Guess what? Organic really is better | Chris Kresser
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Guess What? Organic Really Is Better.


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For some reason that isn’t clear to me, the mainstream media and medical establishment seem very attached to the idea that organic produce is no healthier or safer than conventional produce. 

They often point to a study performed at Stanford in 2012 as proof of this claim, as if it were the final word. After all, it’s Stanford! 

New study confirms that organic produce is higher in antioxidants and lower in pesticide residues.

But it turns out the Stanford study wasn’t nearly as conclusive as the media made it out to be. I wrote an article critiquing it shortly after it was published, and Mark Sisson also weighed in.

In short, the Stanford researchers inexplicably omitted or undervalued certain nutrients from the comparison that have already been shown to be more concentrated in organic foods, such as vitamin C, polyphenols, and flavonoids. What’s more, according to the researchers own conclusion, “consumption of organic foods may reduce exposure to pesticide residues and antibiotic-resistant bacteria.” (1)

New Analysis of 343 Studies Finds That Organic Really Is Better

A new study published in the British Journal of Nutrition is the latest addition to the debate. It’s the largest meta-analysis (i.e. review of studies) that has been published on this topic to date, covering 343 individual studies looking at the composition of crops and food. (2)

The study found that organic crops had higher levels of certain antioxidants—such as phenolic acids, flavonols and anthocyanins—and that eating organic foods could boost a person’s antioxidant intake by up to 40% (the equivalent of two portions of fruits or vegetables a day).

Some “experts” have claimed these results are meaningless because “antioxidants are not essential nutrients.” But while antioxidants in plants may not be essential, in the sense that we cannot live without them, a growing body of evidence suggests that they are crucial for optimal health. 

In fact, recent research has revealed that what we call “antioxidants” in plants are actually “pro-oxidants” that gently stress our bodies. Rather than killing us or making us sick, however, these compounds promote adaptations that make us healthier and stronger and may extend our lifespan. The science writer Moises Velasquez-Manoff describes this phenomenon in a recent article called “Fruits and Vegetables Are Trying To Kill You:

…these plant “biopesticides” work on us like hormetic stressors. Our bodies recognize them as slightly toxic, and we respond with an ancient detoxification process aimed at breaking them down and flushing them out.

Consider fresh broccoli sprouts. Like other cruciferous vegetables, they contain an antifeedant called sulforaphane. Because sulforaphane is a mild oxidant, we should, according to old ideas about the dangers of oxidants, avoid its consumption. Yet studies have shown that eating vegetables with sulforaphane reduces oxidative stress.

When sulforaphane enters your blood stream, it triggers release in your cells of a protein called Nrf2. This protein, called by some the “master regulator” of aging, then activates over 200 genes. They include genes that produce antioxidants, enzymes to metabolize toxins, proteins to flush out heavy metals, and factors that enhance tumor suppression, among other important health-promoting functions.

Some scientists have even gone as far as suggesting that antioxidants (or more accurately, “pro-oxidants”) are primarily responsible for the health benefit we get from eating plants. Thus, the finding that we may get 40% more antioxidants from eating organic produce is not insignificant. 

Pesticide Residues and Toxic Metals Are Not Harmless

In addition to finding higher levels of antioxidants in organic produce, the study authors also found lower levels of cadmium—a toxic, heavy metal—and lower levels of pesticide  residues. On average, cadmium and pesticide levels were 48% and 400% lower, respectively, in organic produce than in conventional varieties.

Cadmium (Cd) is a highly toxic metal that accumulates in the human body. It is classified as a category I carcinogen—which means it contributes to cancer development—and has been linked to an increased risk of everything from Alzheimer’s disease, to thyroid problems, to cardiovascular disease, to hormone imbalance. (3, 4, 5, 6) It’s fairly obvious, therefore, that we should do everything we can to minimize our exposure to cadmium.

The question of how exposure to pesticide residue in foods impacts human health is still controversial. That said, there is more than enough evidence to warrant caution—and that is especially true for children and pregnant women. Reports over the past few years have linked pesticide exposure in children to ADHD, intelligence/IQ, and numerous other problems. Researchers have also begun to identify mechanisms through which pesticides can disrupt the development of children even at very low exposures. (7)

Why Local Trumps Organic When It Comes to Nutrient Content

As I’ve argued before, the most significant factor in determining the nutrient content of fruits and vegetables is not whether they are grown organically or conventionally, but how long they have been out of the ground before they are consumed. 

