Sep 07 2010

Organic Food Quality

In my perfect world major societal decisions would be based upon logic and evidence, not ideology. But humans are ideological creatures – we develop belief systems that we jealously defend, and are subject to confirmation bias so that we falsely believe the evidence supports our ideology.

For example, I have never been a fan of organic farming. I have nothing specific against it, however it seems to me that the increasing popularity of organic farming is based largely on ideology (a naturalistic fallacy) than on evidence. I have no dog in that hunt, as they say – no vested interest in organic vs conventional farming at all. I really cannot think of a reason why I would care one way or the other – I simply want what works. Whatever farming methods are the most efficient and sustainable, producing the highest quality and cost-effective food – that’s what I support.

Organic farming is an odd mix of beliefs that are historically based upon the vague notion that “natural” is better. That does not mean that some good ideas have not emerged from the culture of organic farming, and I think if it has anything to offer it is a strong advocacy of sustainable farming. But when I listen to advocates, either personally or in a public forum, they seem to focus on a few specific claims that are rather dubious. I hear a lot about the evils of “big agro” and how organic farming supports small local farmers. However, if you buy organic at your supermarket you are likely buying from a “big agro” company that likes the higher profit margins of organic produce.

But the most common justification I hear for the higher price of organic food is that they are more nutritious. This is perhaps the one aspect of organic food that has the most evidence available to judge. The simple fact is there is no advantage to organic food vs convention food with regard to nutrition. One recent systematic review of published literature looking at nutrient content concluded:

On the basis of a systematic review of studies of satisfactory quality, there is no evidence of a difference in nutrient quality between organically and conventionally produced foodstuffs. The small differences in nutrient content detected are biologically plausible and mostly relate to differences in production methods.

Another recent systematic review, looking at health effects (rather than nutrient content) concluded:

From a systematic review of the currently available published literature, evidence is lacking for nutrition-related health effects that result from the consumption of organically produced foodstuffs.

So the best evidence we have to date indicates that organic food is neither more nutritious nor more healthful than conventionally grown food. Some people may support organic farming for other reasons, but the evidence does not support claims for nutritional or health superiority. I think the jury is still out regarding effects on the environment, and there is even evidence to suggest that organic farming may be worse for the environment.

But back to food quality – there is a recent study comparing organically grown to conventionally grown strawberries. This is a nice direct comparison. In the abstract the authors conclude:

Our findings show that the organic strawberry farms produced higher quality fruit and that their higher quality soils may have greater microbial functional capability and resilience to stress. These findings justify additional investigations aimed at detecting and quantifying such effects and their interactions.

The second claim seems non-controversial – organic farming methods cultivate a soil microbial system more than conventional methods. This finding is therefore no surprise, although it’s implications are unclear.

But I was struck by the first conclusion – that organic strawberries are “higher quality fruit”. Perhaps for some produce certain organic methods do have advantages – again, I will go wherever the evidence leads. But when I read the actual study I found that the data do not support the authors conclusions. You can look through the tables and decide for yourself how you would summarize the data, but in the body of the paper they report:

Leaf P (phosphorous) and fruit P and K (potassium) concentrations were significantly higher in conventionally grown strawberry plants than in organically grown plants; leaf Mg and fruit N (nitrogen) were also notably higher (P<0.10) in conventionally grown strawberry plants. All other strawberry and leaf nutrient concentrations were similar.

And elsewhere they note:

Organic strawberries had significantly higher total antioxidant activity (8.5% more), ascorbic acid (9.7% more), and total phenolics (10.5% more) than conventional berries, but significantly less phosphorus (13.6% less) and potassium (9.1% less).

So – the conventionally grown strawberries had some advantages, while organic strawberries had others, and otherwise the nutrient content was the same. How does that make organic strawberries superior? You get slightly more of a couple vitamins with organic strawberries, and slightly more minerals with conventional strawberries.  This seems like no significant difference to me.

You also have to consider that they were comparing multiple varieties of organic and conventional strawberries and making multiple comparisons. This looks like a scatter shot of random results from looking at tons of comparisons. There was no consistent pattern of superiority to any variety studied. Again – look through the tables and see for yourself.

