Organic food, conventional food

by NancyLebovitz1 min read14th Jun 201255 comments


Personal Blog

I've been wondering whether there's any solid evidence that organic food is healthier than conventionally produced food-- the arguments I've seen on the subject have been theoretical/aesthetic.

I'm interested in anything in the range from personal stories to scientific studies, but would prefer to avoid extremely general arguments or claims that people who prefer one or the other are demonstrating character defects.

Edited to add: Thanks for the replies. I'm hoping for experiments which test the effects of food produced in various ways on organisms, especially multi-cellular organisms. It was interesting to find out that plants which have to fight off insects for themselves have more mutagens.

The mutation experiment is very cute, but it leaves out the possibility of damage that isn't related to mutation-- for example, hormonal effects. Also, if it's done on a standard bacteria acquiring the ability to make a particular nutrient, this might not be a test for mutation in general.

I realize experiments on organic vs. conventional would be difficult, especially if you're tracking human health. It would be very hard to avoid confounding factors like other lifestyle factors and income.

"Conventional food" is actually a large blob of a concept-- different pesticides, fertilizers, etc. are used on different foods at different times, so finding out what people are actually exposed to would be difficult.

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All the reliable literature I have read says that:

a) Conventional produce and organic produce are nutritionally equivalent

b) Organic produce is more prone to rancidity as fewer preservatives are used

c) Organic produce will make you popular with people who wear glasses with no lenses

[-][anonymous]9y 5

Conventional produce and organic produce are nutritionally equivalent

Interesting! Can you link to the literature you've read?

You are misquoting the link. They say: "Is it more nutritious? The answer isn't yet clear."

They do they "The researchers concluded that organically and conventionally produced foodstuffs are comparable in their nutrient content.". That doesn't mean "Conventional produce and organic produce are nutritionally equivalent." If you add arsen to an apple you don't change it's nutrient content. An apple with arsen still isn't nutritionally equivalent to an apple without.

"C" is definitely true. I am convinced that, irrespective of the actual benefits of organic food, 80% of the people who buy it do so (largely) for signalling reasons.Half of the remainder probably do so accidentally and/or because it's the only item on the shelf at the time.

For what it's worth, I buy a fair amount of organic food, though this may be the first time I've talked about it. I'm definitely not signalling other people. I have a sketchy assumption that people mostly buy organic food out of a vague assumption that it's better/safer.

How would you tell why most people buy organic food?

I usually treat 'signaling' as the null hypothesis for human behavior: if the behavior doesn't make sense on its own, I assume it is signaling.

If a person is attempting to maximize their health, there are behaviors that have a better cost:effectiveness ratio than buying organic. Most of the people I encounter who buy organic do few to none of these things.

If a person is attempting to signal some sort of association with a the "health-food/green-living/upper-class" tribe (one or all of them) then buying organic makes far more sense.

Having encountered more of the signaling behavior than the healthy behavior anecdotally, the signaling behavior is more likely. I haven't invested any real effort into proving this (People could just be systematically acting in a sub-optimal fashion, for instance) but given how much of what people do is signaling behavior, it is my baseline explanation.

If a person is attempting to maximize their health, there are behaviors that have a better cost:effectiveness ratio than buying organic.

Um, are you considering convenience and other akrasic factors under "cost", and allowing for perceived or anticipated "effectiveness"? If not, your analysis is probably incorrect. (Heck, it's probably just incorrect when you consider what information people have about these behaviors.)

(People could just be systematically acting in a sub-optimal fashion, for instance) but given how much of what people do is signaling behavior, it is my baseline explanation.

You should probably update more of it towards the parenthesized hypothesis, i.e. people behaving in sub-optimal ways by default. If this weren't the default, there'd be little need for Less Wrong.

Having encountered more of the signaling behavior than the healthy behavior anecdotally, the signaling behavior is more likely.

Not only that, most of the actual 'health maximising' behavior that you have seen has probably been done for signalling too.

