The Quiet Lie of the Word Natural

A child wanders into the back garden in late summer. The berries on the low shrub are dark and glossy, almost black, sweet enough that she swallows two before her mother sees. The plant has no warning sign. It was not sprayed. It grew, as the marketing copy on so many bottles likes to say, untouched. By the time she reaches the emergency room, her pupils are dilated to the edges of her irises and her heart is racing past 180. The plant was Atropa belladonna, deadly nightshade, a species that has been killing curious children in temperate gardens for several thousand years. It is entirely natural. It is also, gram for gram, more dangerous than most things a person could buy from a chemist.

This is the trouble with a word. Natural has become, over the past four decades, one of the most powerful adjectives in the consumer economy. It appears on roughly six in ten new food products launched in the United States. It anchors a global herbal supplement market that now exceeds 230 billion dollars annually ¹. It implies, without quite saying so, that whatever it modifies is gentle, ancient, trustworthy, and free from the corruption of modern industry. And yet the United States Food and Drug Administration has no formal regulatory definition of the term. None. In 2016, the agency opened a public comment period to ask what natural ought to mean on a food label. More than 7,600 responses arrived. Almost a decade later, the matter remains unresolved ².

The gap between the word and its meaning is wider than most shoppers realize. Nature, considered honestly, is not a gentle pharmacy. It is the oldest chemist alive, and it did not evolve its molecules with human welfare in mind.

The Brussels Clinic

In 1992, a weight-loss clinic in Brussels made a small substitution to one of its herbal formulas. The clinic offered a regimen that combined appetite suppressants with a mixture of Chinese herbs, marketed as a softer, more holistic accompaniment to the pharmaceutical core of the program. One of those herbs, Stephania tetrandra, was difficult to source that year. The supplier swapped in a plant with a similar Chinese name and a similar appearance: Aristolochia fangchi. To a clerk in a warehouse the substitution looked like nothing. To a kidney, it was catastrophic.

Within months, young women who had been otherwise healthy began arriving at Belgian hospitals with rapidly progressing renal failure. Dr. Jean-Louis Vanherweghem, a nephrologist at the Erasme Hospital, identified a cluster of cases and traced them to the clinic ³. The condition was eventually named aristolochic acid nephropathy. By the time the link was confirmed, more than a hundred patients had been affected. Many required transplants. A significant fraction went on to develop urothelial cancer years later, because aristolochic acid is not only a kidney toxin. It is one of the most potent human carcinogens ever measured, forming DNA adducts at remarkably low doses ⁴.

The troubling part is not the substitution. Substitutions happen in any supply chain. The troubling part is that Aristolochia itself had been used in traditional medicine for roughly two thousand years. It appears in ancient Greek pharmacopoeia, in classical Chinese formularies, in folk remedies across Europe and the Americas. The plant grows wild on every inhabited continent. Subsequent epidemiology has linked it to longstanding clusters of kidney disease and upper urinary tract cancer in rural Taiwan and along the Danube in the Balkans, where local wheat harvests are sometimes contaminated with Aristolochia seeds ⁵. The plant was not corrupted by modernity. It was doing, with admirable efficiency, exactly what it had evolved to do for half a million years before any human picked it.

What a Plant Is For

It helps to remember that a plant is a chemical factory under siege. It cannot run from the insect chewing its leaves or the deer browsing its shoots. Its only available defense is biochemistry. Over hundreds of millions of years of coevolution with herbivores, plants have refined a pharmacological arsenal that exists for one reason: to make eating them unpleasant, painful, or fatal. The interesting accidents of this arsenal, the molecules that happen to interact usefully with the human nervous system or immune system, are what we call medicines. The other molecules, which are most of them, are simply poisons.

Cassava, the starchy root that feeds roughly 800 million people across the tropics, produces cyanogenic glycosides that release hydrogen cyanide when the plant tissue is crushed or chewed. Communities that depend on cassava have developed elaborate processing rituals, soaking, fermenting, sun-drying, grating, that detoxify the root over several days. Where those rituals break down, usually during droughts and conflicts, a paralytic disorder called konzo appears in epidemic clusters ⁶. Children are the most common victims.

Raw kidney beans contain phytohemagglutinin, a lectin so reactive that as few as four or five undercooked beans can send an adult to the hospital with violent gastrointestinal distress. Apple seeds, peach pits, bitter almonds, and the leaves of elderberries all hold cyanide precursors. Nutmeg, in quantities only slightly larger than a baker uses in a custard, can produce delirium, hallucinations, and seizures, an effect known since the seventeenth century and rediscovered periodically by teenagers searching the internet for legal highs. Even rhubarb leaves, attached to the same stalks we stew into pies, contain enough oxalic acid to be unsafe in any meaningful quantity.

None of these foods are contaminated. They are, in the strictest sense, pure. Their chemistry is the chemistry of survival, written by evolutionary pressures that never accounted for the question of whether a person could safely eat them.

