This was to be Part 3 of The Duck Dodgers’ “Hormesis Files” series, but it’s way broader than that. It’s beyond hormetic effects. Rather, think of it as anti-nutrients as nutrients. While you’re at it, contemplate yourself…as a tender little paleo flower, born of Trademark.
There’s a long list of phytochemicals and “anti-nutrients” that people in the Paleo™ and “Bulletproof” world tend to worry about and try to avoid. Among others they include: lectins, saponins, phytate, polyphenols (tannins, isoflavones), protease inhibitors, cyanogenic glycosides, and favism glycosides. Even mycotoxin problems might be related to gut health since ruminants have little problem with them. These phytotoxins and anti-nutrients are also known as secondary metabolites. But what is never mentioned in Paleo™ circles is that there are a number of scientific papers showing benefits to consuming marginal levels of all of these toxins.
Phytic acid, lectins, phenolic compounds, amylase inhibitors and saponins have also been shown to reduce the blood glucose and insulin responses to starchy foods and/or the plasma cholesterol and triglycerides. In addition, phytic acid, phenolics, saponins, protease inhibitors, phytoestrogens and lignans have been related to reduced cancer risks. Because antinutrients can also be mitigating agents, they need re-evaluation and perhaps a change in name in the future…It is evident that both adverse and health benefits may be attributed to antinutrients in foods. It is also evident that, in many cases, the same interactions that make them antinutritive also are responsible for their beneficial effects.
The dreaded kidney bean lectins have anti-fungal and anti-viral activities and lectins in general have anti-cancer properties too. Phytates have anti-cancer functions and therapeutic properties against diabetes mellitus, atherosclerosis, coronary heart disease and reduces kidney stone formation. Toxic glycoalkaloids, found in potatoes and nightshades, have been shown to offer antiallergic, antipyretic, anti-cancer and anti-inflammatory effects; blood sugar-lowering effects, and anti-pathogenic effects against viruses, protozoa, and fungi. Cyanogenic glycosides have anti-cancer properties. Phytosterols, polyphenols, flavonoids and tannins, alkaloids, phytates all have anticancer, antioxidant or endocrine normalization properties as well. Anyone noticing a pattern?
Of course, cooking is well known to reduce most plant toxins to levels that are safe to consume. For instance, while many raw legumes are well known to be very toxic, it’s also well known that cooking destroys virtually all bean lectins. Whatever trace amount of toxins that remain from fully cooked beans are likely to be hormetic given the overwhelming evidence of longevity we see from the high levels of legumes and potatoes consumed in the Longevity Villages and Blue Zones of the world.
Wild Plants Are Toxic, of Course!
How anyone can believe that any wild plant can survive in a rainforest, a jungle or a savannah without a toxic defense system is beyond comprehension.
Furthermore, while indigenous cultures gravitated towards low toxin plants, and often took steps to reduce toxins in those plants, they did so in the context of wild plants that had significant levels of these toxins. They didn’t have the luxury of domestication.
To put this in perspective, we can look at the death of Chris McCandless. McCandless was an American adventurer who ventured into the Alaskan wilderness in 1992, hoping to live off the land. Four months later, McCandless’s starved remains were found, weighing only 30 kilograms (66 lb). Chris McCandless ate raw seeds from the alpine sweetvetch (Hedysarum alpinum) plant. The potato tubers from the plant are non-toxic and are eaten raw by the Eskimos, who steal them from mice with the help of their dogs trained to find them. However, the raw seeds are extremely toxic and contain L-canavanine, which paralyzed McCandless’s legs and made him too weak to obtain food. That’s the kind of plant toxins our ancestors had to avoid in the wild.
In the modern world, one of the major reasons for the domestication of plants is literally to hybridize and breed out the toxins from them. Domesticated plants are then coddled in fields with perfect growing conditions while pests and hungry scavengers are kept away so that they don’t have to produce all the toxic compounds they needed to survive in the wild. Our Paleolithic ancestors would easily scoff at the toxins Paleo™ gurus have scared people into avoiding.