Most of the produce sold at large supermarket chains is grown hundreds – if not thousands – of miles away, in places like California, Florida and Mexico. This is especially true when you’re eating foods that are out of season in your local area (like a banana in mid-winter in New York).

The problem with this is that food starts to change as soon as it’s harvested and its nutrient content begins to deteriorate.

Total vitamin C content of red peppers, tomatoes, apricots, peaches and papayas has been shown to be higher when these crops are picked ripe from the plant. (8) This study compared the Vitamin C content of supermarket broccoli in May (in season) and supermarket broccoli in the Fall (shipped from another country). The result? The out-of-season broccoli had only half the vitamin C of the seasonal broccoli. (9)

Jo Robinson goes into great detail on this topic in her excellent book, Eat On The Wild Side. In fact, she argues that the fruits and vegetables we eat today are almost unrecognizable to what our ancestors ate in terms of nutrient content, in part because of the effects of industrial food production.

So while it certainly makes sense to eat organic, if you’re interested in maximizing the nutrient density of your food, eating foods that are grown locally and consuming them as close to harvest as possible is even more important. This means shopping for produce at farmer’s markets or using a CSA, or even better, growing your own backyard fruits and veggies. 

Final Thoughts and Recommendations

Before I share recommendations, it’s worth pointing out that this new study was funded by the European Union and the Sheepdrove Trust, an organic farming charity. One might argue that the involvement of the Sheepdrove Trust constitutes a conflict of interest.

Unfortunately, such conflicts are the rule rather than the exception in most nutritional and medical research. Critics of the Stanford study have pointed out that the Freeman Spogli Institute, which supported the research, has received millions of dollars in funding from Cargill (the world’s largest agricultural business) and the Bill & Melinda Gates Foundation, which has deep ties to agricultural and biochemical companies like Monsanto. In addition, one of the co-authors of the study, Dr. Ingram Olkin, has accepted money from the tobacco industry’s Council for Tobacco Research, which is a fraudulent front organization for Big Tobacco. 

When a study is funded by an organization with a vested interest in the result, we should certainly be cautious when interpreting those results. However, such a funding source does not by definition make the study worthless. We can still evaluate it on its own merits. 

With that in mind, I think the findings of this new, large study are sound and consistent with the majority of the previously published evidence—especially as it relates to higher levels of pesticide residue and heavy metals in conventional produce. 

Here’s what I’d suggest given what we know:

  • Buy organic, locally grown produce as much as possible. This typically means shopping at farmer’s markets and/or joining a local community supported agriculture (CSA) program.
  • It’s particularly important for young children and women who are trying to conceive, pregnant, or breastfeeding to eat organic, because they are more susceptible to being harmed by pesticide residue and heavy metals.
  • If you have limited access to organic produce, due to financial or geographical reasons, try to at least buy organic varieties of the fruits and vegetables that are grown with the highest amount of pesticide when grown conventionally. The Environmental Working Group maintains a list of these, which it calls the “Dirty Dozen”. It also maintains a list of the “Clean Fifteen”, which are the fifteen varieties of fruits and vegetables that are relatively safe to buy conventionally. You can see both lists here.
  1. “On average, cadmium and pesticide levels were 48% and 400% lower, respectively, in organic produce than in conventional varieties.”…

    400% lower? What could that possibly mean? Chris, please tell me you didn’t mean to say that!

  2. The most recent analysis is not much different than the 2012 meta-analysis nor the one before that ( All have showed that some organic foods have microscopically more nutrients and some have fewer. Some have microscopically fewer pesticide traces than conventional. (It is important to note that the USDA NOP does not require field testing of organic produce so, commercially, it is difficult to know what we’re buying.) No long-term studies have been done to determine whether that translates to better health outcomes.

    The other thing is, there are so many variables in region, weather, and native soil that nutrients can vary within same types of crops from harvest to harvest.

    The California Dept of Ag is one of the most transparent agencies when it comes to food. It’s interesting to read their pesticide data reports and to see that many conventional crops have been sprayed with the pesticides used in organic farming, with sulfur being one of the most commonly used pesticides in both conventional and organic (sulfur is allowed in organic).

    As far as the EWG “dirty dozen”, it uses some fuzzy math to come up with its numbers, by combining what has been used over multiple years. For instance, if broccoli was sprayed with atrazine in 2001, and then with glyphosate in 2008, and then Spinosad in 2013, EWG will state broccoli was found to have three residues, and put it on the dirty dozen list.

