous millennia.” What’s more, they write, this alteration has come about within a time frame that is “minutely short by the standards of Darwinian evolution.”

“The rate of technological and human physiological change in the 20th century has been remarkable,” Mr. Fogel said in an telephone interview from Chicago, where he is the director of the Center for Population Economics at the University of Chicago’s business school. “Beyond that, a synergy between the improved technology and physiology is more than the simple addition of the two.”

This “technophysio evolution,” powered by advances in food production and public health, has so outpaced traditional evolution, the authors argue, that people today stand apart not just from every other species, but from all previous generations of Homo sapiens as well.

 “I don’t know that there is a bigger story in human history than the improvements in health, which include height, weight, disability and longevity,” said Samuel H. Preston, one of the world’s leading demographers and a sociologist at the University of Pennsylvania. Without the 20th century’s improvements in nutrition, sanitation and medicine, only half of the current American population would be alive today, he said.

To take just a few examples, the average adult man in 1850 in America stood about 5 feet 7 inches and weighed about 146 pounds; someone born then was expected to live until about 45. In the 1980s the typical man in his early 30s was about 5 feet 10 inches tall, weighed about 174 pounds and was likely to pass his 75th birthday.

Across the Atlantic, at the time of the French Revolution, a 30-something Frenchman weighed about 110 pounds, compared with 170 pounds now. And in Norway an average 22-year-old man was about 5 ½ inches taller at the end of the 20th century (5 feet 10.7 inches) than in the middle of the 18th century (5 feet 5.2 inches).

Mr. Fogel and his colleagues’ great achievement was to figure out a way to measure some of that gain in body size, Mr. Preston said. Much of the evidence — childhood growth, mortality, adult living standards, labor productivity, food and manufacturing output — was available, but no one had put it all together in this way before. Over the years Mr. Fogel and his colleagues have pored over a monumental amount of raw data to piece together the health records of thousands of people in different countries. When he won the Nobel in economics in 1993, the Swedish committee stated it was “for having renewed research in economic history by applying economic theory and quantitative methods in order to explain economic and institutional change.”

“The Changing Body” is full of statistical tables and graphs that include the heights of girls in Croatia and Germany; the caloric energy derived from potatoes, fish and wine; and the average annual allowance of grains and meat for widows in Middlesex County, Mass., from 1654 to 1799 — a testament to both the staggering accumulation of information and the collaborative nature of the enterprise.