Debunking Paleo™ Toxins
Paleo™ authors often use the Masai and Inuit to promote their low carb narratives of high meat and fat consumption—never mind that those two cultures are the exception and not the rule. The Paleo™ narrative suggests that they are healthy because they supposedly avoided plant toxins and anti-nutrients by favoring meat.
Except it’s not true.
These two cultures actually went out of their way to consume the very plant toxins and anti-nutrients that Paleo™ authors warn about.
For instance, it’s well documented that the Masai constantly consumed a lot of milk, honey and some rather “toxic” plants alongside their meat and fat. One such example is the highly toxic East African Greenheart (Warburgia ugandensis), known locally as Olsokonoi whose cytotoxic bark and toxic leaves are used as a spice and is known to have powerful medicinal properties. Another example is Acacia nilotica, which has been shown in studies to have toxic secondary metabolites that promote anticholesterolemic and anti—pathogenic effects:
Food Cultures of the World Encyclopedia, edited by Ken Albala
Soups are probably the most important medium for consumption of wild plant food by the Maasai. Okiloriti (Acacia nilotica), a powerful digestive, is the most frequently used soup additive. The root or stem bark is boiled in water and the decoction drunk alone or added to soup. The Maasai are fond of taking this as a drug; it is known to make them energetic, aggressive, and fearless. Soups prepared during the time of a meat feast are laced with bitter bark and roots containing cholesterol—lowering saponins. Some that are added to the finishing stew on the last day of feasting have strong purgative or emetic effects.
It’s safe to say that indigenous cultures weren’t afraid of mind-altering compounds—not exactly a culture that fears its ingredients.
In a comprehensive study by McGill University, 82% of the most common plant food additives heavily used by the Masai contained anticholesterolemic compounds including polyphenols, phytosteroids, water soluble dietary fibres, antioxidants, flavanoids and saponins. The researchers hypothesized that these “toxins” allow the Masai to maintain low cholesterol from their high fat diets, and likely plays a role in the very low incidence of coronary heart disease among the Maasai. Although there are many other variables to consider, studies show that urban Masai, who don’t have access to these plants, have higher cholesterol and more heart disease than the rural Masai.
With that obvious difference between wild and domesticated plants in mind, if one actually takes the time to investigate the dozen or so wild plants cataloged by the McGill researchers, you’ll find that the Masai specifically targeted plants that contain all of the toxins Paleo™ gurus would have you fear. In other words, it may very well be that avoiding these plant toxins may be counterproductive in the context of the very high fat diet that Paleo™ gurus advocate.
What about the highly carnivorous Inuit? Some of their favorite edible weeds included dwarf fireweed (Chamerion latifolium) and alpine mountainsorrel (Oxyria digyna) both of which are an antiscorbutic, and both contained a lot of plant toxins and anti-nutrients. Dwarf fireweed happens to be a rich source of flavonoids, phenolic acids and tannins and lipophilic compounds such as steroids and triterpenoids. I doubt it’s a coincidence that these are the same exact “toxins” that the Masai intentionally sought out. Fireweed also possesses antimicrobial, antifungal, antiviral and anticancer agents. Canadian indigenous cultures were known to utilize it in their foods and make decoctions from it. Like many plants, it’s a useful food to maintain health.
The Inuit’s wild alpine mountainsorrel is listed in the FDA’s Poisonous Plant Database due to its high levels of oxalates and anthranoids. You have to wonder why a culture that can supposedly get by on meat alone goes through the trouble of collecting toxic plants whenever they can find them.
Eskimos were also very fond of drinking boiled extractions of Labrador tea (Ayuq) with their frozen meats. Labrador tea is made from the leaves of a highly toxic Rhododendron plant that blankets the frozen tundra. Labrador tea has narcotic properties and contains tannins and the poisonous sesquiterpene ledol. Excessive consumption of the plant may cause delirium or poisoning due to the terpenes of the essential oils, which can cause symptoms of intoxication, such as slow pulse, lowering of blood pressure, lack of coordination, convulsions, paralysis, and in rare cases death. But these toxins also provide antioxidant and anti—inflammatory activities.
