If we may speak in such terms, what was the “original sin” of agribusiness? The short answer: promoting settled agriculture as an (almost) universal cultural trait of our species. While it enhanced humans’ capacity to survive multiple famines, it has led to notable adverse consequences. In modern times, these include obesity, the dominance of cereal grains as the major component of the human diet, deforestation, and soil erosion. Very recently, we have seen biofuels beginning to compete with food crops for agricultural resources. On the local level, health-food stores cash in on people’s anxiety about eating too much junk (manufactured) food. Where is all of this leading—and where is it in the human interest to go instead? In this essay, I will consider a range of problems with agriculture as it exists today—and some possible solutions.
Paradoxes in Nutrition
In my years of medical practice, I was often asked about dietary vitamin supplements. My rule of thumb was that if humans could have benefited from more of a particular vitamin than was supplied from available dietary sources, evolution would have devised some strategy to avoid destroying it or refrain from excreting it so promptly. In other words, I considered most vitamin supplements unnecessary. There was one glaring exception: conclusive evidence was found that administering 0.4 mg of folic acid daily to pregnant women prevents 50 percent of neural tube defects (a common congenital malformation) in their babies. Why was this dietary supplement so spectacularly justified? That amount of folic acid happens to be the amount present in the nuts, roots, and vegetables consumed by our paleolithic (Stone Age) ancestors that is absent from the cereal that now composes a major fraction of civilized human diets. Folic acid supplementation is the necessary penance for our modern-day sin of overreliance on cereals.
The modern dependence on cereals is problematic for several other reasons. Cereals must be milled to release their food value, even if they will undergo subsequent cooking. White flour was not invented to make possible angel-food cake and doughnuts. The original objective was to improve the shelf-life of wheat flour, in part by making it less nutritious to “varmints”—which also made it less nutritious for everybody else. The wheat germ removed during milling contains much of the protein and thiamine (vitamin B1) originally present in wheat. Our thiamine requirement is proportional to the carbohydrate content of our diet, so it was especially appropriate to enrich white flour with thiamine a generation or so ago. Wheat protein is a good source of tryptophan, an essential amino acid that the body can convert to niacin (vitamin B3) if one’s diet is deficient in niacin. Corn happens to be low in both niacin and tryptophan, explaining why southern U.S. diets high in hominy (derived from corn) were associated with pellagra, the disease caused by niacin deficiency.
My wife and I taught medicine in Afghanistan from 1968 to 1970. We noticed that pellagra was prevalent not in people of the lowest socioeconomic stratum—who ate chickpeas, the cheapest staple food on the market—but in the next-to-the-lowest stratum. These people could afford corn and often refused to eat chickpeas because it was beneath them. Chickpeas, also known as garbanzo beans, have much more protein and niacin than corn. It took much educational effort to get these pellagra patients to “eat lower” on the socioeconomic food chain. (The upper classes ate rice, lamb, and vegetables and had excellent nutrition.)
It is good public policy to fortify staple foods with the vitamins likely to be deficient in diets customary in a given region. We have long done this in our country, for example, adding thiamine to flour and vitamin D to milk. (Folic acid enrichment came along much more recently.) Also by diversifying our food choices, as our Paleolithic ancestors did, we can regain the health we have forfeited by eating too “monoculturally.” This works because a larger group of regularly eaten foods is less likely to be deficient in any particular nutrient, especially if few of them are manufactured foods. Eating some chickpeas in addition to corn illustrates the point.
Manufactured trans-fatty acids are another sin of agribusiness. They are unnecessarily created in the manufacture of margarine and other solid vegetable shortenings by partially hydrogenating (adding hydrogen catalytically to) vegetable oil.* Totally saturating some of the vegetable fat with hydrogen and adding it to some of the unmodified oil can solidify the fat without the harm of trans-fatty acids. There are no trans-fats in natural vegetable oil. New York City now prohibits manufactured trans-fats in restaurant food. (The small amounts of natural trans-fats in the meat and milk of ruminant animals is created naturally by their rumen bacteria and may still be served.)