They also found that organic strawberries were smaller (not surprising), which also means they were denser and redder. With one variety subjects rated the organic strawberries as more appealing, with another no difference, and with a third they rated the conventional strawberries better. Again – seems like a wash to me, but the authors emphasize that in one variety the organics were rated higher.


I remain unconvinced that there is any advantage to organic farming. This study, if anything, supports the conclusion that there is no significant difference. Organic produce tends to be smaller and denser, and may have slightly higher concentrations of some vitamins (but not significant in terms of nutrition and health), while conventional produce has higher nitrogen and certain minerals. This makes sense based upon the methods of fertilizer used, and is consistent with previous studies. Bottom line – these are minor differences with no real impact on health and nutrition.

But the bigger issue is that organic farming is an eclectic collection of methods grouped together for purely ideological reasons (based largely on the naturalistic fallacy). In my opinion it would be better to judge each farming method on its own merits, based upon the best evidence available.


104 responses so far

104 Responses to “Organic Food Quality”

  1. Sprawnon 07 Sep 2010 at 8:55 am

    The organic food problem illustrates several uncomfortable issues to me. First, the willingness of most people to believe a story over data. Second, the near inability of people to make sense of data when it is present. Third, how people will pay more for a good feeling.

    When I see the “Organic” label, I am unmoved. I have no way to verify it (someone would have to talk to a lot of farmers, sorters, pickers, and so on to verify such a thing), but I would not be surprised to hear that so-called “organic” foods are merely the best-looking conventionally grown produce, picked out of the line and handled more gently throughout the whole transportation and display process. How could anyone tell the difference? And if the trucks arrive and the crates say “Organic” on them how would anyone ever know? There is simply no way of knowing.

    I am certain that there are “Organic” farmers out there, conscientiously trying to improve the means of producing our food, hoping that there methods will be more sustainable, and their output will be nutritionally superior. But these conscientious growers are not in a vacuum. They are in direct competition with other organizations where it is not only difficult but well-nigh impossible to track produce from the fields to the display case. With the price markup for the organic label who would ever know?

    The incentive is there for “accidental” mislabeling. And it is totally and completely untrackable.

  2. einnivon 07 Sep 2010 at 9:00 am

    As someone who worked in a microbiology lab of an Agronomy dept in college, I always assumed the organic farming thing was more about land/environment management than health. Even this is far from clear but it does appear that organic, low-till farming might be even better, in some situations, than no-till for building healthy soils (see are of course also issues with fertilizer and pesticide. Not on the food itself, but as runoff in to the environment. Fertilizer is actually a bigger problem in that area than pesticide (most people assume the opposite).

    There are also economic and political issues which may depend on one’s values. Improving low input and traditional techniques (such as crop rotation) may benefit developing world farmers the most. Is it better to support high input farming that requires a large supply of capital in developing countries? Well it depends on what you want. High input farming usually results in people being forced off their land where they may not be living the high life but at least they can support themselves and have a rural support network. They end up in , often disease ridden, slums fighting for factory jobs with everyone else that got pushed off their land. To me it isn’t really worth it. Human dignity may not be easy to put a price tag on but it is worth something imo.

    But ,yeah, it doesn’t surprise me there aren’t really any health effects. NPK is NPK is NPK. Unless there were significant trace nutrient differences we shouldn’t expect to see much difference there.

  3. John Ellison 07 Sep 2010 at 9:41 am

    FYI there was another review of organic food health claims recently. It also tracks the crappy media reporting and dubious claims of organic advocates.

  4. Brian the Coyoteon 07 Sep 2010 at 10:30 am

    I think that as recently as there may have been a difference in organic produce but not for the reasons that organic advocates may believe.

    I come from a farming background going several generations back. When you live in a farming community it becomes clear that there all farmers are not created equal. Some are better than others, usually because they care more than others. My family’s farm was never an organic farm but we used far less herbicides, pesticides and fertilizers than most and still had better crop yields. The difference was that this was a family farm with generational knowledge of the land and it could be micro-managed to get the best crops. My late grandfather is almost a legend for pulling off good wheat crops even in bad years.

