Doctor's Note

For more on pesticide residues on produce, see my recent video Are Organic Foods Safer? For how to best get them off, see How to Make Your Own Fruit and Vegetable Wash. Pesticides are one thing, but Are Organic Foods More Nutritious?

That was the first in my five-part video series on organic foods, which ends tomorrow with the wrap-up: Are the Benefits of Organic Food Underrated or Overrated?

For more on the impact of food contaminants during pregnancy, see:

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  • Adrien

    “Insects eating insecticides don’t do well.” Hmmm, maybe that’s why the bee are gone now.

    • Matthew

      I’ve got plenty of bees: bumblebees, carpenter bees. Come over and take as many as you want.

      • MarthaLA

        You are fortunate! I have some carpenter bees and bumblebees, too, but not plenty, not much activity.

      • joeboosauce

        Is it true that the queen bees wings are clipped? If so, that would be really cruel and inhumane.

        • Bill W

          No!! Read about the bees as they are very interesting. She flies out one time and a drone impregnates her, then it is to answer natures call and lay eggs until the hive gets overpopulated or she becomes too old. The few drones are the only males and every fall they are killed then, in the spring, the hive produces new drones.

  • elsie blanche

    Eating grapefruit makes certain drugs stick around in body circulation for longer than they should, right? Well, I’m wondering
    if eating grapefruit while having a lot of conventional (not organic) produce in the diet would possibly cause the “drugs”/Chemicals in conventional produce to linger in the body for longer than is safe? A theory of mine, but it makes a bit of sense as I see a lot of these chemicals (pesticides) as drugs. And they have lots of warnings out alerting folks to be mindful of not eating grapefruit while taking certain medications because it delays the liver’s response time in eliminating these drugs from the body.

    • Joseph Gonzales R.D.

      Hi Elsie. Grapefruit can have drug-nutrient interactions absolutely. The thing is I’m not sure if they would affect pesticides and turn them toxic in the same way some medications can do.

  • Plantstrongdoc M.D.

    Simply put: I like the thought of eating and serving food for my friends and family – one exception: My mother in law – that contain as little poison as possible and I like the thought of food grown without filling nature with pesticides. And of course I am totally non – GMO

    • Mark G

      News sources reported yesterday that Chipotle, Panera and a few other food companies have pledged to take out as many fake and unnecessary additives as possible. Panera found over 150 additives that they questioned, most of which they’ve decided to remove. Some commentators I heard–I think on NPR–said that it’s things like titanium dioxide added to mozzarella cheese to make it whiter. They observed that it it toxic, but that dose makes the poison and so that little amount won’t hurt you so it’s not much of a change. First, how do they know it’s not a problem? Second, they fail to consider the cumulative and synergistic affects of all this crap together on a person’s health. And third, they failed to consider the cumulative affect that the tons of this stuff used on mass scale has on the environment and the general micro-biomes. Instead of looking for ways to support better decisions, you get reporters thinking they are helping by down-playing problems so as not to scare people.

      • Mark G

        I found the story. It was on PBS News Hour. Well meaning commentators, giving a simplified, erroneous assessment of the opportunity.

      • Plantstrongdoc M.D.

        “cumulative and synergistic affects of all this crap together on a person’s health. And third, they failed to consider the cumulative affect that the tons of this stuff used on mass scale has on the environment and the general micro-biomes” – You are absolutely right!
        Heard a scientist the other day calling our oceans “plastic-soup” due to all the crap and especially plastic filling up our oceans.

      • baggman744

        I’m a little more optimistic. Consumer demand is no doubt gaining momentum in driving the “healthier food” movement. Without getting into the whole “vote with your forks” debate, we’ve just begun. The private sector is far more flexible than government in responding to our demands because they’re after one thing, profit. But its up to us to keep the pressure on. Our voices are cumulative. I regularly e-mail and/or call food companies, as well as my local super markets giving my opinions, requesting better choices, inquiring about ingredients, chemicals, pesticides, requesting GMO free, etc. Although not quite fast enough, they’re listening, and making improvements.

        • mbglife

          I agree that the public is causing this change and that it’s a good thing. My point was that the commentators were out of touch.
          -Mark G

  • Mark G

    Seeing the photo of the no pesticides sign on the tomatoes reminds me of a confusion I had early on. While walking through the farmers markets I would ask, is this organic and to a person, the person, the response I got at every stall was, a very cheery, “no pesticides”, in a tone that suggested an affirmative reply. But then it dawned on me that no one was just saying yes or no, so the next few times I got this response I countered back, “ok, but is it organic?” Sometimes this went back and forth a bit but then to a person the ultimate response was, no, it’s not organic. It was just that sampling x% of the group had shown no pesticide residue. I think it’s up to everyone to decide for themselves if that level is acceptable to them, but it should be based on full awareness of what you think you’re getting.