(Note to self: Find a way to convince yourself that looking like a health maximiser is cool.)

Easiest way is to hang out among other health maximization signalers, I suppose. Then all you have to do is convince yourself that status within your cohort is cool.

This may be one of the main benefits of going to a gym. I also know that one of the reasons having a "gym buddy" is recommended is because then you are more likely to exercise because if you don't then you are letting your buddy down. In fact, other than having someone to spot you, I suspect this is the primary benefit to having an exercise buddy.

I can also lift heavier weights for greater reps over more sets when I have a gym buddy. A combination of competitiveness and encouragement.

I usually treat 'signaling' as the null hypothesis for human behavior: if the behavior doesn't make sense on its own, I assume it is signaling.

That seems unwarranted. That you don't know why someone is doing something means only that you do not know the reason. I see no reason to think that when people say that organic produce is better than non-organic, that they are not merely saying what they actually think. If there was no-one who actually believed that, how could saying it be a signal?

There can only be such a thing as fake gold because there is such a thing as real gold.

I don't think there are many well known good health intervention that cost no resources besides money.

Exercising takes willpower. Buying organic food instead of the regular food takes no willpower.

I think that depends entirely on the relative availability and social status of buying organic. If buying organic food requires driving an hour and spending twice as much (which it can, if you live in a small town in the midwest or other similar situations) then it definitely takes willpower to buy organic. Similarly, if you have certain debilitating physical or psychological conditions, just buying food in general may take willpower (although the willpower cost between non-organic and organic may be negligible.) Also, just knowing that there are foods out there that you can't buy (given a pre-commitment to organic foods) can result in loss of willpower.

All things being equal, exercising probably takes more willpower than buying organic food, but there's nothing necessary about that in individual cases, and commiting to buying organic food probably uses some small amount of willpower, regardless.

[-][anonymous]9y 0

People could just be systematically acting in a sub-optimal fashion, for instance

Ways this could be the case:

  • they don't know about those other health-improving behaviours, or they misunderstand their effectiveness (or they believe they're effective but they lack the corresponding alief);
  • they weigh their costs more heavily than you do (my grandma feels that if she couldn't eat as much as she does, she would feel deprived of one of the main pleasures of life, whereas that would hardly bother me);
  • they correctly estimate their cost:effectiveness ratio, but they fail to adhere to them due to akrasia.

I'd guess that these effects are more relevant than signalling for a two-digit percentage of the people who buy organic food but don't do other health-benefitting behaviours.

The thing is, not eating organic food is also a way of showing affiliation.

[-][anonymous]9y 2

I think many more people eat non-organic food because it's cheaper and/or more easily available.

Even “many more” is an understatement. I think the fraction of people who would prefer non-organic food over organic food if the prices and the convenience were the same would be tiny.

Yes, because most people agree organic food is higher status and signals caring about high-status causes, even if they choose not to spend extra money on it.

Seems like conservation of expected evidence should apply here. Not eating organic food does have signaling implications, but it's so much more common that the signal should be a lot weaker.

This might not be true if you live in an area where organic produce is more common than average, though -- like a lot of middle-to-upper-class urban areas.

I probably should have thought this through more carefully-- there are people who think making a point of eating organic food is ridiculous, and talk about that opinion. At this point, I think they're into signalling territory, but that's about what they say more than about what they eat, I think.

Um. I suppose that some other food-eating behavior is also signaling, but I don't think that the majority if non-organic food eaters are doing it because they conceive of themselves as people who don't eat organic food and want to show off that fact. And I'm rather suspicious of the idea that not eating a selection of foods is signaling as a general rule. Like, someone could eat Italian food as a form of signaling (especially if they themselves identify as Italian) but someone who doesn't eat Italian food is probably not doing it because they think of themselves as someone who "doesn't eat Italian" and wants to signal that fact.

I suppose there are probably people out there who don't eat organic as a way of showing affiliation, but I don't think that encompasses any significant portion of those people who do not eat organic food.

