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Research shows little evidence that organic foods are more nutritious than conventional ones

Research shows little evidence that organic foods are more nutritious than conventional ones

I have a confession. I’m the mom of two young girls, and I don’t always buy organic. Okay, I barely ever do. You may be thinking, “So what?,” but in the pocket of the world in which I live, this is a big deal. Many (most?) people who afford it buy it. And some parents who do buy it look down upon those who don’t. (Don’t believe me? Come to the playground and watch as I tell some of the moms that the banana my 3-year-old is snacking on is not organic. You’ll see what I mean.)

Here’s the thing: I do buy nutritious food for my kids, and I try to instill in them healthy-eating habits. I love them and want the best for them, obviously, but I’ve never quite been able to justify buying organic. (Other people don’t seem to have the same problem: Between 1997 and 2011, U.S. sales of organic foods – which sometimes cost twice as much as their conventional cousins – increased from $3.6 billion to $24.4 billion.) Perhaps it can be blamed on my Midwestern frugality, or my tendency to reject things that I feel are being shoved upon me – hence my not wanting/having an iPhone, for example. But the bigger truth is that I haven’t been convinced that organic food is that much better for a person, from a health perspective. (Show me the proof, and I’ll open my wallet.)

Now, with today’s publication of a study on the health benefits and risks of organic foods, I feel like I have a little ammunition to use against the judgmental moms. Researchers here did the most comprehensive meta-analysis to date of existing studies comparing organic and conventional foods and found little evidence that organic foods are more nutritious or carry fewer health risks than conventional alternatives. (They did find, not surprisingly, that consumption of organic foods reduces one’s risk of pesticide exposure, but even the conventional foods generally fell within the allowable safety limits.) As I explain in our release about the Annals of Internal Medicine paper:

No consistent differences were seen in the vitamin content of organic products, and only one nutrient — phosphorus — was significantly higher in organic versus conventionally grown produce (and the researchers note that because few people have phosphorous deficiency, this has little clinical significance). There was also no difference in protein or fat content between organic and conventional milk, though evidence from a limited number of studies suggested that organic milk may contain significantly higher levels of omega-3 fatty acids.

The researchers were also unable to identify specific fruits and vegetables for which organic appeared the consistently healthier choice, despite running what [senior author Dena Bravata, MD, MS, a senior affiliate with Stanford’s Center for Health Policy and a chief medical officer of Castlight Health] called “tons of analyses.”

“Some believe that organic food is always healthier and more nutritious,” said [first author Crystal Smith-Spangler, MD, MS]. “We were a little surprised that we didn’t find that.”

During recent conversations, both researchers emphasized that their aim isn’t to discourage people from buying organic if they want to do so – there are, after all, other reasons to choose organic besides health considerations. What they’re instead aiming to do is provide clarity on a previously murky area and, in turn, help inform choices made in the supermarket. “This is information that people can use to make their own decisions based on their level of concern about pesticides, their budget and other considerations,” Smith-Spangler told me.

As for me, I’m hoping the findings equate to fewer dirty looks on the playground.

Previously: When it comes to nutritional value, debating “organic” vs. “conventionally grown” may be beyond the point, Organic vs. natural: Tips for parents who want to go green, “Natural” or not, chicken nuggets are high in fat, sodium and People equate “organic” with “healthy,” risking poor food choices
Photo by mikecogh

11 Responses to “ Research shows little evidence that organic foods are more nutritious than conventional ones ”

  1. sharon w Says:

    I agree, it’s expensive and hard to know what really matters. There are a few things I buy organic after reading that the farmers that grow them won’t feed them to their own families, I recall there were about 6. Potatoes,strawberries, apples, and spinach are some of the most heavily laden with pesticides(potatoes get sprayed 3X) and I will opt for organic on those items.

  2. mark stephens Says:

    The judgmental moms might be merely speaking the truth as they understand it, such as that it is not healthy to put pesticides into your body or into one’s children’s bodies.

    You may have missed these passages from the researcher’s published synopsis:

    “Two studies reported significantly lower urinary pesticide levels among children consuming organic versus conventional diets.”

    “The risk for contamination with detectable pesticide residues was lower among organic than conventional produce (risk difference, 30% [CI, −37% to −23%]).”

    “The risk for isolating bacteria resistant to 3 or more antibiotics was higher in conventional than in organic chicken and pork (risk difference, 33% [CI, 21% to 45%]).”