    So when becoming an organic farm first became a business option I think many of the first farmers attrracted to it were the good farmers who had a grasp of the husbandry of the land and simply carried those good practices to their organic operations.

    When organic farming became just another big agri-business all of that, for better or worse, was lost.

    All emotions and nostalgia aside, Steve is right. With 7-plus Billion people to feed agriculture needs to be about getting the most from limited resources. “Organic” has become just another statement of conspicuous consumption.

  5. Alain Miville de Cheneon 07 Sep 2010 at 10:39 am

    Modern agriculture has a host of undesirable consequences.

    Dead zones in the sea are produced by fertilizer runoff.
    Nitrates pollute groundwater.
    Fertile soils are impoverished by erosion and the collapse of their biological structure. Their function as CO2 sinks is greatly reduced.
    Mono-culture of a few varieties of plant species leaves us open to sudden devastating destruction by pests and fungus (
    By promoting the use of GM seeds, it is removing the possibility of farmers being allowed to reseed their fields from last year’s crop.
    It is highly dependent on petroleum for its fertilizers, herbicides, and pesticides.

    Large scale organic agriculture can obviate these consequences while producing as much or more per hectare. It can actually rebuild degraded lands.

    Things are as they are not necessarily because they are the best way possible, but because there are large vested interests which will do all they can to keep things running their way. This is the way of the world. The system we have produces a lot of food but come with a lot of problems. It needs transformation to become more benign and especially sustainable.

    Organic produce is almost indistinguishable from non-organic as far as looks, taste, and contents goes. Organics are better for the planet and people as a system of production.

  6. aquademiaon 07 Sep 2010 at 10:42 am

    I understand the natural fallacy perfectly, and I am unmoved by claims that there is no evidence that organic food is better. The emphasis should be on “there is no evidence” — not yet. I buy organic food for what it doesn’t contain — pesticides — as well as for its sustainability.

  7. mufion 07 Sep 2010 at 11:15 am

    OK, two post attempts later, testing…

  8. mufion 07 Sep 2010 at 11:26 am

    Well said, eiinniv.

    To paraphrase philosopher Daniel Dennett: If you make youself really small, you can externalize virtually everything.

    Although he originally made that statement with respect to the subject of free will (which comes up here on occasion),

    it seems to apply just as well to how one looks at agriculture, which leads me to my next comment…

  9. superdaveon 07 Sep 2010 at 11:32 am

    Some non organic food has fewer pesticides than some organic foods. Aside from that, I find the experience of farmers markets that typically sell organic food more pleasant and fun than the supermarket but other than that see no real advantage.

  10. David in NYCon 07 Sep 2010 at 11:41 am

    I can’t believe there’s no mention of pesticides in the article, and only one mention in the comments.

    I buy organic when I can, and I have never once thought that the fruit or vegetables themselves are more nutritious.

    I’ve bought because I support local farmers, because I know in most cases the methods of production and distribution are more environmentally sound, and because I don’t want to eat all the crap that the big companies put in their food to ensure that the crops are big and bountiful and beautiful to look at.

    How many studies need to come out that show that additives to foods are bad for us? And, the religious view of SCIENCE is getting in the way, because it is impossible for one study to replicate the deleterious effects. It takes years of accumulation of these additives, plus other stressors on our system from our polluted environment to result in damage.

  11. mufion 07 Sep 2010 at 11:41 am

    OK, WordPress is giving me grief again. I’ll give this one more try:

    The article linked above only supports the conclusion that “organic farming may be worse for the environment” (as Dr. Novella put it) if one externalizes all of the factors ignored in the study (e.g. biodiversity, improved landscape, animal welfare, soil condition, and water use – not to mention all of the foods that didn’t make the “pitfalls” list, which might fare better). Forgive me if I am unwilling to do so.

    Even the Wikipedia entry on organic farming seems to give a more comprehensive review, or at least works as a starting point to supplementary studies. It also provides some grounds for skepticism of (ideologically or commercially motivated) claims of having “debunked” organic methods.