As you can see, even the cultures that were known to eat high meat and high fat diets went out of their way to consume plant toxins. And if you take the time to investigate it, you will find that every indigenous culture obtained a daily dose of wild plant toxins.
We all know the Hadza relied heavily on Baobab (Adansonia digitata). The Baobab is perhaps the most famous “tree of life.” Baobab seeds contain anti-nutrients such as protease inhibitors, tannins, phytic acid and amylase inhibitors. The seeds are eaten extensively, though cultures actively take steps to minimize those antinutrients including sun drying, roasting and fermentation. Baobab bark has several flavanols and tannins, and terpenoids and its decoction is used to control malaria. The alkaloid ‘adansonin’ in the bark is thought to be the active compound for amelioration of malaria. Baobab bark—often given to infants to promote weight gain—was found to be high in fat, calcium, copper, iron, and zinc. Baobab leaves, rich in minerals like manganese, are a staple in Africa. They are nutritionally superior to the pulp, eaten fresh or dried, but the leaves are high in tannins, alkaloids, flavonoids and terpenoids while the stem bark is high in saponins and phenolic acids. Aqueous extract of the baobab pulp itself has saponins and triterpenes.
These properties aren’t particularly unique. Rather, they are fairly common in the trees and bushes that were most exploited by indigenous cultures. Researchers are finding therapeutic values from virtually all of these compounds that were regularly consumed by these cultures.
The Mbuti tribe ate toxic plants too…
“Many wild plant foods gathered by the Mbuti demand extensive processing before they can be eaten. This is particularly the case with yams which are also labor intensive to extract. Most edible yam species are either deep-rooted and/or contain toxins…Most tubers, and all stem bulbils, must be soaked and some boiled repeatedly before they become edible.”
Wild yams are not a major component of the Mbuti diet, but do the Mbuti shun these toxic wild yams. No, they do not. Toxic wild yams are real food to them.
Nor is their honey as tame as you might think. Honey is protected by an army of venomous stingers. And even “stingless honey” has its own defenses:
“The Mbuti say that too much ingestion of the honey of these stingless bees may cause mbenda, a sickness of joints and bones, which is possibly caused by some toxic substances in the nectar collected by the bees”
Not exactly the honey we find at the local farmer’s market, or Trader Joe’s. Toxic honey is isn’t all that surprising. Honeys sourced near toxic/wild plants are well known to contain toxins.
Few people noticed it, but even our beloved Tiger Nuts are full of Paleo™ toxins such as alkaloids, flavonoids, phenols, tannins, steroids, terpenoids and glycosides. Oh well.
Teas are an example of “tree/bush foods.” Teas and decoctions seem to have been very important parts of many traditional diets—Masaai, Bushmen, Inuit, Chinese, Indian, Persian, Turkic, Mongolic, Tibetan, Japanese, etc. There is even a “Tree food diet” (Bigu) that was used by Japanese monks. I think it would be hard to dismiss the importance of trees, leaves, barks and their anti-nutrition compounds in these cultures.
There is a long co-evolutionary history of trees/bushes and humans. Baobab is an early contributor. The fact of the matter is that plants need secondary metabolites/anti-nutritents to function and to protect themselves. It would appear that we use them to our advantage too. We obviously evolved with livers and gut flora that help us handle some level of these toxins. If we had always avoided these toxins, I doubt we could reap the benefits from them so easily.
Wild plants are more toxic than domesticated plants. This is not controversial. Do hunter-gatherers take steps to reduce wild plant toxins and do they make an effort to avoid highly toxic plants? Yes, of course!
However this does not necessarily apply to us Westerners who eat fairly coddled, hybridized and domesticated wimpy plants that happen to contain negligible amounts of these secondary metabolites when compared to their wild cousins. From that perspective, one could argue that most Westerners probably don’t eat enough plant toxins these days.
There’s even a new paper out that suggests that hominids co-evolved with entire plant communities that specifically adapted to humans.
