Conventional farming and organic farming were the same thing before World War II, with small farms producing most of our foods. In 1900, one farmer fed about 2.5 people. Today, fortunately, one farmer feeds about 100 people.
After World War II, the ammonium nitrate used for munitions became available for fertilizer, and pesticides such as DDT that were used during the war to fight insects in the tropics began to be used in farming. Needless to say, DDT turned out to be a bad idea.
Meanwhile a number of advocates had begun experimental farming using traditional low tech methods in Europe. Principal among these were Sir Albert Howard’s study of Indian farming practices in Bengal and his treatise An Agricultural Testament, which discussed management of compost, soil aeration and pest control using natural enemies.
Meanwhile in Germany, Rudolph Steiner developed the theory of biodynamic agriculture which while a direct ancestor of modern organic farming practices, was shot through with mysticism and rituals such as burying an animal skull in your fields, and the addition of peculiar substances such a s crushed powdered quartz stuffed into the horn of a cow and buried in the field.
As the influence of Rachel Carson’s The Silent Spring grew, there was increased interest in the reduction of harmful pesticides such as DDT in the fields and the concomitant reduction in the use of soluble mineral fertilizers.
Today organic farming can be certified by one of several third party agencies based on standards agreed to by the USDA. What seems to be lacking in this revolution, however, is much study of how different organic foods actually are and whether all this effort is worth it.
Such studies have been done, however, with some surprising results.
A 2009 paper by Dangour, et al conducted a review of 50 years of PubMed articles and identified 162 studies, 55 of satisfactory quality comparing conventionally produced crops with organically produced crops.
For 10 of the 13 nutrient categories analyzed, there were no significant differences between production methods.
There were slight differences in N, P and acidity: conventionally produced crops had a significantly higher nitrogen content and organically produced crops a higher phosphorus content and acidity.
There was no detectable difference in meat from organic and conventional livestock. They concluded that
“There is no evidence of a difference in nutrient quality between organically and conventionally produced foodstuffs. The small differences in nutrient content are biologically plausible and most relate to differences in production methods.”
They did not find strong evidence that organic foods are more nutritious or carry fewer health risks than conventional alternatives, though consumption of organic foods can reduce the risk of pesticide exposure.
This then raises the question of how serious the pesticide residue problem is on conventional and organic foods.
The Dirty Dozen
Each year, the Environmental Working Group publishes a list of the foods with the most pesticide residue, calling them the Dirty Dozen. However, a 2011 peer-reviewed paper by Winter and Katz in the Journal of Toxicology reanalyzed the USDA data used by the EWG, showing that all of the dirty dozen foods had significantly lower pesticide residue than the chronic reference dose (RfD).
This RfD is the amount a person would need to ingest daily for their entire life in order see any effects. The residues in the Dirty Dozen list were for the most part thousands of times lower than that daily reference dose. Only the residue of methamidophos on bell peppers was higher, and it was still 49.5 times lower than the RfD.
And, interestingly, 23% of organic crops were found to have pesticide residues as well, just different ones.
In the article Urban Myths of Organic Farming published in Nature by Trewavas, he points out that “organic pesticides” are actually nastier than those used on conventional farming:
• Copper sulfate causes liver damage in vineyard workers
• Rotenone has been shown to induce Parkinson’s disease symptoms
• Bacillus thuringiensis spores cause fatal lung infections in mice.
So, if organic crops are no more nutritious and conventional crops have no significant pesticide residues, why are we paying a 10-50% premium for them?
Well, one reason might be that they might be locally grown, and thus fresher at the market than those trucked some distance. But this would be true regardless of the farming method used.
In summary, regardless of the hard work and sincerity of organic advocates, there just doesn’t seem to be any reason to pay a premium for organic foods. The extra cost created by being more labor intensive and less productive in the fields is just not justified.
Look for the freshest local fruits and vegetables you can find and eschew the organic premium.