Seconded all three. The health impact of the quality of a particular foodstuff (within the variance allowed by developed country regulations) is often overstated compared to the health impact of the overall composition of the calories you eat.

Doesn't (b) imply that grocery stores can't keep organic food on the shelf as long as conventional produce?

I don't think that applies to all products-- if the food doesn't contain oil or has been packaged in a way which prevents exposure to air, how can it go rancid? This is mere theory, however. Anyone have actual information?

I've been wondering whether there's any solid evidence that organic food is healthier than conventionally produced food

Shouldn't we equally be asking whether there's solid evidence that it's less healthy? It seems to me that if there's a substantial difference it could easily go either way.

(I eat a lot of organic food, but my main reason -- aside from whatever signalling nonsense the less-conscious bits of my brain may be inflicting on me -- is that I think organic is a not-totally-useless proxy for "produced by people who care about something other than profit margins" which in turn is a not-totally-useless proxy for "tastes better". And maybe also for "produced in ways with less adverse environmental impact" and, for meat, "prepared with more attention to animal welfare".)

I'm interested in your reasons for believing that people who grow food labelled "organic" care less about profit margin than people who grow food not so labelled.

Less exclusively, not less. And let me be more precise about what I (tentatively) believe: I am sure that all four quadrants of {organic, not organic} x {care only about max profit, care about other things too} are occupied; but I suspect that there is some correlation between being in the "organic" row and being in the "care about other things" column.

Why? Well, some of the reasons why people might choose to produce organic food rather than not-organic food are ones that involve caring about something other than profit margins. For instance, empirically it looks to me as if people who care about animal welfare are more likely to think that there's something icky about more-industrialized food production processes, and that people who think that are more likely to want to produce organically. (I make no comment on how rational it is for them to think that.) In general, people operating in a niche of any sort are (other things being equal) more likely to care about non-standard things.

(The following aren't exactly answers to your question but are other reasons for thinking that organically produced food may tend to be better. I am not very confident about any of them, and they are in rough decreasing order of how sure I am that the effect in question is real and goes in the direction I think it does.)

Producers of premium-ish products may be less likely to engage in practices that would look bad if they were disclosed, on the grounds that they are more dependent on customer goodwill, positive attitudes to their brand, etc., than if they were competing solely on price.

Organic food production is (I think) inevitably less efficient in various ways, which may mean that the relative benefit of any given cost-saving measure will be less for an organic producer than for a not-organic one, so that when there's a tradeoff between cost and quality choosing quality will be slightly more favourable on average for organic producers.

There are many cost-reducing measures available to food producers. All else being equal, such measures should be expected to reduce the quality of the food (perhaps not by much). Some of them are presumably not available to organic food producers. -- There's a possibly-equal and opposite pull in the other direction: There are many quality-increasing measures available to food producers, and presumably some of them are likewise unavailable to organic food producers. My hazy impression is that the things restricted by organic food production are mostly of the cost-reducing sort rather than the quality-improving sort, but that may well be wrong.

Cookery books by pretentious chefs fairly often advocate buying organically produced food. This gives two reasons for thinking organic might on average be better. Firstly, the chefs may know something about food. Secondly, people who read such books may (1) be more discerning about food quality, (2) tend to buy organic food and (3) be less price-sensitive than average, which might lead organic food producers to pay more attention to quality in order to keep their business.

These things were probably all more true in the earlier days of organic production, when it was more niche-y.

Well, I would say that there is a simple way to evaluate the taste aspect: do an experiment. My dad used to swear to me that brown-colored eggs taste better than white eggs. I was skeptical, so we did a little taste test. He couldn't tell the difference at all. Also, note that the most highly praised wines often do poorly in blind-taste tests against super-cheap wines from New Jersey.

Yup, but it's easier for some foods than for others. You can easily take two eggs, cook them exactly identically, and try them both side-by-side. Similarly for wines, which don't even require cooking. It's a bit harder with, say, a chicken for roasting. Even if you have an oven that'll take two chickens and don't have a spouse who'll object to roasting two when you only need one, it's far from trivial to avoid (say) overcooking one a little and undercooking the other a little, and that difference could easily swamp the subtler one you're looking for.

