Organics, GMOs and your gut
Are organic foods better for your gastrointestinal (GI) system than non-organics? Most published research at this time doesn't specifically look at GI outcomes, but let's start with the best quality data and go from there.
Are organic foods better for your gut?
Two large reviews cast early doubt on the benefits of organic foods. In both cases, researchers compiled existing studies, and found minimal significant difference in health benefits between organic and conventional foods. While organic produce had a 30% lower risk of pesticide contamination than non-organic, both pesticide levels fell within safety limits and there was no added nutritional benefit with organics. An important point, however, is that very few of the studies incorporated into the reviews actually focused health outcomes. In non-pregnant adults, for example, only 1 of the 11 studies looked at clinical data, and none of them directly compared pesticide levels found in humans. Additionally, there was a significantly more antibiotic resistant bacteria found in non-organics compared to organics.
Are organic foods more nutritious?
Most studies have been geared more towards looking at the nutritional differences of organics (i.e. higher healthy omega fats in organic dairy products), and not necessarily the clinical harms of non-organics. For now I'm going to put aside discussing research comparing nutritional benefits, because my take away is that while there definitely are some benefits to organics, it is unclear if these differences simply based on nutrition alone are enough to actually affect your health.
Are pesticides in non-organic foods dangerous?
But that's not to say that there aren't other health implications to consider. The most recent of those reviews was published in 2012, and since then there's been more of a focus on how pesticides affect our health. A review in 2014 showed organics had significantly lower levels of pesticides and cadmium, a metal that in high amounts can be toxic to the liver and kidneys.
The most commonly discussed pesticide in recent literature has been glyphosate, more commonly known as Roundup. The 250 fold increase in its use over the past 40 years coupled with a World Health Organization affiliate's label (and sudden retraction) of glyphosate as a "probable carcinogen" has led to intense debate over the cancer risks of pesticide use. Despite individual studies claiming glyphosate can cause anything from celiac to autism, consensus at this time is that the amount of glyphosate we get through our diet has not been shown to pose health risks.
Lastly, a few caveats. There is surprisingly little data on how newer formulations including glyphosate affect human health, and we are still in the very early stages of truly understanding the gut microbiome (our article here), but the increased antibiotic use in non-organics is certainly worth considering when deciding for yourself.
Are genetically modified organisms (GMO's) safe for the gut?
Yes. The overwhelming data in human studies does not suggest GMOs pose any threat to the gut. That is the stance held by Nobel laureates, the National Academy of Sciences, and the American Medical Association, among many others including the World Health Organization. Interestingly, the dissonance between public perception and quality of data supporting this stance is stark: over 88% of scientists believe in the long-term safety of GMOs versus only 40% of the general public sharing the same belief. Is science all-knowing? No. But if the data was equivocal there would be less general consensus from the same impartial scientific organizations that take the same defiant stance against global warming despite the economic pressures to relent.
My approach? Being mindful of foods I eat in high quantities, and cross-referencing that with foods with high pesticide content. In general, I don't seek out organics, and never select for non-GMOs, but for foods like spinach and apples that I eat in high quantities to improve my fiber intake I generally opt for organics when available. That said, we still have a lot to learn and I welcome any questions you have on the topic through the Q&A section of our website!
-The Gut Doc
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