    Do you want to eat foods laden with pesticides, antibiotics and unknown chemicals, or organics that are free of these substances?

    Do note the brevity of the research and compare it with more longitudinal studies on the effects of pesticides and antibiotics.

    Posing the question as one of “nutrition” rather than “health” highlights the relative similarity in nutrients while ignoring the larger and longer term effects on health.

    Meanwhile, conventional food production exposes workers to sometimes carcenogenic levels of pesticide exposure.

    Please consider revisiting your position on this question.

    Organics are better for you.

  3. doug f Says:

    Remember that nutrient content is not the primary issue — pesticides and chemical runoff are. GMOs are the other problem and it’s a bigger problem than organic vs. non.

  4. FarmersDaughter Says:

    Finally, a study that proves what we’ve been telling people: overpriced organic food has no health benefits over conventionally grown food. This myth has been perpetrated and is scamming our families.

    @SharonW: I still live on my family’s farm. We grow potatoes, apples, and strawberries. We also spray them. I also eat them. No farmer produces food that they themselves would not eat. What we produce we feed to our families too. Where ever you heard that information it is absolutely false.

  5. Stanford study on the health benefits of organic food: What people are saying | Scope Blog Says:

    […] of media attention that our organic-food one has gotten. (In case you missed it: Researchers here found little evidence of health benefits from organic foods. Senior author Dena Bravata, MD, MS, told one […]

  6. Kyle Says:

    We are part of a childbirth education company and we have learned a valuable lesson in research – meta analyses is a dangerous thing. It is rarely appropriate to compare study to study and lump data together, there is too much variance and it is just misleading.

    Our research has led us to another important conclusion – in many cases organic farming is more sustainable than current conventional methods.

    Let me be clear – this is only true in SOME organic producers, organic is a very loose term and there are definitely producers that take better care of the land they grow on and as a result they do produce higher quality food. I would like to see a study on organic definitions and standards…

  7. Stanford researcher chats live about the health benefits of organic foods | Scope Blog Says:

    […] Previously: Stanford study on the health benefits of organic food: What people are saying and Research shows little evidence that organic foods are more nutritious than conventional ones […]

  8. Arden Nelson, DVM Says:

    On our web site,, we have several reviews of studies that show the importance of caring about pesticide exposure. One example is the California study of the association between pesticide exposure and autism spectrum disorders.

    Study conclusion:In this study, the results indicate that the chances of ASD development for any exposure was 6.1 times the rate in unexposed fetuses. More specifically, fetuses exposed to the highest level of pesticides during the critical period of neural tube closure were 7.6 times more likely to subsequently be diagnosed with ASD. This is 760% higher ASD rate than expected!

    Complete Study is available online at (, with DOI number of 10.1289/ehp.10168

    Whether you read our synopsis or the whole study report, I will bet that this study will get your attention and may bring about behavior changes that you may want to instill in your daughters…

  9. Arden Nelson, DVM Says:

    Mark Stephens,

    You may want to visit here —
    to read Dr. Charles Benbrook’s Response to the Stanford Organic vs Conventional Study.

    Perhaps you should google his name to evaluate his credentials in this arena, too.

    He very clearly shows that the math used by the 12 Stanford researchers is really misleading and totally outside the normal risk calculations made by both typical researchers and the simple folk, like I am.

    In reality, organic produce in this Stanford study was 81% less likely to contain pesticides than the conventional produce.

    Likewise, organic poultry and pork was 67% less likely to contain antibiotic resistant bacteria than conventional poultry and pork.

    Best of health to you and yours through perspective enhancement!

  10. Kristie Says:

    Good for you! It’s ok if you don’t buy foods with that 7-letter word; “organic”. An apple is an apple. Just because it may have been grown using organic production methods doesn’t mean it has more nutritional value than an apple grown using conventional production methods. Regardlesss of how farm products are raised, consumers still need to use proper preparation methods: wash your produce, avoid cross-contamination, cook meat thoroughly, wash hands, etc.
    I don’t buy organic, and I love my family just as much as people who do buy organic.
    Thanks for your honest post.

  11. Mike Says:

    I’m not convinced that conventionally grown is nutritionally equal to and/or safer than organic.
    But there is one argument favoring organic over conventional that needs more press. Buying organic helps reduce the overload of pesticides, insecticides and herbicides, all of which are proven carcinogens. The future savings in healthcare is well worth it. The cost of treating cancer can cost upwards of $4,000 per day or more. Been there, done that, got the T-Shirt, not going back!


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