The Need for Epiphanies
Of course, agriculturalists received no specific instruction not to eat from a particular apple tree as Eve legendarily did, but the metaphor does accurately predict that the original sin of agribusiness will haunt mankind more or less indefinitely. No preternatural atonement is likely to intervene, so we will have to depend on numerous individual and collective epiphanies to induce, for example, more consumption of vegetables locally grown and prepared from scratch when convenient. Already, a trend toward more small gardens among householders is encouraging.
Agribusiness interests are beginning to do some secular penance for their original sin. They will do more with an educated public to watch them. The legislators who prescribe the penance will also need watching.
More secular penance: research in replacing annual crops with equivalent perennials is underway. Currently, we grow 80 percent annual crops such as corn and soybeans and only 20 percent perennials such as alfalfa. We can reverse the percentage, but it will take a few decades. Perennial rice already exists, and perennial wheat is under development at the Land Institute in Kansas. This bodes well for reducing soil erosion and conserving fossil fuels and fertilizer. Perennial crops need not be replanted annually, eliminating much mechanical preparation of the fields. Moreover, their widespread roots utilize soil nutrients efficiently, reducing the need for fertilizer.
Meanwhile, agribusiness has learned a bit about salvaging good nutrition from sources formerly wasted. A generation ago, a small amount of whey left over from cheese production was used in making ricotta cheese; the rest (the vast majority) was fed to pigs or even spread on fields as fertilizer, in spite of the fact that whey contains the best protein found in milk. That protein is called “lactalbumen,” and it has all the essential amino acids in the most nutritious proportions for humans. Now, much whey is dried and used in manufactured foods.
If agribusiness is to find “salvation,” it will need further “epiphanies” to discover many similar “paths of righteousness.” Next, let me offer some perspectives from prehistory.
More Paradoxes of Nutrition
An item in Science described a study of survivors of ischemic heart disease with impaired glucose tolerance.** Experimental subjects were assigned either a typical Mediterranean diet of cereal, dairy, meat, monounsaturated oil, vegetables, and fruit or a Paleolithic (“old Stone Age”) diet similar to the above but without the cereal and dairy and with a few root vegetables such as potatoes thrown in. There was a striking improvement in glucose tolerance after twelve weeks in the Paleolithic group compared to the Mediterranean—26 percent achieved normal fasting blood glucose compared to 7 percent
on the Mediterranean diet (rather casually attributed to less lectin from cereal and no casein from milk). Because this population was selected from people already exhibiting heart disease and glucose intolerance, it is highly premature to recommend meat instead of milk for the general public.
I have long thought that Homo sapiens evolved as a hunter-gatherer without enough time to have evolved very much in response to settled agriculture. The ability to digest lactose as adults, for example, is a very recent event in evolutionary terms and seen only among human groups that have kept dairy animals. Even that is not a vast change, involving only the period during one’s life span when lactose can be efficiently digested. Milk has always been food only for mammalian young: even duck-billed platypuses, the most primitive living mammals, have lactose in their milk. So the authors of that study may be justified in thinking that we might be better adapted evolutionarily to a Paleolithic diet than to a more modern one.
Moving from Nutrition to Economics
The socialists among us might argue that accumulated wealth and its extreme social stratification are recent negative developments that depend on settled agriculture. Significant concentrations of wealth may first have become possible in connection with such decidedly non-portable agricultural products as stored grain and domesticated animal herds. Some unintended consequences follow.
Slash-and-burn agriculture arose quickly, likely because of population pressure. Interestingly, the slash-and-burn approach is unstable; anthropologists have observed that in modern times, slash-and-burn agriculturalists revert to hunting and gathering when feasible because it is much less work. Reversion to hunting and gathering occurred on a vast scale in Amazonia after native populations were decimated by European diseases, which they contracted from the Andean Incas well before European exploration of the Amazon began. Recent research shows that, for example, an area the size of France had been cultivated for a millennium or so, the forest growing back shortly before white explorers could have “discovered” it!
Chainsaws and dynamite (for stump removal) are not needed for deforestation. Sustained overuse, even with simple technologies, will do the job. Crops of annual plants erode soil. Even clearing forests for grazing destroys other natural capital services that can reduce flooding and avoid desertification. Pressures such as these stripped Japan of its forests more than three centuries ago. They were restored by a tyrant who is now greatly respected for this accomplishment. In Madagascar, deforestation has persisted for centuries without the benefit of a tyrant to reverse it.