    Hey, I don’t mind if some folks react with a warm fuzzy feeling to conventional methods. I only mind when they act like anyone who reacts that way to organic methods is less rational than they are.

  12. Ufoon 07 Sep 2010 at 11:49 am

    Here’s a link to a podcast with the guys who made the strawberry study:

    The interviewer is giving them a lot of slack I think, and they still come across as dodging some important issues. Anyways, everything is worth looking into.


  13. RichWilsonon 07 Sep 2010 at 11:50 am

    I’m not sure about other countries, or what country you’re in, but in the US there are several Organic accreditation agencies, including the USDA. It does mean I have to trust the agency that is vouching for the farmer and the supply chain, but I can’t go out and interview the original source for anything else in life. The downside is that getting certified can be expensive. When someone at the local farmer’s market tells me their stuff is organic, they just can’t afford all the paperwork, I really have nothing but their word.

    All that said, I’m less concerned with the quality of the actual food, and more with the environmental impact. e.g. Methyl Bromide and Methyl Iodide in strawberry production, antibiotics not for bacterial control but for growth in livestock.

  14. davewon 07 Sep 2010 at 12:11 pm

    I think there is goal-post shifting happening on both sides of the argument. As Steve and a number of commenters add to is there are potentially many advantages to organic farming. In order to say whether it is better you first have to define what you mean by “organic” and then define what you mean by “better”.

    My notion of organic aligns with Rodale’s idea which is usually called “sustainable” in today’s parlance. The article hints that the style of organic farming is more sustainable. I know some more research is being done in this area and I eagerly wait the results.

    I know the stuff I grow and the farmer down the street grows fit the best definition of sustainable I have been able to come up with so this is mostly what I eat. In the megamart I’ll generally buy organic produce so I don’t have to think about pesticide residue. Whether a box of crackers is labeled organic or not I really couldn’t care.

  15. Steven Novellaon 07 Sep 2010 at 12:19 pm

    This article was not about pesticides or about sustainability or the environment. I was about food quality (just like the title says) – so forgive me if it is not a comprehensive treaty on all things organic.

    I made a side comment about the environment to make a simple point – this remains controversial. It cannot be taken for granted that organic farming is better for the environment.

    And I will emphasize, there is a problem with using the very concept of “organic” farming as if it is one thing – it is a collection of methods, some may be good while others are bad or neutral. It’s about marketing and ideology.

    Regarding pesticides – organic farming uses pesticides. They just use “natural” pesticides – but there is no reason to think they are any safer. They generally require higher or more frequent dosing, and may in fact be worse for the environment. They are not as well studied, based upon the false assurance that they are “natural.” They are a perfect example of substituting actual evidence with a warm and fuzzy ideology. Don’t look too carefully at the actual evidence – it’s all “natural.”

    But that is a topic for a separate blog entry – too much for one comment.

  16. sonicon 07 Sep 2010 at 12:37 pm

    I use organic methods in my garden- the soil has gone from hardpan to very loose and rich.
    It was the conventional methods that took the soil from rich to hardpan.
    The big farms in my area seem to have problems with the soils (salt, lose of fertility) and this is what makes the interest in new farming methods.
    Besides, I can walk around in my yard without having to wear a gas mask.

  17. colluvialon 07 Sep 2010 at 12:57 pm

    While organic farming may encompass practices that preserve/enhance soil quality, minimize ecological impacts, and produce healthier plants, in some cases it may exhibit none of those things. The emphasis should be on practices and not on particular ingredients. Besides economically producing a crop, the important considerations are:

    Does it keep erosion at an acceptable (sustainable) level?
    Does it preserve soil quality by maintaining adequate levels of organic matter and nutrients?
    Does it limit nutrient loss to surface and ground water to levels that won’t cause undesirable changes (eutrophication) of nearby bodies of water?
    Does it use pesticides in ways that won’t harm humans and other species that are not the target?
    Does it support a landscape with species other than the main crop so that it’s not otherwise a biological wasteland?