  3. Excellent article, Chris, and long overdue. Thanks for informing us so well.


  4. I’d be interested in hearing your views about this episode of The Checkout, a consumer advice program on Australia’s public broadcaster (ABC). It does a thorough hatchet job on organic food, and concludes that “If you’re gonna pay a lot more for a little ‘feel good’ factor, you should at least make sure it feels real”.

  5. I live in SC and farmers markets are not the best in the country. But I did my due diligence and found local farmers who, even though they don’t have the organic certification, grow organically. I even bought soil from my farmer and I’m now growing my own veggies.

  6. Just want to point out – “If you have limited access to organic produce, due to financial or geographical reasons, try to at least buy organic varieties of the fruits and vegetables that are grown with the highest amount of pesticide. ” I think you meant least amount of pesticides. 🙂 And you don’t have to put this up on the comment board.

    • A few people seem confused, but he means that you should figure out which vegetables are conventionally grown with the most pesticides, then try to buy those particular fruit/veg from organic producers.

  7. I am interested in learning more about the heavy metal residues, such as cadmium, mentioned in the article. we all know about the “dirty dozen” for pesticide residue- does that go hand in hand with heavy metal residue? if not, which crops are the ones to stingily avoid, not just for pesticides, but for the heavy metal exposure? ? ? i think i read somewhere that iceberg lettuce was a bad one for cadmium, but what else to avoid….?

  8. Love that you cited Eat on The Wild Side, but I don’t believe you meant to say modern fruits and veggies are indistinguishable from their ancestors — the book argues exactly the opposite.

  9. My home-grown organic fruits and vegetables taste so incredibly good that I now hate to eat most store-bought produce.

    It’s quite possible to grow most of the vegetables that you eat on a Paleo diet (well over half) in less than 200 square feet of garden beds. It’s also possible to harvest fresh vegetables 12 months a year – even in cold climates! And you don’t need a fancy greenhouse to do it, either.

    • I don’t mean to sound rude, but honestly, I’m tired of people saying this. If you can do this then I’m glad you can, but while I have a rather large yard, almost none of it gets much direct sunlight thanks to large trees all around us. If you mean that you can grow all the sorrel you want for your paleo diet in your yard, then I’d agree with you, but otherwise, nope. Most of the vegetables we want to grow require more sun than we can give them. And I wouldn’t even consider life without these big trees around me even though they shade out my garden areas.

      • If you really want to have a vegetable garden, no one is saying that you have to have the garden in your own yard. If you live in an apartment, or have a shady yard, it’s often possible to arrange to have a sunny garden patch with a friend or neighbor, or in a community garden. You can even ask for space through Craigslist or a sign at a local food coop. There are people that would love a share of fresh vegetables in exchange for someone gardening in their yard.

      • Debra is just trying to encourage people into creating a better life for themselves. If you really wish to give yourself the benefit and pleasure of home grown organic food, stop wasting time by focusing on what’s in your way, But instead, taking all that energy into clearing away the trees blocking your light.

    • Perhaps the best way to find out if organic is better is to do as Debra suggest and grow your own. My sister and I have always been at odd with each other. No matter what I get into, she would oppose it. When I started eating organic, she would mock my decision and say I don’t believe that there is any different.

      Then one day a group of organic farmers approached her to ask whether she would allow them to grow organic vegetables in her garden to sell at the farmer’s market in exchange for all the vegetables she could eat. My sister, but the deal didn’t work out, because the vegetables were not the type that my sister liked and she finally told them that this deal was not going to work out. Meanwhile, the farmers had already transformed her garden to organic. Rather than letting it go to waste, my sister just planted vegetables that she liked, but organic ones.

      As I said, no matter what I tell my sister, if I’m for it, she will absolutely oppose it. That and the fact that we live about 8 hours drive apart, I seldom see her. When I finally saw her about a year or so later, I was totally blown away by how good she looked. Her skin was so much softer and much younger looking.

      So, I don’t need an article to tell me organic is better, here is a person, who absolutely does not think there is a difference, never even bought organic, but when an organic garden was placed in her home and she ate from it, she became younger. I don’t think any article and tests, mainly funded by organizations with agendas are going to be half as effective as getting your own garden and trying it yourselves.