Closer to home, approximately two-thirds of topsoil in heavily cropped areas in North America has been lost. Soil erosion continues, despite the lesson of the “dust bowl” of the 1930s. Very recently, steeply sloping cropland not suitable for corn production has been returned to this use because of the ethanol fad.***
How can we stop soil erosion? The ultimate solutions are reforestation and, wherever possible, switching from annual to perennial food and energy crops.
The Coming Phosphate Crisis
It takes about five times as much acreage to feed a person who eats meat as to feed a vegan. This is because of all the calories an animal consumes during its life, which far exceed the calories available from its carcass. But all modern agriculture, organic or conventional, relies on fertilization. All farmers now face an impending shortage of fertilizer. The phosphorus in chemical fertilizer comes from mined phosphate rock. Worldwide, known reserves will be mined out in, at most, a few centuries. The United States has only enough phosphate deposits for a generation or so at the rate of current usage.
Fertilizer was not needed for crops prior to the advent of civilization and settled agriculture. Previously, animals (including humans) distributed their excrement diffusely, and plants could reuse the nitrogen, phosphorus, potassium, and other elements. Some nitrogen and potassium are lost in the natural recycling of nutrients—the nitrogen to the atmosphere by bacterial action and the potassium by leaching. The nitrogen was replaced by legumes, which have bacteria on their roots that “fix” atmospheric nitrogen in the soil. Additional nitrogen is restored through formation of nitric oxide by lightning discharges. Potassium is replaced by the breakdown of clay as new soil is formed.
Because settled agriculture depletes nitrogen, phosphorus, and potassium from soil much faster than natural processes can replace them, modern fertilization practice has focused on adding back all three bulk chemical elements in the proportions needed by plants. Recent practice is to apply phosphorus more sparingly than that. It is well-retained in soil, but when excess phosphorus does run off, it severely pollutes lakes and rivers, to take one example, contributing to algal blooms. Fortunately, phosphorus can be thoroughly recycled—and it must be. Our former practice of mining it as needed and dumping the waste at sea or in landfills (as sewage sludge) is unsustainable. Future practices must stress recycling. Additional benefits, especially in the form of reduced energy consumption, can be enhanced by keeping producers and users of phosphorus geographically close to one another.
Settled agriculture hastened to focus food production in remote rural locations, isolated from population centers. One promising small-scale remedy for this has been the community garden movement. Community gardens can serve several important purposes. They improve health, reduce energy use by reducing the need for long-distance transport, reduce reliance on chemical fertilizers by recycling human waste (mostly in Asia so far), and demonstrate the improved quality of really fresh vegetables.
Ironically, in some larger cities, rising land prices have led to pressure to convert community gardens for building projects. Fortunately, farmers’ markets similarly provide urban centers with fresh vegetables grown in nearby rural areas. An afterthought: modern construction technology permits gardens on flat roofs, even on very tall buildings. In large cities, such gardens might enjoy minimal pilfering because only the tenants of each building would have access.
Doubling the Benefits
The following case study from China shows how fertilizer supplies can be enhanced, reducing depletion of dwindling natural deposits while also improving public health. Not very long after the Maoist takeover, the government tried to prohibit the use of night soil (human waste) for fertilizer. It did this as part of a campaign to combat parasitic diseases spread by contact with human feces. Rural farmers resisted; they had always used night soil and they knew that their crops flourished with it. A little constructive applied research revealed a middle way: composting night soil (letting it ferment) for at least six weeks before distributing it on the fields. This destroyed the parasites; equally important, it was a practice peasant farmers willingly adopted. (In many areas, farmers had composted night soil for centuries; they just hadn’t been doing so consistently.) In consequence, large areas of China became free of diseases such as schistosomiasis.
We can learn from China’s experience. We already ferment sewage in sewage disposal plants, but only after it has been mixed with industrial waste that includes really bad stuff, such as cadmium from electroplating. To emulate the Chinese success, all we have to do is to separate the industrial and domestic waste (including illegally introduced heavy metals) before it gets to the sewage disposal plant. The resulting sludge will become quality fertilizer. When I was a child, hardware stores in Indianapolis sold green sacks of Milorganite—dried Milwaukee s
ewage sludge—for garden fertilizer. State regulations now forbid crops for human consumption to be fertilized with sewage sludge (though Milorganite and similar products remain on the market for home use).