    • fencepost

      There is more to organic growing than just avoiding synthetic pesticides. Fertilizer use, for example, is also covered by the organic rules. Also, the organic rules permit pesticides that are naturally occurring and some of those are things you do not want to eat. There are also some crops that can generally be grown without pesticides. In my area, tomatoes only have two common pests: the hornworm caterpillar which can be picked off manually, and Late Blight which needs fungicide sprays for prevention (there is an organic fungicide by the way).

      Farmers who sell at farmers markets quickly learn what they have to say to have happy customers. Some farmers are more flexible than others when it comes to interpreting the organic rules or defining ‘pesticides’. Very few customers know enough about organic growing methods to ask the right questions to learn what is really being done.

    • b00mer

      I’m not an expert in this area, but I’ve heard that obtaining usda organic certification can be time consuming and costly, and the smaller the farm, the more this cost is felt. Some small farmers may follow all the organic rules but aren’t certified and thus can’t legally call their products organic. Many of these small farmers may altogether have better, more holistic practices that are more in line with organic philosophy than some of the huge certified organic farms. So I agree it’s best to really talk with the farmers to see what their practices are, but keep in mind the “organic” label may not be the most relevant criterion to judge by.

  • David Johnson

    A minor point perhaps but I think it unfortunate that the introductory picture shows a “pesticide free” sign since many people wrongly think organic means pesticide free. I have strong doubts that (supposedly) organic food from, say, Mexico is really better than locally grown nonorganic food, and in fact will pick USA produced nonorganic food over imported organic food, depending on the country of origin and my general trust in the country. I am wondering if there are studies measuring the pesticide type and residue on imported organic food by country of origin.

    • Mark G

      I don’t have a link, but I do recall that one or more environmental watch dog groups had lists several years ago that showed the relative levels of pesticides in different foods from different countries. It found that Mexico, latin american, and europe all use less pesticides than their counterparts here in the US on the same crops. They had charts showing the comparative levels. You might try some google searches. I bet you’d find some of the charts. It was enough to convince me it was fine to buy foreign crops. When I visited relatives in France last year they were explaining their farming laws, all of which seem much more protective of human health than the ones I’ve heard about here. I’m far from being an expert, but I offer my experience as one data point.

  • Jason Huang

    I definitely go with organic food. In USA, pesticide, glyphosate, is present in almost every non-organic food. Glyphosate preferentially kills the beneficial bacteria in human’s gut, leaving pathogens to overgrow. Glyphosate disrupts CYP450 enzymes and depletes aromatic amino acids and important minerals such as calcium, manganese, zinc, cobalt, iron, etc. Glyphosate is found 60-100% of the air samples, the rain samples and the surface water samples. It is found in the blood of pregnant women and in the unborn fetuses.

    • Julie

      Good point! Glyphosate (in RoundUp) is way more toxic than Monsanto has lead us to believe, implicated in many diseases such as ADHD and cancer. As soon as I learned about glyphosate being used as a desiccant on almost everything, I immediately switched to organic beans and grains.

    • Joseph Gonzales R.D.

      Nice post, Jason! I am sure you know, but Dr. Greger also shares some research on glyphosate if anyone following this thread is interested. Thanks!

    • Wilma Laura Wiggins

      And apparently the farmers have been convinced that “heath nuts” are misinformed, ignorant and don’t realize that glyphosate is safe. They really need to be educated by other than Monsanto. From what you are saying, it sounds like it is everywhere and even eating organic will not eliminate it, but cut it down at least.

  • kaibloom

    My opinion of organic food in UK and why I buy it is based on the observance that it is more than what goes on my plate. One aspect of this is to say that it is generally accepted there is more wildlife around organic fields than those sprayed with chemicals. In this instance I see a value to buying organic food above and beyond my own diet. While I accept from the recent videos from Dr Greger showing “whether the evidence to support organic fruit & veg is actually better in a nutritional sense, safer or healthier, is rare if not unavailable”, I say that observation of the countryside, the life present around organic fields shows better health and is an indication, a guide, as to what I prefer to eat.

    • Julie

      Absolutely. Here in the US the sprayed fields are mono-crop deserts with no life whatsoever. The organic fields, on the other hand, are alive and provide an important ecosystem for all kinds of wildlife. Really good point, kaibloom–the positive impact of organically grown food on environmental health is huge!

