The dawn of agriculture around the world was accompanied by a surprising trend. From China to South America and everywhere in between, people in farming cultures became shorter and less healthy than their hunter-gathering ancestors.
Amanda Mummert, an anthropology graduate student at Emory University, led a first of its kind review of health and height statistics from the days when agriculture sprouted around the world.
â€œMany people have this image of the rise of agriculture and the dawn of modern civilization, and they just assume that a more stable food source makes you healthier,â€ Mummert said in an Emory press release.
â€œBut early agriculturalists experienced nutritional deficiencies and had a harder time adapting to stress, probably because they became dependent on particular food crops, rather than having a more significantly diverse diet,â€ Mummert said.
â€œCulturally, weâ€™re agricultural chauvinists. We tend to think that producing food is always beneficial, but the picture is much more complex than that,â€ says Emory anthropologist George Armelagos, professor of anthropology and co-author of the study.
Starting around 10,000 years ago, and continuing to relatively recently, no matter where and what crop, the pattern was the same. Agriculture led to shorter, less healthy people.
The spread of disease in concentrated settlements, as well as transmission of diseases from animals may have also played a part.
Gradually the trend reversed, especially after the dawn of mechanized agriculture in the developed world about 75 years ago, noted the authors.
â€œThis broad and consistent pattern holds up when you look at standardized studies of whole skeletons in populations,â€ Mummert said.
Mummert reviewed literature studying factors like adult height, dental cavities and abscesses, bone density, healed fractures, and other indicators of health from populations around the world as they started farming. The populations came from far-flung areas of the globe, including China, Southeast Asia, North and South America, and Europe.
â€œBones are constantly remodeling themselves,â€ Mummert said. â€œSkeletons donâ€™t necessarily tell you what people died of, but they can almost always give you a glimpse into their ability to adapt and survive.â€
â€œHumans paid a heavy biological cost for agriculture, especially when it came to the variety of nutrients. Even now, about 60 percent of our calories come from corn, rice and wheat,â€ said Armelagos.
The idea that agriculture led to a decline in health was pioneered by Armelos and M. N. Cohen back in 1984 in the book Paleoanthropology at the Origins of Agriculture. Though it was controversial at the time, the idea is now widely accepted.
This new study shows how widespread the link between agriculture and declining health was, and gathers into one place the numbers to back-up the assertion.