Gut flora also play a role in detoxification. Certainly there are many with wrecked modern guts who can’t even handle cooked domesticated potatoes. One might suspect the ancestors of indigenous tribesmen would be unimpressed at our weak modern guts.
The problem with the “avoid all plant toxins” meme is that the entire narrative was perpetuated by various dietary authorities looking for a convenient way to make carbohydrates and plants look unappealing next to meat and fat. In reality, foods are complex and these toxins and anti-nutrients often have dual roles in our bodies. But in the eyes of many dietary authorities, all they had to do was isolate each ingredient and call each one “toxic” to scare people away from those foods. Fructose, lectins, you name it. And their narrative culminated in making everyone in Paleo™ orthorexic. Nobody noticed that these same compounds have many documented benefits.
Did those early hominids and indigenous cultures have it all wrong? Did the Egyptians get it wrong? No. More likely modern Paleo™ authors got excited about “anti-nutrients” and backed their almost exclusively low-carbohydrate narratives into some very rudimentary biochemistry that didn’t add up in the real world of wild plants. WAPF-friendly authors who didn’t consider dual roles of these compounds or hormesis, and didn’t want to look out of touch, promoted blanket anti-nutrient reduction techniques even though they only applied to certain situations (i.e., there is no tradition of diligently soaking legumes in Mexico, while there is a clear tradition of soaking maize).
As we showed above, scientists now believe the word “anti-nutrients” needs to be revised. Even the Wikipedia entry on tannins is hinting at this:
“Tannins have traditionally been considered antinutritional but it is now known that their beneficial or antinutritional properties depend upon their chemical structure and dosage.”
And there we go. The hand-wringing over anti-nutrients that have saturated the Paleo™ world is rather weak and unimpressive in the context of domesticated foods and nutrient-abundance. It’s time for people to wake up to the reality that hunter-gatherers gravitated towards low-toxin foods in the context of highly toxic wild plants. They utilized cooking to minimize toxins in the context of highly toxic wild plants. Over the past few thousand years, modern societies have hybridized plants down to a weak version of their wild cousins. Plants of the Solanaceae family (nightshades) were traditionally used as medicinals, but today we enjoy tomatoes and Yukon gold potatoes that have negligible/hormetic amounts of toxins in them.
We sleep in cushy beds, in warm houses and we take hot showers. We now consume far less toxins and expose ourselves to far less stressors than our hunter-gatherer ancestors did. Our honeys are tested for toxins, our plants are cooked to death (the Hadza barely cooked theirs).
It’s no wonder that those with the weakest guts tend to gravitate towards modern low toxin Paleo™ diets. The inability to handle weak domesticated plant toxins in cooked foods is almost certainly due to a modern disruption of toxin-clearing gut flora.
Obviously this is a controversial topic in the Paleo™ world, but when we look at the habits of indigenous cultures and the observed benefits from these compounds, it’s difficult to buy into the anti-nutrient meme anymore, within the context of hybridized domesticated foods. Traditional preparations are a good blueprint, but it makes sense for people to actually follow the actual traditions (sourdough baguettes, or unsoaked Mexican beans) rather than to simply assume that all toxins are verboten and poisonous.
…Incidentally, herbs and spices are one of the few plants you can easily obtain that are fairly close to their wild varieties. It’s fairly impossible to overindulge in herbs/spices—they often taste too bitter or hot. Herbs and spices are pretty toxic, but they are well known to provide health benefits when used in tolerable amounts. Go figure.
[If anyone has contact with Arthur Haines, please alert him to this. We’d love his critique, perhaps added input.]
Update: Botanist Arthur Haines has offered his input/critique in this comment. I think it’s a great juxtaposition. Whereas Arthur comes from a grounded perspective of how to use wild plants while mitigating toxins to hormetic or medicinal purposes, towards true natural vitality, The Duck Dodgers come from a perspective where supposedly, “”paleo” makes you strong through the almost complete avoidance of even the most dilute “toxic” load contained in domesticated plants—that must be protected by pesticides and other technological measures because they’re so defenseless against nature itself.