Remember the large-scale study from Stanford last month that said that organic foods aren't necessarily healthier? The study has spurred a raging debate between organic food advocates and skeptics who think conventional produce is just as safe and wholesome.
A discussion on Dr. Oz's popular television show earlier this month represented the pro-organic position. Dr. Oz said we simply shouldn't believe the Stanford study. He said all the headlines got it wrong. Dr. Oz wants us to eat organic food because he thinks the pesticides used in conventional farming put us at risk, while organic food – even though pesticides are used to grow it too – are safe.
Dr. Oz's unopposed guest, Dr. Alan Greene, said, "Organic food by definition is grown without 'toxic synthetic pesticides.'"
Wait a second. Is organic food really grown without synthetic pesticides? No. The USDA permits organic growers to use approved synthetic pesticides. The USDA's National Organic Program states, "In general, synthetic substances are prohibited unless specifically allowed and non-synthetic substances are allowed unless specifically prohibited."
Even organic food advocates admit pesticides are used on organic food. Jeff Gillman, a professor of nursery management at the University of Minnesota, told NPR's "Shots" blog last year, "When people are buying organic food, they often make the incorrect assumption that there are no pesticides."
Additionally, low levels of approved synthetic pesticides (e.g., pesticide residues found on food) are completely safe for consumers, both on organic and conventionally-grown produce.
So, Dr. Greene and Dr. Oz are wrong. Yet, if you still buy into their faulty logic, then you would be forced to conclude that the trace levels of pesticides used on organic produce are also toxic. Essentially, all food grown on farms is poisonous.
Of course, that's not true, so where do these fears come from? Often clumsy experiments that show that high-level exposure in lab animals causes cancer and other negative health outcomes.
Toxicologists rely on the maxim that "the dose makes the poison." Organic activists appear to reject this for conventional food but hypocritically embrace it for organic food. Dr. Oz found two different types of pesticides in organic peaches. That was okay, but he grandstanded when he found "seven pesticides… seven!" on conventional peaches.
Scientific American raised the same question Dr. Oz did: Are lower pesticide residues a good reason to buy organic? The piece, by Christie Wilcox, explains that the answer is a resounding "no." Wilcox explained:
Organic pesticides pose the same health risks as non-organic ones. No matter what anyone tells you, organic pesticides don't just disappear. Rotenone is notorious for its lack of degradation, and copper sticks around for a long, long time. Studies have shown thatcopper sulfate, pyrethrins, and rotenone all can be detected on plants after harvest—for copper sulfate and rotenone, those levels exceeded safe limits. One study found such significant rotenone residues in olives and olive oil to warrant "serious doubts…about the safety and healthiness of oils extracted from drupes treated with rotenone."
You won't hear Dr. Oz or his guests talking about how rotenone, perhaps the most widely used organic natural pesticide, is linked (but not causally) to Parkinson's Disease. (But they will hype other studies that propose possible links between conventional food and negative health outcomes.)
What's worse, because it is "natural," rotenone's usage isn't monitored like more carefully studied synthetic pesticides, and we therefore don't actually know how much of it we are exposed to. The USDA's Pesticide Data Program (PDP), in cooperation with state agriculture departments and other federal agencies, "manages the collection, analysis, data entry, and reporting of pesticide residues on agricultural commodities in the U.S. food supply, with an emphasis on those commodities highly consumed by infants and children." Yet, as Scientific American's Wilcox explains:
...while the PDP has been looking at the residues of over 300 pesticides in foods for decades, rotenone and copper sulfate aren't among the usual pesticides tested for—maybe, because for several organic pesticides, fast, reliable methods for detecting them were only developed recently. And, since there isn't any public data on the use of organic pesticides in organic farming (like there is for conventional farms), we're left guessing what levels of organic pesticides are on and in organic foods.
Dr. Oz and his pro-organic allies effectively appeal to our fear of chemical pesticides, no matter how unwarranted that fear is. The notion that organic food will protect us from evil "chemicals" represents a misunderstanding of toxicology, as well as of organic agriculture and how it is regulated. If you fear chemical pesticides and want them tightly monitored and regulated, you are, perhaps ironically, actually better off consuming conventional agriculture.
The wisest path to health is to consume a highly varied diet rich in fruits and vegetables, conventionally grown or not. Because conventional produce is just as safe and nutritious as organic, and tends to be less expensive, health advocates owe it to the public to quit tipping the scales for organics.
Jeff Stier is a Senior Fellow at the National Center for Public Policy Research in Washington, D.C., and heads its Risk Analysis Division.