    • fred

      Here in the US midwest…corn/soybean country…the “farmers” generally rotate between the 2 crops…allowing the beans to fix nitrogen for the corn. More recently there has been a LOT of tiling of the fields for better drainage. They are also clearing most hedgerows of trees and growth…removing old farm fences…etc. Seems a lot like factory farming…with many farm supply type places getting built here and there. Guess they are selling lots to China…etc. This time of year they are out pre-spraying the fields with herbicides (glycophosphate?) where they drive fat tired spray trucks over the fields before planting….not the time you want to be out walking in the country. They are mining the soil?

  • Panchito

    There may be pocket gadgets coming up soon that could tell shopers if the vegetables have pesticides and which types. That could change the industry by empowering people at the time of purchase.

    • Joseph Gonzales R.D.

      Interesting! A lot of backers it seems.

    • Wilma Laura Wiggins

      Interesting, yes. I hope the price drops a lot soon.

    • baggman744

      TellSpec looks very interesting. Although for consumer use, kinda expensive, and subscription based, but I imagine that’ll change. I think their research should be supported. I see it has the potential to display other important information such as possible allergens, calories, macro nutrient content, etc. And I assume it can be customized as well, e.g., someone with a nut or fish allergy can scan food for safety. Kinda awesome. Imagine if it can scan & detect things like salmonella, E. coli, and other bacterial/ viral/ hazardous infections.

      A 21st century tricorder…

  • Jeff and Karen Hay

    The Paracelsus Axiom – “The dose makes the poison” is no longer relevant to all toxins as endocrine disrupting chemicals are often more dangerous at lower levels of toxicity. This is because the hormonal signals that take place within humans (particularly in the womb and in early childhood) happen via chemical signals that are often equivalent to parts per quadrillion and are mimicked by certain chemicals at extremely low levels. In fact, at higher levels some of the same chemicals do not appear to be toxic. For more information on endocrine disruptors see “Our Stolen Future” by Theo Colborn. When the endocrine system is disrupted it produces other diseases than just cancer so looking for cancer as the result of eating poisons (i.e. pesticides) is too reductionist.

    Another thought relative to this examination of the health benefits of organic compared to “conventional” is to examine it from a more holistic perspective including toxicity to the soil, water, air, pollinators etc. Certainly un-poisoned water, air and soil makes for a more healthy environment for humans and other animals. Additionally, the intuitive revulsion that nearly everyone feels at knowledgeably eating poisoned food should not be discounted whether it is entirely scientific or not. We once ran an educational display at our farmers market on the potential hazards of genetically engineered organisms in food – we had a shopping basket full of foods that had genetically engineered organisms in them and we labelled them as such. We told people that if they would listen to our 3 minute informational on the possible hazards they could take any of the food out of the shopping cart that they desired. NO ONE after hearing the information ever took an item from the shopping cart. This included destitute people.

  • Scandinavian
  • Wade Patton

    Grown YER own! Vegetables are MUCH more interesting than lawns.

  • JohnC

    It should be pointed out that organically grown crops may legally be grown using fertilizers sourced from animal factory farm waste, or even such animal waste applied directly on fields. I am not aware that there is any requirement that such fertilizer be tested for pesticides or other contaminant.
    This was confirmed recently by the Organic Consumer Association, which issued an action alert on the subject:

    “Waste from factory farms, or Concentrated Animal Feeding Operations (CAFOs), as the Environmental Protection Agency (EPA) calls them, is being used and marketed as an “organic” fertilizer.

    “That’s a problem, because factory farm waste is contaminated
    with hormones, antibiotics, pesticides, disease organisms, heavy
    metals, and other undesirable substances, including some disease-causing
    agents, such as e.g. Salmonella and E. coli bacteria, that may survive the composting process.

    “Fortunately, the National Organic Standards Board (NOSB) is discussing
    plans to address the problem. We want the NOSB to recommend that
    factory farm waste be banned from use from organics. – See more at:

  • Charzie

    Whenever I hear about all the chemical sprays, insecticides and pollutants that are dumped onto and into everything these days, I go a little berserk that it continues unabated How did we let it get this way? We are killing ourselves and taking everything else with us and all we can do is tolerate it and be outraged? What’s it going to take to make reality sink in to these jackasses that changes are needed yesterday? Everyone I talk to seems to shrug and say “what can you do?” I just don’t get the apathy, what is wrong with us? Ha ha, well…..

