Today, I want to talk to you about something I recently changed my mind about. This is tricky, and it might come off as controversial, but I really want to share the best data available and what we can learn from it. So, let’s dive into the world of pesticides.

I like organic food. When I have the choice, I do prefer it over the alternative. There has been data I have been saying that says it might be higher in certain nutrients. I have also seen some data saying that some phytotoxins (naturally-occurring insecticides), might also be higher in them. These are the things that are good for us.

There is also the argument that organic foods may be better in terms of their environmental impact. Many consumers feel, though, that they must consume organic foods to avoid their exposure to pesticides.

Let’s be honest: none of us want to be exposed to harmful things in the foods we eat. In fact, we want to be aware of what we’re putting into our systems.


Looking Into Toxicology Data

A few months ago, I was looking into some toxicology data and the methods by which these aforementioned lists were formulated.

As I went through it some more, it became clear that the messages they had were ones that I could not endorse. The basic version is that we’re at a point where we can measure things in food at levels which are far below significant.

This leads me to suggest considering our overall exposure. Just how much are we getting in our bodies? And how much of that is dangerous?

The Dirty Dozen & Clean Fifteen

What I have come to realize is that to tell someone that they should eat organic is not a valid message. To be more specific, the idea of the “dirty dozen” and “clean fifteen” is something that I really want to talk about.

Where does the idea of the “dirty dozen” come from? Well, it starts with an annual report created by the USDA, in which they take about 10,000 different foods and do many samples of them.

dirty dozen
Altogether, we are talking about approximately 2 million data points! The report itself includes a lot of things that are important, but the dirty dozen focuses exclusively on the number of pesticide residues in certain foods.

So, the interesting thing here is that the quantity is not taken into account. Or, whether the amounts of pesticides are at a level of danger. Instead, it’s just the number of residues there.

Measured Pesticides in Organic Produce

The other consideration here is that, in the case of organic produce, there are a number of pesticides that are not even measured. This is because they do not fall into the reporting process – so, they are not tracked.

Key Insight: The Dirty Dozen only looks at the number and not the toxicology therein.

If a food came through that had a harmful amount of two pesticides, and another that had completely harmless amounts of three pesticides, the food with three pesticides would rank worse simply based on the number of them (and not how harmful they are).

Bottom Line: The Dirty Dozen’s ranking system is ineffective because it denies the actual toxicology of certain foods, instead focusing simply on how many pesticides there are – that might sound worse, but it often is not the case.

Dosage & Toxicology

One of the things I want to hammer home during our discussion today is that dosage and toxicology really has to matter. We truly cannot avoid all pesticides in our food, unless we intend on eating no food whatsoever.

Even when we do choose to eat organic, we are not avoiding pesticides. I will come back to this later, but for now, let’s leave you with the fact that plants even create their own pesticides to ward off insects and other predators!

Toxicology has something called the “no observable effect limit” (NOEL), and NOEL is basically of determining whether something can be considered dangerous or not. Scientists will look for changes, in animals, due to toxicity levels that may affect:


  • Cognitive function1
  • Liver enzymes
  • Glucose regulation

How it All Works

Basically, they are looking for the first detectable thing that shows up when exposed to certain levels of toxins – at what point it shows up and in what form. From there, they determine how low you can go before you cannot see any change at all. That’s NOEL.

dirty dozen

Key Insight: There are no chemicals that are dangerous at every dosage. There is also nothing that is completely harmless at every dosage. The same can be said of water – which, if you drink too much, can be harmful, but is advisable to enjoy a glass.

Chances are you have heard of DDT. This is likely one of the biggest reasons why people are concerned about pesticides in general. It was banned in the early 70’s, but it is still around to this day. There is even lots of it on organic food.

That’s not because it has been sprayed on, though, it is because it has bio-persisted. Toxins are everywhere, and we could never be able to get to a zero-pesticide level simply because of that fact. They are here to stay.

Bottom Line: This is why we have to clearly identify which pesticides are dangerous, and in which amounts (think about NOEL) are dangerous – and how much are we going to be ingesting along with our food? The Dirty Dozen does not consider this.

Which Pesticides Persist in the Environment?

While DDT was awful, it did force a new level of thinking into pesticides and loads of research looking into how they play their role in the environment (and which ones are still around).

And, there is some key overlap between which ones stay in the environment and which ones bio-accumulate within hosts (such as people).

Based on the chemistry, it is rather simple for toxicologists to know which chemicals are likely to persist and which ones are not.

There are two terms I want to dig deeper into:

  1. Hazard, and
  2. Risk

Often confused, science will often speak in terms of hazards without outlining what makes a hazard different from risk.

A hazard is something that could harm us. Electricity, for example, which is something that could harm us in certain situations, is a hazard.

A risk, on the other hand, is the increased likelihood of something that is hazardous causing direct harm. Like being hit by lightning, which is simply electricity in another form which may be safe if it was powering a lightbulb or our computers.

Bottom Line: The Dirty Dozen, at its core, conflates hazard and risk. Any pesticide, in large quantities, can be harmful – no question about it. But the quantity is what matters because potency is what counts when we are talking about anything toxic.

How Organic is Organic?

Folks often assume: if you are not sure, just buy organic. But, is this the right way to be going about things? Are you avoiding pesticides by shopping organic?

The pitfall here is that organic foods do not avoid pesticides. At all.

In fact, organic is grown with pesticides, and many of them are synthetic (meaning that they are not organic or naturally-occurring in said plants).

Organic guidelines call for them to be ones that are naturally-occurring, but some of these growing practices take that definition and stretch it pretty far out there.