  18. bleroyon 07 Sep 2010 at 1:22 pm

    Seems to me there are three possible reasons to choose so called organic food:
    Environmental impact, nutritional value/health impact and taste. While the post does an excellent job refuting the first two, the third one probably deserves and has been the subject of studies. Any pointers on that?

    +1 on pushing the debate to sustainable agriculture.

  19. stompsfrogson 07 Sep 2010 at 1:47 pm

    @ davew: Does “crackerizing” wheat make the pesticide residue go away?

    Stonyfield, the organic yogurt company, gets strawberries from China, apple puree from Turkey, blueberries from Canada, and bananas from Ecuador. And they’re looking at importing milk powder from New Zealand next. See, they had to expand after they were sold to Danone, the $17 billion French company.

    There’s some sustainable food right there.

    China: known for quality, not fake stuff, right? They still manufacture DDT there. They paint hills green for international TV cameras. And that’s where your “organic” food is coming from, because organic demand is way outstripping supply, because conventional farming produces more food and the USDA guidelines for the “organic” labeling are extremely lax. The No. 1 producer of organic milk in the US, Horizon Organic Dairy, has 8,000 cows in the Idaho desert. They constantly pump water to grow grass so that their livestock can have “access to pasture.” That’s all you need to technically be USDA organic. They don’t care how much access. Their livestock eat mainly feed, grazing is not the majority of their diet. Feed grown – get this – conventionally. The USDA has a list of exceptions you can include in your “organic” food, all you have to do is claim that an organic version is not available in the quality or quantity needed. Because really, where does one get organic fructooligosaccharides?

    /rant. sry :D

  20. John2on 07 Sep 2010 at 1:53 pm

    Unsurprisingly we get people saying that it’s not really about the nutrition (which, strangely, was not the story before the data was in…), others saying that its about pesticides (as mentioned by Dr Novella, organic farming is allowed pesticides, too, just not the modern ones that break down so well and so can actually increase the damage that they do), and others giving us the sort of anecdotes that we’d all scoff at if they were from an advocate of alternative medicine “I took ginseng, and my soil improved, It was not eating ginseng that made my soil hard”.

    For some reason, otherwise rational people still manage to have their woo sacred cows, and organic produce is a common one.

    Sonic, you did not need to wear a gas mask around your garden before. Many of us grew up in the heyday of pesticides, herbicides, additives, preservatives, and all sorts of bizarre colourings in our food, without gas masks, and we were not all dying en mass from these exposures.

  21. Steven Novellaon 07 Sep 2010 at 1:58 pm

    Regarding taste – no evidence for an advantage there either:

    But there are too few well-designed studies to say anything conclusive.

    We are still left with organics being marketed with claims for specific advantages that are not based upon solid science.

  22. daedalus2uon 07 Sep 2010 at 2:17 pm

    Plants only absorb inorganic nutrients. Organic sources of nutrients must be mineralized by bacteria (converted to non-organic compounds) before they can be absorbed and utilized by the plant.

    The regulations of what constitutes “organic” fertilizers are not consistent. Any type of manure is considered acceptable as an “organic” fertilizer, even from non-organic sources. A great many chicken producers (chickens for meat, not eggs) put arsenic in the feed. Chicken manure from such chickens has ~10 to 20 ppm arsenic and yet is still considered “organic” because it came out of a chicken. Why is manure from conventionally fed chicken considered “organic” when the eggs and meat of those chickens is not?

    Some suppliers of chicken manure go to great lengths to show that they have a certificate that says they are “organic” but don’t post a chemical analysis of their product. Some places do require fertilizers to be assayed for heavy metals and some fertilizer containing chicken manure has warnings to not use more than a certain amount per area of land. They don’t say why, but the reason is to not exceed the allowed arsenic loading.