I'm not disagreeing that the question really ought to be answered empirically, but I'm not convinced it's so easy to do in practice.

Of course, what's hard for me with my small family and ordinary-sized kitchen may be easier for (e.g.) a restaurant or a consumer advocacy organization or whatever. I had a look on the web to see if anyone else has done this sort of testing. I found a small number of small-scale tests with inconclusive results. Enough to rule out "organically produced food is almost always much better", but I never believed that in the first place. (And enough to reduce my confidence in "organically produced food is a bit better on average", but not very much because of the low power of the tests.)

You want to buy organic food to give your money to organic producers, who are more likely to care about causes you also care about, and invest some of that money in those causes.

But it might be more efficient to buy the cheapest food of a given quality, which is not organic, and donate the remaining money yourself to those causes. Have you done an optimal philanthropy calculation?

Unless, of course, your goal really is to support people who support those causes, not the causes themselves. Which is also a reasonable and laudable goal.

If the opening paragraph ("You want") is intended to be descriptive of my goals, rather than merely addressing some hypothetical person, I'm afraid it doesn't describe them at all accurately.

I want to buy organically produced food (in so far as I do) not in order to get certain causes invested in, but in order to get better food. I don't think it's obvious that "the cheapest food of a given quality [] is not organic" (though I'm sure it's sometimes true) and in any case I don't have ready access to an accurate food-quality-ometer and have to rely on heuristics to some extent; preferring organically produced food is one such heuristic.

(Of course it might turn out to be a rotten heuristic. That's a separate issue.)

As far as optimal philanthropy goes, I'd be shocked if marginal improvements in the gastronomic life of middle-class Westerners came within three orders of magnitude of optimality for any reasonable person, no matter how efficiently pursued. Improving the welfare of the animals eaten by middle-class Westerners might do (it depends on the priority one gives to the welfare of non-human animals, and of course "philanthropy" would no longer be quite the right word) but indeed buying organically produced food seems like an inefficient way of pursuing that goal. Anyway, philanthropy has very little to do with my organic purchasing habits.

I see that both this [EDITED to add: I mean the parent of this very comment right here] and its grandparent have been downvoted. If that's because I'm being stupid then I would be grateful for some information that goes beyond "Someone didn't like this", so that I can try to repair my thinking (or improve my prose style, or whatever) as appropriate. Regrettably, even after rereading both it's not clear to me what the downvotes were for. Thanks!

My understanding is that many kind of pesticide and herbicide were proven to have adverse health effects, like cancer. But not all of them.

In the lack of information of which specific pesticide/herbicide/... was used on a given piece of "conventional food", and in-depth knowledge of the toxicity of each of them, I consider the "chose organic when possible" to be a reasonable safety measure. Some of the "conventional food" will not be any worse than the organic, some will be worse, and since I can't tell them apart, I consider "non-organic" to be weak evidence towards "slightly toxic".

The other point is, regardless of the effect of the food itself, some of the "conventional farming" does damages to the ecosystem - there is evidence it does pollute underground water, kill bees, ... Not all of it, but once again, I lack the ability to tell apart a "low-impact" conventional product from a "high impact" one, so I tend to chose organic also because of the effects not to me when I eat it, but to the everyone when it's produced.

Both of them are relatively weak reasons, but buying organic when possible only has a weak cost (it's not that much more expensive, and I can afford it).

That's the argument I've seen, and it's a heuristic I find plausible. It may even be that food is so complex that there's nothing better than heuristics. Still, I'm shocked that so little effort has gone into testing the health claims.

