The dose makes the poison. While anything is lethal in a high enough dose, low amount of toxins often cause a favorable biological response called hormesis. Relevant food toxins include man-made synthetic pesticides, natural plant toxins (as protection against insects and mold) and toxins generated in cooking. Surprisingly and contrary to peoples’ believe 99.99% of consumed toxins are of natural origin. Quantitatively, it seems reasonable to focus first on natural toxins.

Plants always contain toxins

Animal foods generally don’t contain toxins. As human and animal biology are similar, compounds toxic to humans would harm their host as well. If toxins appear in animal food, these are usually in farm raised animals and come from contamination with bacteria or virus.

Plants have a different biology and can produce compounds toxic to us but safe to them. As they can’t run away, that is their defense mechanism against being eaten. While toxins primarily targeting insects may hardly affect us (although they can when over consuming any one plant), toxins used as defense against herbivorous mammals will harm us.

▶ Take away:

• The dose makes the poison: Do not eat too much of any one plant but diversify over a wide variety.

Grains (cereals and legumes) are especially toxic

Grassland plants and their seeds eaten by mammals have evolved severe defence mechanisms.

Their high content in anti-nutrients make its nutrients impossible or uncomfortable to digest and greatly reduces the digestibility of minerals [2] and protein [2,3]. That is the reason why grains are a poor choice in terms of bioavailable nutrients.

All grains have similar other toxins. Wheat – the worst grain – contains substances (e.g. gluten, opioids, WGA) that can cause irritable bowel symptom (IBS) and increase intestinal permeability (‘leaky gut’) [2,3,4,5,6], whether you think you’re sensitive to gluten or not. A leaky gut can cause chronic inflammation [2], not only in the gut but also in the rest of your body, particularly your joints and can result in autoimmune diseases [2,3]. Wheat also promotes cancer [2,3,4], neuropathy, heart attack and increased mortality rates in gluten-sensitive and diseased population. Grains, and particularly wheat, are strongly associated with schizophrenia [2,3,4,5]. Furthermore wheat links to rickets [2,3,4,5,6,7,8] and vitamin D deficiency [2].

So far you probably think: “So what – as long as I am in shape”. That is why I saved the most prominent arguments last: Wheat consumption promotes ‘man-boobs‘ and obesity [2,3] regardless of total calorie consumption by altering your hormones. It even reduces IQ and brain volume. Soy consumption is associated with erectile disfunction in men.

While herbivorous mammals have evolved mechanisms (e.g. digestive organs such as rumens) to ferment these compounds with help of bacteria, we are more or less defenseless. You may argue that grains have been part of some cultures’ diet historically. That is correct, there is even evidence dating back to 103,000 BC. However, grains just recently (in evolutionary terms) became a staple of the human diet with the onset of the agricultural revolution in 10,000 BC. Before, they were most likely just a seasonal backup or starvation food. Furthermore, grain consuming cultures use(d) detoxification methods which include very long cooking times, (overnight) soaking, sprouting and fermenting. But even then not all toxins are removed. And most importantly: The effect of ancient and modern wheat on your digestion differs significantly.

The only reason wheat is so popular is because people are lazy, wheat is cheap and it can be highly addictive thanks to containing morphine-like opioid peptides [2,3]. I know how tough it is to give up bread, but there might be no other single step improving your health more.

▶ Take away:

• As the traditional preparation of grains is an absolute exception nowadays, both satiety and nutrient profiles are poor while caloric density is high eliminate grains and especially wheat completely from our diet.

Vegetable seed oil is toxic too

It contains the plant’s toxins and in addition is loaded with omega-6 fatty acids, which are essential to the human body at low doses but toxic in high doses. Excessive intake of omega-6 fats is primarily caused by the overuse of vegetable oils and causally linked to increased mortality rates [2], cardiovascular disease [2], cancer, mental illness, obesity. It also impairs the immune system [2].

▶ Take away:

• Vegetable oils are to be eliminated from our diet.

Industrial food toxins are dangerous too

There can be two kind of toxins in industrially processed food: Toxic ingredients such as bleached and degummed vegetable oils [2] and toxins created during food processing [2,3] such as trans fats [2,3]. Furthermore, industrially processing does not reduce the content of natural plant toxins to the same extent than preparation of the same food at home does. While (uninfected) meat is healthy [2], processed meat is not [2,3] and increases your risk of heart disease. If you are tolerant full-fat, raw dairy is healthy while processed (= pasteurized and homogenized) dairy is not [2].

There is evidence that organic produce is more healthful than conventionally grown produce. However, more important seems to be the nutrient content of the soil which is something the label itself does not tell anything about. Local even beats organic produce in respect to nutrient content. The effects of genetically modified food (GMO) are not yet fully understood, but it seems likely that it negatively impacts health.

▶ Take away:

• Steer clear of industrially processed foods, including processed meat and milk.
• Buy unprocessed meat, full fat dairy and whole foods instead. Preferably from local and organic producers. If you want the silk ribbon of excellence buy grass-fed (instead of grain-fed) beef and dairy.

Excess fructose sugar is harmful

While normal consumption of fructose from low-calorie plants (fruits, berries and sugary vegetables such as carrots and beets) is very healthful, high doses from sweeteners or sweetened products (sugar, high-fructose corn syrup, candies, soft drinks) can be very dangerous: Excess fructose increases abdominal fat and promotes high risk for cardiovascular disease and type 2 diabetes [2,3,4,5,6,7], gout [2] and kidney disease. There is a strong link between high fructose intake and obesity [2,3,4]. In rats high fructose impairs memory and shortens life.

▶ Take away:

• Skip sweeteners (sugar, syrup) and sweetened products (candies, soft drinks).

Cooking matters: It can reduce but also create toxins

Toxins in plants such as taro, cassava/tapioca, white rice, sweet potatoes, potatoes, yams and sago (so called “safe starches”) can be eliminated by cooking. However, cook gently to prevent toxin formation: High temperatures are diametral to health and create cancer promoting substances in meats above 400°F / 200°C [2,3,4] and plants. Starches form carcinogenic acrylamide above 250°F / 120°C. Therefore, steaming or boiling are preferred options to prepare starches. Instructions on safe cooking can be found here and here.

Beware of eating farm-raised pork raw and cook it thoroughly (at 160°F / 70°C) to destroy potential pathogens [2].

▶ Take away:

• Cook meat (below 400°F / 200°C) and plants (below 250°F / 120°C) gently.
• Cook starches and farm-raised meat, especially pork (at 160°F / 70°C), thoroughly.

Take action and eliminate toxins

You will greatly benefit from executing following steps:

▶ Action Step I: Eliminate

• Cereals: No foods made of or containing wheat, maize, barley, oats and brown rice. Yes, this includes pasta, bread, pizza and beer.
• Legumes: No beans, lentils, soy, peas or peanuts.
• Vegetable seed oil: No soybean, corn, safflower, peanut and canola oil.
• Industrially processed and produced food: This includes McDonalds & Co. and almost all pre-prepared meals.
• Processed dairy and cured meat: No skim milk or fat-reduced dairy products, no sausages
• Excess sugar: No sweeteners, sweetened products, candies, soft drinks and juices.

▶ Action Step II: Diversify

• Do not eat too much of any one plant but diversify over a wide variety.

▶ Action Step III: Cook gently

• Cook meat (below 400°F / 200°C) and plants (below 250°F / 120°C) gently.
• Cook starches and farm-raised meat, especially pork (at 160°F / 70°C), thoroughly.