    Organic farming is not the same as sustainable farming. Growing and harvesting crops removes bulk and trace nutrients from the soil. If those bulk and trace nutrients are not replaced, the soil will become depleted. Organic farming only allows organic sources of nutrients. If a particular soil is depleted in a single trace nutrient (zinc for example), why not just add zinc? Why add only “organic” fertilizers containing many other things which the soil is not deficient in? All that does is add cost and potential for excesses and runoff. To deliver a few pounds of zinc, why supply many tons of manure at increased cost, increased compaction of the ground and increased CO2 emissions for transport and as the manure is oxidized by soil bacteria?

    There is not enough organic fertilizer to supply the world’s soils with the nutrients that are being harvested from them. This is why manure from conventionally farmed animals, even animals that are given toxic compounds like arsenic is considered “organic”. If only manure from “organic” animals was considered to be organic fertilizer, there would not be enough and “organic” yields would plummet.

    Some nutrients like potassium are highly soluble and so leach and flow to the sea where potassium chloride is recovered by solar evaporation to make the chemical fertilizer muriate of potash. Why is muriate of potash from urine considered to be “organic” but muriate of potash from sea water is non-organic? It is the naturalistic fallacy.

  23. Calli Arcaleon 07 Sep 2010 at 2:28 pm

    What it comes down to is that there are individual practices that are probably more efficient and more sustainable — but they are not limited to organic farming. (Note that the term “organic”, as applied to produce sold in the US, has nothing to do with tillage or quantity of pesticides or acreage or crop rotation. It’s about what sorts of pesticides and fertilizers you use.) I think applying a buzzword is foolish, because it creates a pointless dichotomy, and because it fails to reward farmers who farm sustainably but use chemical fertilizers while rewarding farmers who farm irresponsibly but use organic fertilizers. (Yes, it is possible to farm irresponsibly and get the “organic” label.)

    There’s a bigger problem behind it, though: the strong but fairly ridiculous belief that there is only one best way to farm. Though the buyers of organic produce (as a whole, not individually) seem to think that the best way is to farm organically, that isn’t universally true. In fact, this idea of one correct farming method comes from conventional farming, and it’s not good. It seemed good in the mid-20th century when so much focus was on standardization, but farming is one area where we need to be more cautious about standardizing. Some methods, some breeds, etc are better suited to some areas and situations than others. Why do California dairies have largely the same cattle as Wisconsin dairies? It’s a very different climate. And then there’s the sudden fashion for Angus beef. Why? Is it really so much superior that ranchers should switch their herds entirely over to Black Angus? The loss of “heirloom” breeds of livestock and plants should be more concerning to the general public than they currently are. The loss of genetic diversity is more than just a bit of nostalgia; we lose flexibility in the face of looming climate change.

    There isn’t a “best” way to farm, and we should probably be cultivating a range of methods rather than obsessively focusing on a single method. And we shouldn’t have silly boxes for “organic” and “conventional”.

    Me, I like farmer’s markets. The produce usually happens to be organic, but that doesn’t really concern me. I’m more interested in supporting the hard-working people who grow it, and it’s neat getting to talk to them. It’s not some huge agri-giant hiring people of dubious legality who will have little recourse if the company treats them poorly. And it’s fun! The farmer’s market is open-air, and it’s almost got a carnival atmosphere. A lot more colorful than the supermarket, with artisans selling all sorts of things I probably wouldn’t have looked for and certainly would not have seen at Target.

    One product where I have noticed a difference is eggs. Not because of the organic part, or even the “no antibiotics” thing. Truly free-range hens eat bugs and stuff, and on a small farm, they probably also get table scraps. (My in-law’s hens do.) The more varied diet does affect the eggs, and I like the difference. The yolks are noticably darker in color, and richer in flavor. (Note, however, that I can only tell the difference if it’s plain eggs. If they’re mixed with anything else, like cheese or chocolate, that flavor difference is completely overpowered.)

  24. JasonEllison 07 Sep 2010 at 2:36 pm

    What about the recent study regarding ADHD and urinary concentrations of dialkyl phosphate metabolites of organophosphates in children?

    Wouldn’t this generally make the consumption of organics better without qualifying the notion that the composition of organics themselves is intrinsically superier to ‘GM’ foods?

    I’m not a current consumer of organics, but I am a Dad and naturally (no pun intended) concerned.