It's not easy to test the effects, because effects are usually long-term, things like cancer can take decades to be noticed, and "organic food" is quite recent. Remember how long it took to be sure smoking tobacco was really toxic. If I look at France (where I live), the "AB" label for organic food was created in 1985, and it's only recently (maybe a decade, even less) that AB food is available in normal supermarkets. So it's hard to have strong data yet on long-term effects. But I hope they'll come in the next decade.

i find that heuristic to be silly. Pesticides that are used in conventional farming are heavily regulated unlike ones used in organic foods.

Conventional produce is covered in a good deal of pesticides, the best way to remove them is peeling.

The link doesn't establish that pesticides are actually harmful, only that there's lots of them on conventional produce. However it is entertainingly written. :)

That's a shame, since the skin of fruit is often the best part - for flavor and health.

[-][anonymous]9y 2

That's what I usually say, but I mostly say it tongue-in-cheek -- the main reason I don't peel my fruit is that I can't be bothered to.

[-][anonymous]9y 0

Yeah, the nutritional profile of cucumbers or potatoes varies markedly by whether or not you consume them with skin intact...

Fascinating! Are there any rebuttals to the comments available? I'm particular interested in the replies to:

Synthetic insecticides may or may not be worse, part of the problem is that synthetic pesticides do not primarily work by mutagenesis like many natural ones to. They are neurotoxins (organophosphates, pyrethrins, DDT, carbamates), endocrine disruptors (juvenile hormones).

As I'm more concerned about neurotoxicity (if any) than carcinogens

[-][anonymous]9y 4

The claim is a bit misleading. Pyrethrin is in fact a natural pesticide, derived from chrysanthemums; the pyrethroids are semisynthetic derivatives of pyrethrin and work similarly. Phytoestrogens are a huge class of natural endocrine disruptors, although they are probably not nearly as potent or specific as the ones used for insect control.

It's also worth noting that insects have very different neurochemistry from vertebrates, and some of the neurotoxic pesticides affect receptors that vertebrates don't seem to have at all.

Of course, that's from the perspective of cancer, while we've been seeing worse things from other biological effects.

[-][anonymous]6y 2

It's difficult to determine the health impact of pesticides due to factors like long latency periods as described here. An absence of evidence for the harm of pesticides in fruits and veg isn't evidence of absence.

In the United States, pesticides costs several billion in public health, groundwater contamination, crop loss and pesticide resistance according to Wikipedia. I am interested in the intersection of cognitive epidemiology with agricultural pollution and diet in particular and pesticides cause cognitive dysfunction and contribute to Dementia and Parkinsons risk. What does this mean in terms of choosing to grow or eat organic produce?

Importantly, I have significant private knowledge of non-reporting of adverse effects from pesticides in agriculture in university's for studies sponsored by pesticide manufacturers and associations affiliated with pesticide manufacturers. THIS is my strongest reason for only eating produce with a skin I can peel, since I'm not confident in the process seperating organic from non organic produce or their availability.

Note, there are also studies indicating city pollution gives dog's a degree of brain damage. I'd stay away from cities too.

Although Wikipedia, (and I haven't searched google or research databases on this question), doesn't say insect repellant is harmful, I would hypothesise and assume from the mechanism of action that its terrible.

In fact, this worry is one of the only reasons I don't travel to those countries where one 'ought to wear' insect repellant constantly to avoid dengue fever and such, despite many attractions like altitude, culture, cheap cost of living, new langauge, new people and cheap hookers.

Spare a thought for the farmers. If pesticides became less dangerous, farming would be even less profitable. Rates of illness associated with pesticide and herbicide use in agricultural workers is obscene, but farming simply isn't a competitive business without non-'organic' pest and weed control, except in exceptional crop types/strains, highly biosecure regions, in very-pro organic markets, where there is minimal market access by competitive foreign exporters.

The other day I attended a seminar on market gardening in my state and got some notes. Doesn't seem like small scale farming is that sensible.

A new study just came out that seems relevant: Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize

From a press release:

The study involving 100 female rats and 100 male rats were split into groups and fed different amounts of either Roundup-resistant corn, Roundup herbicide or both, over two years. There was also a control group, which was fed regular corn a nd plain water.

