This post is more one for thought and speculation. There are concerns over the pesticides used on plants to prevent them from being eaten. These pesticides serve a purpose and allow produce to grow and make it to supermarket shelves without being eaten. But one study has concluded that 99.99% of pesticides are naturally produced by plants. This is both surprising to many, but unsurprising when you think about it. Here’s why.

Plant Defence Mechanisms

Just like animals, plants don’t want to be eaten. They want to survive and thrive. Animals have claws, teeth, tough hides, can move and more. Plants don’t have these characteristics which is why they employ other mechanisms of self defence, the main one being producing pesticides.

Plants Produce Pesticides

In this scenario a pesticide is a substance used for destroying insects or other organisms harmful to cultivated plants. This is the main way that plants deter predators from eating them whether it’s insects or animals. Compounds such as caffeic acid, commonly found in (you guessed it) coffee is one such pesticide, and one that many consume on a daily basis.

We cook most of our food which helps to destroy harmful pesticides that may be present in food. Interestingly, many of these pesticides we consume are actually what we consider to be ‘antioxidants’. There are many health benefits associated with these antioxidants, but does it actually make sense for these pesticides or antioxidants to be beneficial to us if they’re actually produced to deter predators from eating them? It’s a nice question for thought and I’ll dive into why these pesticides might be beneficial for us.

Natural Pesticides And Antioxidant Consumption

There’s the odd story in the news here and there about how someone consumed too much caffeine and died from it, yet billions of people around the world consume coffee on a regular basis and never have a problem. Some people become habituated to the effect of coffee and require more coffee in order to get the caffeine hit they’re seeking out.

Humans have an exceptionally capable body which is able to take care of and handle many toxins and pesticides. The response from the body after dealing with these pesticides is to produce antioxidants which effectively makes the body more robust. So what we see is that it’s not the blueberries and coffee which are providing the so called antioxidants, but rather they are inducing a stressor on the body which causes the body to produce antioxidants to deal with the stress. These antioxidants are good for our health, helping to deal with free radicals in the body. Free radicals are known to be carcinogenic, so having antioxidants to neutralise them is great.

So having some stress is good, too little and there is a negligible effect. Too much and you’re probably hampering your immune system. Exercise is one great example of this.

What Doesn’t Kill You Makes You Stronger

This is a great song by Kelly Clarkson by the way! That aside, there’s a concept known as hormesis which you should try and make yourself familiar with. There are three main components to hormesis: stressor, dose and response.

Stressors can be both beneficial and detrimental to health. Too much of a stressor and your health is likely to deteriorate e.g. chronic exercise, mental burnout, inflammation. Too little of a stressor and your body is unlikely to respond to the stressor e.g. wanting to run faster but only running three times a month. If you subject yourself to enough dose of a particular stressor, your body is likely to respond in a way that’s beneficial and makes you more resistant to the stressor. In other words, you get stronger or more antifragile.

We see the same with other plant compounds such as alcohol and caffeic acid. People who regularly consume these compounds start to build up a resistance to them. One could argue that such resistance is beneficial. However, in the case of these two plant compounds, people actually start ingesting more because they want to get drunk or feel a caffeine high. In these instances, it can actually be better if you have a period where you refrain from consuming these substances so your body can reset and you don’t need to consume as much coffee to get the same caffeine hit.

Disclaimer – I’m not advocating for large amounts of alcohol or caffeine consumption! I’m just using it as an example.

How Many Natural Pesticides Do We Consume?

If these natural pesticides are present in so many plants and plant compounds, how many are we consuming each day?

Well, Dr Bruce Ames, one of the scientists of the paper estimates two things:

  1. We consume 5,000 to 10,000 different natural pesticides each day, many of which cause cancer when tested on lab animals.
  2. Americans consume around 1.5g of natural pesticides each day, which is 10,000 times higher than they eat of artificial pesticide residues.

Another impactful statement in his literature is:

[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.

Based off this I certainly don’t think we should be trying to avoid eating vegetables since there are many documented health benefits of consuming vegetables. However, I wouldn’t go about trying to eat 1kg of spinach, broccoli or some other vegetable for the antioxidant response.

Artificial And Natural Pesticides

So, we come to the question – are artificial pesticides far worse than natural pesticides?

Well, pesticides serve the purpose to deter plants from being eaten. We’re able to tolerate a large amount of pesticides without any issues. If you’re choosing organic food to avoid pesticides as a whole, then you’re probably wasting your money since many pesticides are naturally produced. If anything, natural pesticides aren’t so much of a concern.

However, there is reason to avoid artificial pesticides such as glyphosate which have been shown to have a high possibility of being carcinogenic. Artificial pesticides have been linked to risk factors such as increased risk of cancer and diminished health outcomes. They also have a negative effect on the environment as artificial pesticides contaminate crops and can kill beneficial insects such as bees.

You can better remove pesticide residues by washing your fruit and vegetables before consuming them.

Ideally, we should aim to avoid artificial pesticides as much as possible, but then again maybe it’s not so much of a concern given that we consume far more natural pesticides. I don’t know. Just a point for thought.

Final Thoughts

Natural pesticides cannot be avoided and instead of being afraid of pesticides, we should aim to avoid artificial pesticides. Organic produce is great if you can afford it, but perhaps not worth the extra cost. A better way to avoid artificial pesticides would probably be by avoiding the “dirty dozen” and focusing on consuming the “clean fifteen”. These are the vegetable produce which contain the most and least pesticide residues.

My personal view is we should aim to be healthy by avoiding chronic stress, exercising with a mix of aerobic activity and strength training, eating nutrient dense whole foods, practising mindfulness and being positive!

I’ll likely do a post later on about whether we need the antioxidants induced by consuming plants since the main one produced is glutathione, the “master antioxidant”. And this can be produced in a variety of ways – not just eating plants!

Thanks for reading! If you found this post informative, I’d greatly appreciate it if you could share it with friends and family!

Further Reading:

Earth Day – How You Can Care For The Earth

How Hormesis Can Improve Your Health

My Thoughts On Finding Your Optimal Diet

Running, Oxidative Stress, Free Radicals And Antioxidants


2019’s Dirty Dozen And Clean Fifteen – Green Matters

99.99% of Pesticides We Eat Are Produced by Plants Themselves – American Council of Science and Health

Caffeic Acid – Healthline

Dietary Pesticides (99.99% All Natural)

Free Radicals In Chemical Carcinogenesis

Glyphosate General Fact Sheet – Natural Pesticide Information Center

Hormesis – An Overview – Science Direct

New Studies Confirm Dangers of Glyphosate – New Eastern Outlook

Probable carcinogenicity of glyphosate – BMJ

Removal of 16 pesticide residues from strawberries by washing with tap and ozone water, ultrasonic cleaning and boiling