  • Loreen

    What is the best turmeric or curcumin to consume seeing that stomach acids are claimed to kill off the nutrition and cancer fight properties of curcumin?

  • Victoria Whitehead

    Hi Dr Greger, I have read that Vegetarian Women are 5 times more likely to have a child with Hypospadias. Have you looked into this, and what do you think may be the determining factor. Apart from eating organic, is there anything else we can do to prevent this. Thank you.

  • RMK

    I began my career as a Metabolism and Residue chemist on pesticides.
    Firstly, a pesticide must be water soluble; you can’t spray organic solvents
    around the farm. As such, if you carefully wash your vegetables you will remove
    the pesticides. The pesticides that enter the root/skin system of the vegetable
    are readily and effectively metabolized by the plant. Don’t underestimate the
    power of a plant to metabolize a molecule. I eat and buy what looks the best.

  • Michael

    I’m 100% on board with Plants instead of Animals, but have any studies been done comparing Plants vs Organic Animals? I’m looking for the scientific reason not to eat Grass Fed Beef or Organic Chicken.

    • Thea

      Michael: Following is my standard answer to this question. Here’s the conclusion up front: There may be *marginal* health advantages to an animal product raised “naturally”, but in the end, the main problems are inherent with the product themselves regardless of how the animal was treated.

      Dr. Don Forrester wrote:
      “[humans] are designed as “hind gut fermenting herbivores” a lot of data to support the anatomy and physiology of this hypothesis. Beyond that meat from grass fed animals also contains saturated fat which is metabolized to cholesterol and dioxins…see which are in the air as a product of burning plastics. It is true that grass fed animal meat is healthier then animals via CAFO’s but that doesn’t make it healthy.” … “[Some people may have] a similar argument about fish which is even easier to address see video…

      And Toxins also wrote an excellent reply:
      “endotoxins, xenoestrogens, increases in igf-1 and arachidonic acid. All are inherent components of meat whether organic or conventional.

      I would add saturated fat and cholesterol to the list of problems. Another point I like to make is that people who push meat like to talk about primitive cultures who ate mainly meat. Before modern times, those animals would have been more naturally raised or wild animals. And yet we have plenty of evidence that people eating those animals suffered bad health consequences by eating those animals. It’s not a 30 second sound-bite, but if someone wants to learn more about those arguments and counter-arguments, Plant Positive has a very scholarly and fully referenced set of videos on YouTube.

      Or you might check out the website by HealthyLongetivity. Here is a quote from that site:
      “I have already posted several articles describing the poor health of populations who subsisted predominantly on naturally raised animal foods which you can find below:

      Here is another quote from Healthy Longetivity:
      “It is well established that saturated fat (in specific lauric, myristic and palmitic acids) raises total and LDL cholesterol, and that LDL cholesterol is an established cause of cardiovascular disease. The cholesterol raising effects of saturated fat is not the result of how the animal was raised as tropical plant fats high in lauric, myristic and palmitic acids will also raise total and LDL cholesterol.

      As I previously pointed out, it has been demonstrated in thousands of animal experiments that the feeding of cholesterol and saturated fat, including in the form of fresh egg yolk accelerates the development of atherosclerosis in virtually every vertebrate species that has been sufficiently challenged. This includes mammalian, avian and fish species- herbivores, omnivores and carnivores, and over one dozen different species of nonhuman primates. Again this cannot be attributed to the way that the animal was raised as when taking into consideration the amount of antioxidants and carotenoids as well as the lack of cholesterol, tropical plant fats high in lauric, myristic and palmitic acids will also accelerate atherosclerosis in animals to a similar degree as saturated animal fats.

      It has been shown in controlled feeding trials that heme iron from meat causes the production of NOCs (N-nitroso compounds) in the digestive tract which in-turn causes DNA adducts in the human digestive tract. Therefore the heme iron content in meat rather than how the animal was raised can partly explain the positive association between red meat and colorectal cancer.

      *My* bottom line is: There may be *marginal* health advantages to an animal product raised “naturally”, but in the end, the main problems are inherent with the product themselves regardless of how the animal was treated.

      Hope that helps.

      • Thea

        Michael: Ooops. Sorry for the formatting problems. I got the formatting fixed on line. If you want an easier time reading my reply, click to see it on the NutritionFacts page itself.

  • One Step

    Thanks for this very balanced and insightful summary, Michael!

  • Robert Haile

    My wife accidentally bought apples that she thought were organic. I could taste the pesticides and then checked the labels to see they were non-organic. Pesticides also taste bad.