A few weeks ago in Weekend Link Love, I mentioned the great big much-ballyhooed study that appeared to show organic produce was no more healthy than conventional produce. Many people with an axe to grind championed its findings, with some proclaiming the undeniable ringing of the final death knell of organic farming. Science Based Medicine wasted no time in weighing in on the current state of organic food, which they said “represents the triumph of marketing over scientific reality.” Strong words, words that seem to be – at first glance – supported by the study in question. But are they? Are you falling for marketing hype when you buy organic? Is it worth it?
Today, I’m going to discuss the impact of organic and conventional food on two aspects of wellness: fetal health and development and antibiotic resistance. I’ll follow this post up with more articles in coming weeks on the differences between organic and conventional food, and give my opinions on their impact on your health so that you can make an informed decision for yourself. Consider this Part 1 in a series.
It may be that humans are able to withstand chronic, low-level pesticide exposure without any glaringly negative health effects arising. Heck, maybe the occasional shot of organophosphate pesticide provides a hormetic, net-beneficial effect (I wouldn’t bet on it)! But what about the kids, the tots, the fetuses, the embryos? Might it be possible that what bounces off the thick manly hide of a fully-developed adult human with nary a flick of the eye could throw a wrench in the gears of fetal development? Perhaps the unabashed skeptic who instead of rinsing pesticides off his peach with water rinses water off his peach with pesticides can get away with it, while the pregnant woman craving peaches and Greek yogurt would be better off going organic. I suspect it might.
Earlier this year, a guy named David Bellinger also suspected it might, and so he looked at several studies which examined the relationship between prenatal exposure to organophosphate pesticides (in addition to other environmental pollutants) and cognitive development:
In one study, a ten-fold increase in DAP urine metabolites of pregnant women (the more organophosphates you take in, the more DAP urine metabolites you produce) meant a 4.25 point loss in IQ of their children.
Another study found that the same increase was associated with a loss of 1.39 points.
And in 2007, researchers found that “prenatal levels of organophosphate pesticide metabolites are associated with anomalies in primitive reflexes [in the children], which are a critical marker of neurologic integrity.”
Bellinger didn’t cover them all, though. There’s considerable evidence that chlorpyrifos, a pesticide often used on apple crops, causes brain abnormalities – thinning in some areas, enlargements in others – in children with significant prenatal exposure. Fetal organophosphate exposure has also been linked to ADHD (especially in boys).
Of course, these studies can’t establish causality, and it would be unethical and highly illegal to conduct controlled trials in which pregnant mothers were dosed with pesticides and fungicides to see how their offspring were affected, but we can look at animal studies to get an idea. Although the results are a bit mixed, this review (PDF) generally concludes that the older studies on organophosphate pesticides found them to be “safe,” while the more recent animal studies find evidence of mutagenic and teratogenic effects, particularly on the fetus.
So, does eating organic food reduce exposure to these organophosphates? After all, detractors love to tell us how organic farmers still use organic pesticides – a fair point. That said, as told in a 2006 Pediatrics study, an organic diet significantly reduces a child’s exposure to organophosphate pesticides as measured by the same DAP urine metabolites mentioned in the studies above. In fact, after just a few days of the organic diet, children in the study had virtually eliminated traces of urine metabolites. A 2008 study by the same author reached the same conclusions: switching to an organic diet can drastically reduce pesticide metabolites in kids.
It seems pretty cut and dry to me. DAP urine metabolites correlate strongly with deficits in cognitive development. In controlled studies using animal models, dosing rodents with organophosphate pesticides impairs fetal development. In controlled studies using human children, organic diets essentially eliminate DAP urine metabolites. Is there a smoking gun? No, I suppose not, but I do detect the distinct odor of burnt gunpowder. What about you?
As I mentioned in a post from last year, microbes are living, evolving things; when antibiotics are employed to get rid of them, they’ll often develop antibiotic resistance by two primary methods. First, basic natural selection: those microbes that can survive the antibiotic will reproduce, thereby passing on their fitter genes. And then there’s antibiotic resistance by horizontal gene transfer: once a microbe has gained resistance to an antibiotic, the gene that codes for that resistance can be horizontally transferred to other species of microbes. To get rid of the new and improved microbes, novel antibiotics – and more of them – will be administered, but even if this works, the microbes eventually become resistant to the new stuff, too, and the escalation of the situation continues.
Unless you’re talking about organic. Organic livestock never receive antibiotics (if they do, they must be shipped off to slaughter as conventional food, or sold to a conventional producer), whereas conventional farming often employs antibiotics to stimulate weight gain in otherwise healthy livestock. A recent study found antibiotic-resistant bacteria on half of US grocery store beef, chicken, pork, and turkey that were conventionally-raised. And in 2011, a study found that pigs fed antibiotics soon developed a drastically altered intestinal microbiota that converted feed into energy more efficiently (it made them fatter), had a greater proportion of resident E. coli, and showed evidence of increased antibiotic resistance – even to antibiotics that were never administered! Meanwhile, organic meat shows up with far less antibiotic-resistant bacteria, and one recent study even showed that converting a conventional poultry farm into an organic poultry farm began reversing antibiotic resistance within a single year.
Now, it’s true that as long as you cook your meat well and avoid ground meat that you don’t trust (well-done steaks and no more hamburgers – sounds great, doesn’t it?), you probably don’t have to worry about any personal, immediate health risks from consuming conventional meat contaminated with antibiotic-resistant bacteria. But what about the long game? What about the fact that otherwise harmless bacteria who’ve learned to resist antibiotics might pass their knowledge onto virulent bacteria? What about the fact that many officials are calling drug-resistant bacteria the next major global health threat?
I hope I’ve given you some (organic) food for thought. For now, ruminate on this post, but don’t make any rash decisions. Don’t freak out, no matter how scary the data might seem. Next week, I’ll explore the widely held claim that organic produce is no more nutritious than conventional produce to see if it holds up.
Take care, folks. Thanks for reading.