The stated principles of organic agriculture are “health, ecology, fairness, and care,” but if you ask people why they buy organic, the strongest predictor is concern for their own health. People may spend more for organic for more selfish, rather than altruistic motives. Although organic foods may not have more nutrients per dollar, consumption of organic foods may reduce exposure to pesticide residues and antibiotic-resistant bacteria.
Food safety-wise researchers found no difference in the risk for contamination with food poisoning bacteria. Both organic and conventional animal products have been found to be commonly contaminated with Salmonella and Campylobacter, for example. Most chicken samples (organic and inorganic), were found to be contaminated with Campylobacter, and about a third with Salmonella, but the risk of exposure to multidrug resistant bacteria—resistant to multiple classes of antibiotics—was lower with the organic meat. So they both may carry the same risk of making us sick, but food poisoning from organic meat may be easier for doctors to treat.
What about the pesticides? There is a large body of evidence on the relation between exposure to pesticides and an elevated rate of chronic diseases such as different types of cancers, diabetes, neurodegenerative disorders like Parkinson’s, Alzheimer’s, and ALS, as well as birth defects and reproductive disorders, but these studies were largely on people who live or work around pesticides.
Take Salinas Valley California, for example, where they spray a half million pounds of the stuff. Daring to be pregnant in an agricultural community like that may impair childhood brain development, such that pregnant women with the highest levels running through their bodies (as measured in their urine) gave birth to children with an average deficit of about seven IQ points. Twenty-six out of 27 studies showed negative effects of pesticides on brain development in children. These included attention problems, developmental disorders, and short-term memory difficulties.
Even in urban areas, if you compare kids born with higher levels of a common insecticide in their umbilical cord blood, those who were exposed to higher levels are born with brain anomalies. And these were city kids, so presumably this was from residential pesticide use.
Residential exposure to pesticides, like using insecticides inside your house, may also be a contributing risk factor for childhood leukemia. Pregnant farmworkers may be doubling the odds of their child getting leukemia and increase their risk of getting a brain tumor, leading authorities to advocate that awareness be increased among populations occupationally exposed to pesticides about their potential negative influence on health of children, though I don’t imagine most farmworkers have much of a choice.
So conventional produce may be bad for the pregnant women who pick them, but what about our own family when we eat them?
Just because we spray pesticides on our food in the fields doesn’t necessarily mean it ends up in our bodies when we eat it, or at least we didn’t know that until a study was published in 2006. Researchers measured the levels of two pesticides running through children’s bodies by measuring specific pesticide breakdown products in their urine.
In the video below you can see the levels of pesticides flowing through the bodies of three to 11-year olds during a few days on a conventional diet. The kids then went on an organic diet for five days and then back to the conventional diet. As you can see, it’s clear that eating organic provides a dramatic and immediate protective effect against exposures to pesticides commonly used in agricultural production. The study was subsequently extended. It’s clear by looking at the subsequent graph in the above video when the kids were eating organic versus conventional. What about adults, though?
Thirteen men and women consumed a diet of at least 80% organic or conventional food for seven days and then switched. And no surprise, during the mostly organic week pesticide exposure was significantly reduced, and not just by a little, a nearly 90% drop in exposure.
So it can be concluded that consumption of organic foods provides protection against pesticides, but does that mean protection against disease? We don’t know. The studies just haven’t been done. Nevertheless, in the meantime, the consumption of organic food provides a logical precautionary approach.