Up to 50 per cent of males fed GM corn or Roundup and 70 per cent of females died prematurely, compared with only 30 per cent and 20 per cent in the control group, the study found. And overall, rats fed GM corn or Roundup developed two to three times more tumours.

Full text of the study can be found here:

Thank you very much!

This looks as though Monstanto's GMO corn could be very dangerous, but I'm not really qualified to judge the study-- for example, what if the strain of rats is unusually vulnerable?

Edited to add: Yeah, tumor-prone rats, and since the 200 rats were divided into 10 groups, small sample sizes. Still, the effects were pretty large.

Orac: The study is nonsensical.

Would other people here care to take a look at that study?

Also, I'm still concerned that lifespan (or even multigenerational) studies are so rare.

Thanks for posting the link to Orac. I didn't know he was still posting regularly there. I'm excited to read his dissection of the study when I have some spare time.

I'm also interested in any research on GMO's people have done.

Most of it is safe from my reading and it saves a ton of people

Right, I'm familiar with the latter portion. But this isn't a question about what is optimal on a large scale, only what is optimal for me eat. "Most of it" is worrying.

I have done a lot of reading, testing and visiting of farms for my own small farm. The promises of safe, healthy food at higher yields than conventional conventional farming sounds great.

I have researched 4 types of farming

  1. Classic conventional
  2. Modern Conventional
  3. Organic
  4. Permaculture

Unfortunately i will not be able to provide links to scientific studies or books at this time.

The differences between these 4 types are basically:

  1. : high crop yield, moderate to heavy use of synthetic pesticides, low crop rotation, high quality crop
  2. : Extremely high crop yield, low to moderate use of synthetic pesticides, high crop rotation, extremely high quality crop
  3. : Low crop yield, moderate to heavy use of classic pesticides, high crop rotation, low quality crop
  4. : Medium to high crop yeild, no use of pesticides, no crop rotation, medium quality crop

Because organic farming relies on classic pesticides the farmers are often forced to use dangerous types that are dangerous to humans and wildlife.

Because modern conventional farming has advanced techniques for choosing crop types and protecting them from pest they can get away with using very little synthetic pesticides. Unlike classic pesticides synthetic ones have to pass a lot of safety testing before they can be used. Rule of thumb: modern synthetic pesticides are safe

Finally due to the options modern conventional farming has, the crop will usually end up being better tasting, prettier to look at, bigger in size and cheaper to produce.

In the organic vs conventional discussion a lot of people fail to realize or mention that modern conventional farming is at a "space age level", near my home there is a tech research company that designs cutting edge farming machines. These things are basically huge robots that can run a farm almost on their own. Almost all of the farming here occurs in greenhouses that have full climate control with pests being naturally dealt with through the use of wasps and ladybugs, note that these are not organic farms.

Here is a pretty thorough discussion:

The authors do mention what was mentioned below, just because pesticides are not synthetic doesn't mean they are necessarily safer:

One such alternative is so called “natural pesticides” that are not synthetically produced, but are derived from nature such as botanicals pesticides (pyrethrum, limonene, and many others), microbial/biological agents (microbes, parasites) and inorganic minerals (boric acid, limestone, diatomaceous earth). These solutions are generally assumed to be less toxic for human health than synthetic pesticides and could represent an interesting alternative. But their usefulness is actually questionable because some such pesticides are not potent enough to control pests but at the same time do exhibit adverse effects for human health (i.e. “natural pyrethroids”).

Another study discusses how exposure to a chemical called Atrazine (ATZ) causes mitochondrial dysfunction & insulin resistance:

ATZ treatments led to weight gain

ATZ increased visceral fat and intracellular fat content

ATZ treatment worsened insulin levels and HOMA-IR values

ATZ induced insulin resistance

ATZ changed the ultrastructure of mitochondria

ATZ exposure decreased energy metabolism

ATZ impairs mitochondrial OXHPOS through direct action

ATZ treatment blocked the insulin-Akt signaling pathway