Copper Sulfate

One of the most bio-persistent and toxic pesticides out there is organic! It’s called tribasic copper sulfate, and it has been shown to:

  • Persist in the environment
  • Be a factor in human and animal toxicity
  • Damage soil microbiome
  • Become toxic for marine animals

This is a pesticide that is exclusively used by organic farmers, and yet all of these things are not true of other synthetic pesticides out there on the market. So, while I do not think it is used in irresponsible ways, it could be a great danger in higher quantities.


(Click Here for image reference)

Key Insight: It is too easy to say organic is good and conventional is bad. We have to break it down, per chemical, to determine how these things are used and the kind of effect they can have where they to accumulate over time.

What Really Matters in Organic versus Conventional?

We should try to get away from thinking in terms of synthetic and natural, organic versus conventional, because, ultimately, produce is good for us!

The evidence of produce being helpful is simply impossible to ignore. It helps with:

  • Cancer risk
  • Cardiovascular disease risk
  • Blood pressure
  • Brain aging
  • Visual function
  • Kidney health
  • Diabetes risk
  • Obesity

Key Insight: I could go on, but the fact remains: produce is good for us and we should be looking at more and more ways to incorporate it into our diets. No question about it.

If the pesticides in our produce supply were a real danger or a real concern for us, people would not have been healthier in all of the ways that I just mentioned. In fact, it would likely be far more the opposite.

Bottom Line: We see clearly, in the data, that those who eat more produce see better health outcomes – dismissing the idea that, if it was a question of dose, that pesticides would be linked to poorer health overall due to produce consumption.

Should You Eat Less Produce?

My issue with the Dirty Dozen is how it affects consumer buying habits. When consumers hear the message about pesticides in their food, they typically end up eating less produce overall – and not switching to organic at all.

dirty dozen

This is a huge issue for me because that outcome does not improve people’s health overall. So, the Dirty Dozen’s message is effectively falling on deaf ears, because people not only become more afraid of conventional produce but produce overall.

Again, the data is overwhelming. People who consume more produce are healthier than those who consume less.

Naturally-occurring Pesticides

This is something that I mentioned earlier and promised that I would expand on when the time came. So, basically, we have three types of pesticides:

  1. Synthetic
  2. Organic
  3. Naturally occurring

I want to focus on naturally-occurring pesticides, those which the plants create themselves. There was a large study performed in which researchers looked at 50 of the known pesticides which plants create on their own.2

This is What They Found

“[R]odent carcinogens are present in the following foods: anise, apple, apricot, banana, basil, broccoli, Brussels sprouts, cabbage, cantaloupe, caraway, carrot, cauliflower, celery, cherries, cinnamon, cloves, cocoa, coffee, collard greens, comfrey herb tea, currants, dill, eggplant, endive, fennel, grapefruit juice, grapes, guava, honey, honeydew melon, horseradish, kale, lentils, lettuce, mango, mushrooms, mustard, nutmeg, orange juice, parsley, parsnip, peach, pear, peas, black pepper, pineapple, plum, potato, radish, raspberries, rosemary, sesame seeds, tarragon, tea, tomato, and turnip. Thus, it is probable that almost every fruit and vegetable in the supermarket contains natural plant pesticides that are rodent carcinogens. The levels of these… rodent carcinogens in the above plants are commonly thousands of times higher than the levels of synthetic pesticides.”

That’s a lot of food! The ratio of the pesticides that a plant makes on its own is around 10,000:1 of the number of pesticides that you would get from commercial produce.

The truth is, though, that the amounts of naturally-occurring pesticides in the plants above are not going to be harmful in the typical diet. It is more to make the point of not being afraid of commercial pesticides given the ratio.

Key Insight: Please, feel free to add more and more produce to your diet – in great varieties and with little fear. That is what I want you to take away from today’s discussion.

What’s A Consumer to Do?

If you have become concerned about pesticides affecting your health, there are some things that I want to help you think through.

People who eat more produce are healthier than those who eat less. This is just not debatable – it’s fact.

If the effects of produce were net negative, we would not see such a robust section of data showcasing all of the positive contributions it can make to our lives.

Instead, we would see consumers have worse health when consuming more produce.

If you like organic, as I do, in terms of the flavor or supporting farmers, then please go for it whenever the opportunity presents itself.

At the same time, you should not be afraid of commercial produce. Be more afraid of avoiding produce altogether, instead.

Key Insight: Do not avoid commercial produce based on pesticides – enjoy it, instead! Choose organic when you can, if you want, but continue to eat more and more produce.

Things to remember, though, include washing your produce, not using soap, and storing them properly (which should go in the fridge and which should not).

How Much Is Plenty Produce?

Plenty of produce is really as much as you should get! But, let’s think in terms of variety, like:

  • Greens
  • Allium
  • Crucifers
  • Apiaceae
  • Berries
  • Mushrooms

All of these are great, every single category. Include them in your diet, enjoy them, and do not be afraid of pesticides. You have nothing to worry about.

Changing Minds on Pesticides

So, I told you a little bit more about how I feel on pesticides, why I don’t believe in the Dirty Dozen list, and how you should feel empowered to include more produce in your diet.

At the same time, you should feel empowered every day to take your health and run it on your own terms. Part of that begins with a comprehensive understanding of it.

So, please, after enjoying an apple or a serving of beans, consider taking the Thyroid Quiz (Click Here) today to get a better read on your health. Talk to you soon!


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Dr. Alan Glen Christianson (Dr. C) is a Naturopathic Endocrinologist and the author of The NY Times bestselling Adrenal Reset Diet, The Metabolism Reset Diet and The Thyroid Reset Diet.

Dr. C’s gift for figuring out what really works has helped hundreds of thousands of people reverse thyroid disease, lose weight, diabetes, and regain energy. Learn more about the surprising story that started his quest.