At the start of the Agricultural Revolution our species was so well adapted to its environment that it could hardly be improved upon. Through more than 2 million years of evolution Homo sapiens' body chemistry adapted to the plants, animals and insects among which they lived. Still a part of the food chain - and not necessarily at the top of it - humans that populated the planet 40,000 years ago were biologically successful.
All through their existence humans were just as robust, just as healthy and just as reproductively successful as any species of animal. The Agricultural Revolution that began about 12,000 years ago changed everything. The achievement that was a cultural triumph was a biological disaster. Before the Agricultural Revolution, Homo sapiens could draw nourishment from any of a hundred plants, from scores of small animal species and from hundreds of bird types and their eggs. The relative ease of harvesting plants from a small area instead of wandering for miles to gather them was a pivotal discovery. Raising animals in pens removed the unpredictability and danger of hunting them in the open. Unfortunately, not all plants and animals cooperate for domestication so diversity gave way to convenience. Modern population groups subsist almost entirely on fewer than a dozen types of cereal grains and a handful of animal species. Today's supermarket sells meat from only three animals, cattle, swine and sheep. Chicken and turkey alone represent nearly 100 percent of the fowl that we use for food.
Farmers have to stay put and in doing so they make themselves vulnerable. Permanent as well as seasonal settlements introduce health hazards that small widely-separated bands of hunter-gatherers never have to face: pollution, epidemics and famine.
A settlement, no matter how small, requires drinkable water. When formerly wandering groups stayed in one place their waste began to accumulate and it contaminated their water supply. Instead of being carried off by rain and diluted by large lakes and flowing streams, parasites and other microbes reached high concentrations that inevitably infected the humans who previously were able to avoid them. As villages grew into towns and cities, germs proliferated too and the first epidemics appeared. If a small band of hunter-gatherers encountered a bacterium such as the plague bacillus from a visiting rodent, the entire band might die but the infection would spread no farther. When the same bacterium entered a city, thousands would perish. That number rose to millions during the centuries that followed the rise of kingdoms and empires.
Modern advances have not eliminated epidemics. On the contrary, they have facilitated them. Air travel allowed the SARS virus to spread from Asia to North America within hours. West Nile virus has affected increasing numbers of Americans every year since its introduction from Africa less than a generation ago. Neither SARS nor the West Nile virus would have gotten very far during the Stone Age.
The primitive vocabulary of Stone Age humans probably didn't include the term famine. They likely couldn't imagine a time when food nearly disappeared. In Africa and the Middle East and later in what are now modern Europe and the Americas their generational wisdom led them to food sources even in a prolonged drought. Australian Aborigines have survived quite well in the parched desert-like bush while European explorers, relying on familiar-looking plants and animals, starved there.
Famines only occur when the populace depends on a single crop. Reliance on potatoes in Ireland, rice in Asia and grains in other parts of the world made famine inevitable when disaster struck in the form of blight, drought or flood and the crop that the population depended on vanished.
More subtle than famine, nutritional deficiency marked man's transition from hunting and gathering to farming. In every population group that scientists have studied the agricultural lifestyle brought shortened lifespan, higher infant mortality, smaller stature and chronic anemia.
We continue to squander our evolutionary heritage. In the last 100 years milled flour, refined sugar, harmful fats and salt-laden prepared foods have become the slow, silent killers of the Baby Boomers and their heirs. Barring near-miraculous new breakthroughs in medicine, the present generation of young persons will have a lower life expectancy than their parents while enduring decades of diabetic complications, the aftermath of strokes, the debility of osteoporosis and the pervasive fog of dementia.
It isn't necessary to revert to the Stone Age in order to turn back the major chronic diseases of the First World. A Mediterranean-type diet, high in plant foods, whole grains and fish, low in red meat, dairy products and all forms of sugar will do. Moderately intense physical activity throughout life would nearly eliminate type 2 diabetes, osteoporosis and dementia, as it has done for the aged of Okinawa, who in their tenth decade can reel off the names of their great-grandchildren.
Only 600 generations have passed since the beginning of the Agricultural Revolution. Perhaps we can get back on track during the next 600.
Philip J. Goscienski, M.D. is known as The Stone Age Doc, author of Health Secrets of the Stone Age, Better Life Publishers 2005 and scores of articles that show why the so-called diseases of aging, including osteoporosis, are avoidable with a few lifestyle changes that anyone can make without special potions or programs. Archived articles from his weekly newspaper column, The Stone Age Doc, cover topics that range from asthma to omega-fats and are available at http://www.stoneagedoc.com A Press Room provides author bio and show prep information.
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