  25. Steven Novellaon 07 Sep 2010 at 2:58 pm

    The evidence for a link is preliminary, but let’s assume it’s real (a big assumption, but not crazy).

    You can minimize exposure by simply washing your produce. That is proven to dramatically reduce pesticide residue.

    Also – it may be that organophosphate pesticides need to be regulated differently.

    And further – we do not have good information on the safety of many organic pesticides.

    Calli got it right – “organic” vs “conventional” is a counterproductive false dichotomy. Each pesticide should be judged on its own merits by the evidence, and regulated accordingly.

  26. stompsfrogson 07 Sep 2010 at 3:15 pm

    “Americans eat about 1,500 mg of natural pesticides per person per day, which is about 10,000 times more than the 0.09 mg they consume of synthetic pesticide residues.”

    Reminds me of thimerosal.

  27. DEG80on 07 Sep 2010 at 3:22 pm

    I hesitate to post this because it borders on anecdotal given that I have no access to the data and the results were never intended to be published, but on the pesticide issue:

    I taught Instrumental Analysis at Berkeley twice (I’m a grad student in chemistry). One of the labs we had the students do was to test for pesticides on produce. The students were responsible to choose whatever produce they wanted from whatever source they wanted. Both semesters some students found conventional pesticides on supposedly organic produce from Berkeley Bowl ( How it got there is anyone’s guess (two of my guesses: perhaps it wasn’t really organic produce or perhaps it was stocked on a shelf that had previously held conventionally grown produce that left pesticides on said shelf).

    The second part of the lab was testing for how to get rid of the pesticides. Most students found that washing with water was sufficient to remove the bulk of the pesticides present on produce. Washing with slightly soapy water removed all detectable traces of pesticides.

    So, I wouldn’t trust that organic produce is pesticide free. Wash your food, preferably with slightly soapy water.

  28. Eternally Learningon 07 Sep 2010 at 3:26 pm

    I’m by no means an expert in organic food/farming so I’ll not pretend otherwise, but several people I’ve known very well have made choices to use it primarily as opposed to conventionally produced food and have relayed the reasons for their choices to me. I’ve never really heard the nutrition arguments, but primarily the reasons given were pesticide use, supporting local/smaller businesses, and better taste. Also, though this obviously does not apply to this article’s point, the organic meat industry tends to be far more important to the people I know than the fruits and vegetables. The main reason behind this is the treatment of the animals and the lack of hormone injections and such.

    Please keep in mind, I’m not making any statements about the methods used in organic or non-organic farms. I’m merely stating the opinions expressed to me by others as to why they choose organic. Personally, I find the arguments for the meat industry (assuming they aren’t based on bad data of course) far more compelling than the ones for crop farms.

  29. Paideumaon 07 Sep 2010 at 3:32 pm

    I too remain unconvinced of the merits of organic farming.

    I have a friend who is very much an advocate who has chatted about this with me from time to time. Like me, he thinks the taste and health justifications are probably fictitious; however, he is very concerned about closing off the biodiversity. He feels that decreasing the biodiversity of a food crop is dangerous since it increases the damage done by any infectious agent that takes hold. He cites near-extinction of the once-popular Gros Michel banana variety and the current problem facing the Cavendish variety.

    While I’m not a geneticist, it seems to me that he may have a point, but then, as you say, to reify “maintaining a biologically diverse crop” as “organic farming” is fallacious.

  30. Steven Novellaon 07 Sep 2010 at 3:39 pm

    from the reference I linked to above regarding taste:

    “Consumer panelists in both tests considered organic produce to be healthier (72%) and more environmentally friendly (51%) than conventional produce, while 28% considered organic produce to have better taste.”

    I don’t know how the question was phrased, but it is likely that these numbers reflect reasons for buying organic, not just belief about organic.

    #1 is that organic food is healthier, and this is not supported by evidence, in fact 50 years of research shows otherwise.

  31. wallet55on 07 Sep 2010 at 3:48 pm

    Amazing, Science Friday on NPR did a piece on this and gave