    • yeah, i agree. i grew some savoy cabbage a few years ago just for kicks and it was so delicious to make a coleslaw from it and some fresh lemons picked right from the tree. The cabbage in the supermkt is so bland, has no taste at all.

  10. Helpful analysis of the scientific literature (as always). I follow your recommendations of buying local and organic as much as possible and think eating organic is really important. One thing I’ve ran into is the argument that antioxidants don’t matter – specifically Melinda Wenner Moyer’s “The Myth of Antioxidants” in Scientific American about a year ago. Can you comment on this?

  11. Good article, it is so important not to feed pesticide laced food to our nursing mothers and little children. Thank you for bringing it to our attention.

    Organic produce might be a bit more expensive, but what is your good health worth?

  12. Great article, but I think you mean “the fruits and vegetables we eat today are almost UNRECOGNIZABLE when compared to what our ancestors ate” . . . The book “Eating on the Wild Side” argues that the produce we eat now is much LESS nutritious than what our ancestors ate.

  13. Great article! Love how you break things down. FYI there’s a typo in the last bullet point…it says to buy fruits and veg with the “highest” amount of pesticide and I know you meant to say “least.”

    • There is no typo. If you read the _entire_ sentence you see that the use of “highest” is intended and correct.

    • Yes, it’s not a typo… Just worded slightly awkwardly. Chris is saying to buy produce grown organically, especially when the conventional variety has higher concentrations of pesticides (such as those on the dirty dozen).

  14. I love to shop at farmer’s markets. Both for the amazing local/organic produce as well as it being a very relaxing ritual. I have not quite noticed a difference in the way I feel with organic vs not, but I definitely notice a difference in taste. The early girl tomatoes in season now as well as the berries are so amazingly tasty!

  15. The beauty of living in SoCal is the abundance of farmers markets. It might be a tad pricier but it is well worth it in my opinion.

  16. In our hazelnut orchard we are in the transition from a more conventional approach to organic (and beyond). There is so much to be learned about soil biology and as an orchard grower – it just makes plan sense to invest in this change. We have some hurdles like replacing commercial fertilizer on a grand scale (for 225 acres) and rethinking how we work with hazelnuts trees (they grow more like a bush than a tree). There are so many that can benefit and not just us humans – how about earthworms and fungi? Thank you for continuing to educate us on making better choices for ourselves and the planet.

    • Thank you for making the commitment to organic farming. It is no small undertaking but well worth the effort. And congratulations for discovering the amazing world of soil microbes and fauna! May you continue to be in awe of the incredible world we live in!

  17. Hi Chris,

    Great article! The importance of fresh and local produce is certainly very important. The differences between it and conventional are just too significant to be ignored, especially in the long term.

    How does organic frozen produce stack up against local produce in terms of nutrition?

  18. I more or less stopped eating vegetables for a while because they were making me sick. I had subconsciously started making what appeared to be very poor food choices e.g. fried foods vs. a salad. Then I went on a trip to Greece–where I was more or less forced to eat salad at every meal since most restaurants charge you extra for the salad whether or not you eat it. I rediscovered joy in eating vegetables and remembered that I used to love salads.
    Then I returned to America. I tried eating salads in restaurants and buying conventional vegetables. I found that I would get welts on my tongue after consuming small quantities of lettuce and other vegetables. My tongue would get tingly and numb and soon get welts. I tried organic produce and low and behold–no welts or tingly tongue!
    Probably fairly obviously there is a whole lot more to my health story than just the organic vs. conventional vegetables issue, but my experience has been fairly dramatic, so people may be interested.

      • Don’t be such a coward. If you want to give a negative comment, explain what you mean. Don’t just put a damper on it.

      • Emmett, Apparently you missed the place that I said, “Probably fairly obviously there is a whole lot more to my health story…” Of course there is something missing–a whole lot of some things! However, I thought that this part of the story was relevant to this article and might be interesting and useful to some readers.
        It was in fact this problem with many conventional vegetables that helped me get on the right track with my health.
        I have not yet met anyone else who actually consistently got welts on their tongue from eating fruits and vegetables, but I HAVE met a LOT of people who get some mouth tingling/mild numbness but hadn’t really thought about it. Perhaps my abbreviated story will help them become more aware and figure out what is causing the problem(s) for them.

        If you have a specific question and legitimate interest, I would be willing to share more information.

  19. The paleo/primal community tends to shun beans because of phytopesticides which may or may not be broken down with proper preparation. Please explain the difference here from consuming pro-oxidants in plants.

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