All of this suggests a way forward to maximize recycling of soon-to-be-scarce phosphorus. First, harmful household and industrial chemicals need to be kept out of sewage streams, especially in large cities. This could perhaps be achieved by regulation of industry and by expanding domestic recycling programs. If not, one day we may need two parallel sewer systems, one for human and food waste and the other for everything else.
Second, studies should explore whether harmful microbes survive current processes by which human waste is made into sludge. It may be that only an additional composting step may be required to make the material safe. If so, this might greatly reduce the cost of phosphorus recycling by permitting sludge to be used with no more restrictions than animal manure for fertilizing human food crops.
Third, we can better recycle manure from farm animals. Recent trends toward large, highly concentrated feedlots and dairy farms—now criticized for the sewage-disposal problems they pose—might actually make it economical to collect animal waste and transport it to farm fields as liquid in pipelines, just as we now transport petroleum.
Fourth, we can explore more radical initiatives. I have done some “back of the envelope” calculations about the quantity of fertilizer that might accrue per year from the excretion of one adult human. It works out to a little more than two fifty-pound sacks of 10-10-10 fertilizer (10 percent each of nitrogen, phosphorus, and potassium). Interestingly, this is about one person’s share of fertilizer for a subsistence garden. Admittedly, some organization and incentives would have to be worked out, but in principle it is a viable plan to use the same phosphorus atoms over and over.
In any truly large-scale effort to recycle phosphorus, some nitrogen will be lost to the atmosphere as gas during fermentation. This must be replaced in order to have a complete fertilizing program. The choices are either by industrial chemical fixation of nitrogen or by cultivating perennial crops alongside legumes that fix nitrogen naturally. (The Land Institute is testing one such combination, pairing perennial wheat with the legume Illinois bundleflower.)
The Challenge We Face
In 1996, the United Nations announced that it would strive to cut the number of hungry people in half worldwide by 2015. Instead of falling, the number of hungry people has increased by 3 percent over the past ten years. The sins of agribusiness loom large in this quandary at the local, national, and global levels. Consider that:
• Fewer and fewer multinational corporations are supplying more and more of our food and transporting it longer and longer distances.
• Crop subsidies, originally intended to help family farms in the developed world, are now mostly paid to big producers.
• Consumption of locally grown foods, even fruits and vegetables, is steadily falling.
Among the needed reforms are:
• revising farm subsidies to accomplish their original intent, keeping small farmers in business;
• eliminating perverse farm subsidies in rich countries that harm farmers in the developing world by artificially lowering prices worldwide;
• reducing or eliminating the growing of biofuels on cropland, which places unnecessary pressure on food supplies, encourages cropping on suboptimal land, and in many cases yields no more energy than was consumed in producing the biofuel;
• replacing, when possible, annual crops for both food and energy with perennials; and
• encouraging consumption of locally sourced fresh food.
Global warming is going to cause heavier rains but fewer of them in many areas. New methods of tilling to promote long retention of soil moisture will have to be perfected and taught to farmers in the affected regions, most notably in sub-Saharan Africa.
Finally, most of us can avoid obesity by getting enough exercise to justify what we eat. In a very real sense, that’s the only penance that can be performed in advance of sinning.
*Care for a technical explanation? The catalyst and heat activate all the carbon-to-carbon double bonds—those not hydrogenated switch from the cis isomer to the more thermodynamically stable, but less healthy, trans isomer.
** S. Lindeberg et al., “A Paleolithic Diet Improves Glucose Tolerance More than a Mediterranean-like Diet in Individuals with Ischemic Heart Disease,” Diabetologia 50 (July 13, 2007): 1795–1807. See also Science 317: 175.
***Never mind that the fuel value of the ethanol produced is roughly equal to the fuel value of the petroleum used in fieldwork and the natural gas used in distilling the concentrated ethanol.
John A. Frantz had a long career as a physician, which included teaching internal medicine as a Peace Corps volunteer.