Field of Science

Organic foods aren't more nutritious

ResearchBlogging.orgSo if you purchase organically grown food (crops and meat) because you think they are more nutritious, then you might be disappointed to learn that there is no evidence that it is.

In a huge survey of the literature on organic food from the last 50 years, the overall message is that no difference in nutritional value is to be found between organically and conventionally grown foods. [1] (By the way, I hope some day those terms will be replaced by "conventional" for what is now termed organic, and "sprayed" or perhaps "chemical" for what is now called conventional.)

The only differences found was that conventionally produced crops had more nitrogen (that's good), and that organic crops had more phosphorus (an essential element for our cells). That's it!

So why do you buy organic food? I have also heard people say it's more healthful (actually, they say "healthier", but that's would be to the food), but I like to do it because it is better not to use pesticides, hormones, and antibiotics (anything else?), since those harm us, as well as other species, such as sexually challenged frogs [2]. If no one can find any evidence that those chemicals are bad for humans to ingest, then I would be very surprised (but then again, I wouldn't be surprised to be surprised).

[1] Dangour, A., Dodhia, S., Hayter, A., Allen, E., Lock, K., & Uauy, R. (2009). Nutritional quality of organic foods: a systematic review American Journal of Clinical Nutrition DOI:10.3945/ajcn.2009.28041


Update July 30th:
It is interesting to see the diversity of the few comments below. Tom points out that the study didn't look at micronutrients, Rachel remarks that organic farmers do in fact use pesticides and herbicides that are also not good for you, and an almost mandatory anonymous conspiracy-theorist comment that this study was funded by big agro (implying it has no validity). All I could find in the paper about finding was this:
2 The funding organization had no role in the study design, data collection, analysis, interpretation, or writing of the report. The review team held 6 progress meetings with the funding organization.
3 Supported by the UK Food Standards Agency (PAU221).
I have contacted the first author for a clarification.

Update july 31st:
Alan Dangour got back to me and confirmed that the UK Food Standards Agency was the only agency funding this study. That seems to put any concerns about big agro influencing the results to rest.


  1. This is really interesting, I didn't know there was no difference health-wise between organic and inorganic food.
    I think there is still good reason to buy organic, however. Most organic food is also fair trade and/or locally grown. That matters more to me than pesticide use.

  2. I suspect this was funded by international big ag corps like Monsanto and Cargill apart from major lobbies like FBU. it's not the nutrition about organics but the lack of harmful chemicals and growing methods to plants and animals for choosing organic and less harmful to the environment planetwide. This is just a tool for big business and monied concerns in world food production to prevent the increasing organic/natural markets from getting bigger and more profitable locally.

  3. Actually most organic farmers do you pesticides and herbicides. They use non-synthetic pesticides that are 'naturally derived. I point out frequently that poison oak and heroin are natural and certainly not good for you!

    here is a UN review of agriculture in which a majority of organic pesticides fail safety tests:

    organic foods keep looking less and less like they are worth the extra money and land.

  4. Looks like they didn't assess organic micronutrients - flavonoids and such like. These are the things that have the alleged anticancer and other helthy properties. The tend to be higher in organic foods because they're produced in response to stress.

  5. Hmm, it seems they did look at these:

    The Soil Association challenged the conclusions that some nutritional differences between organic and conventional food were not important. It said it was particularly concerned that the researchers dismissed higher levels of beneficial nutrients in organic food — such as 53.6 higher levels of beta-carotene and 38.4 per cent more flavonoids in organic foods — according to the mean percentage difference of samples analysed.

    Dr Dangour was adamant that these were not relevant because of the level of standard error in the research — which was 37 per cent for beta-carotene and 10.6 per cent for flavonoids.

    Hmm interesting. But a 10.6 SEM for flavonoids still suggests a significant difference.

  6. Please see new updates at the bottom of the post.

  7. Thanks for the pointer. A shame they didn't measure contaminants or chemical residue.

  8. A shame they didn't measure contaminants or chemical residue.

    Indeed, that would probably affect more people's choices, since I suspect that not too many people go for organic because they expect it to be more full of nutrients, but rather less full of chemicals.

    Note, this was a review study. A similar review could be done for chemical residues, I suppose.

  9. if farmers didnt use pesticides then most of the foods wouldn't even make it to the grocery store.. organic foods go through the same shipping process as the conventional foods we eat.. so i feel organic is not so organic at all.. its basicly the same product just a different label put on the package to make more money.. and so rich people have something more expensive to buy at the grocery store.. haha .. thats just my opinion though...

  10. .. thats just my opinion though...

    I'm unsure what exactly you mean is just your opinion, but if you refer to whether "organic" foods are just labeled differently, then that is not just a matter of opinion. Or of "feeling."

    There are rules that have to be followed to be able to label your crops/meat as organic, and one those are that you don't spray with synthetic pesticides. As Rachel posits above, there might be some who use non-synthetic pesticides, but that does too make a big difference. These may or may not be good to ingest (I reserve comment until I actually learn more about this), but it makes a big difference for the environment whether you use stuff that's biodegradable or not (and natural compounds are).

    Besides, I know that it is possible (at least here in California) to buy crops that aren't sprayed in any way. I talk to local farmers at farmer's markets, and I actually used to work a little on an organic farm.


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