The Tea Aisle

The danger does not stay in the wild. It walks into ordinary grocery stores carrying ordinary labels.

Comfrey, a leafy perennial with purple bell-shaped flowers, was sold for most of the twentieth century as a soothing tonic for joints, digestion, and bone healing. It appeared in herbal teas, salves, capsules, and tinctures. Comfrey contains pyrrolizidine alkaloids, a class of compounds that the liver converts into reactive intermediates capable of destroying hepatic tissue and inducing veno-occlusive disease, a condition in which small blood vessels in the liver scar shut. After several documented cases of liver failure linked to oral comfrey, the FDA in 2001 asked manufacturers to remove ingestible comfrey products from the American market ⁷. Topical preparations remain on shelves.

Kava, the root that Pacific Islanders have brewed into a ceremonial drink for centuries, became a popular Western anxiolytic in the 1990s. By 2002, regulators in Germany, Switzerland, and several other European nations had restricted or banned kava products following reports of severe hepatotoxicity, including transplant-requiring liver failure ⁸. The mechanism is still debated. Some researchers point to the ethanol or acetone extraction methods used in Western preparations, which concentrate compounds the traditional water-based brew leaves behind. Others suspect the substitution of kava cultivars not historically used for consumption. Either way, the plant that islanders had safely consumed for a thousand years produced, in its industrialized form, a public health crisis.

The pattern recurs. Ephedra sinica, the Chinese herb known as ma huang, has been used in traditional medicine for asthma and respiratory complaints for at least two millennia. In the 1990s, American supplement manufacturers extracted its active alkaloid, ephedrine, and combined it with caffeine in products marketed for weight loss and athletic performance. By the early 2000s, the FDA had received reports of more than 155 deaths and thousands of adverse events associated with ephedra-containing supplements, including heart attacks, strokes, and sudden cardiac arrest in young, otherwise healthy users ⁹. In February 2003, Steve Bechler, a 23-year-old pitcher in the Baltimore Orioles organization, collapsed at spring training in Florida and died of heatstroke compounded by ephedra use. The bottle in his locker advertised all-natural energy. The FDA banned ephedra-containing supplements in 2004.

A Law That Changed the Shelf

To understand how products like ephedra came to sit beside multivitamins on American shelves, the date that matters is October 25, 1994. That was the day the Dietary Supplement Health and Education Act, known as DSHEA, became law. The legislation, championed by Senators Orrin Hatch and Tom Harkin and shaped substantially by the supplement industry, reclassified dietary supplements as a category distinct from drugs. Under DSHEA, manufacturers do not need to demonstrate the safety or efficacy of a supplement before selling it. The burden of proof inverted. The FDA must show, after a product is already on the market, that it presents a significant risk of harm. In practice, that often means waiting for adverse event reports, hospitalizations, and deaths to accumulate before action becomes possible ¹⁰.

Dr. Paul Offit, a pediatrician at the Children’s Hospital of Philadelphia and the author of Do You Believe in Magic?, has spent much of the last decade documenting what this regulatory architecture has cost. His tally includes liver injuries from green tea extracts, cardiac events from bitter orange, hemorrhagic strokes from ginkgo combined with anticoagulants, and a long list of cases in which patients arrived in emergency rooms unable to tell their physicians what they had taken because the label gave only proprietary blends and Latin names ¹¹.

The label, it turns out, may not even describe what is in the bottle. In 2015, the office of the New York State attorney general commissioned DNA barcoding tests on store-brand herbal supplements sold at four major American retailers. The results were striking. Roughly four in five products tested contained none of the herbs advertised on the label. Many contained fillers and substitutes: powdered rice, house plants, asparagus, wheat, soy, undeclared allergens. A bottle labeled ginkgo biloba might contain no ginkgo at all ¹². The findings were contested by some industry representatives, who argued the testing methodology was poorly suited to processed extracts. But the broader picture, that the supplement aisle is a market in which buyers cannot independently verify what they are buying, has been confirmed by subsequent investigations.

The Dose, and Only the Dose

The sixteenth-century Swiss physician known as Paracelsus left behind one of the few aphorisms in medicine that has survived five hundred years of revision without losing its force. Sola dosis facit venenum. Only the dose makes the poison. He wrote it in 1538, in the context of arguing that any substance, however benign, becomes toxic at a sufficient quantity, and any toxin, however fearsome, has a threshold below which it does no harm ¹³. The principle is the foundation of modern toxicology. It is also the most efficient solvent for the marketing word natural ever devised.

Water, consumed in great enough quantity in a short enough time, can kill a healthy adult by diluting blood sodium to the point of cerebral edema. Marathon runners have died this way. Oxygen, the gas without which no human cell can function, damages lung tissue at concentrations above 50 percent for sustained periods. Botulinum toxin, produced by Clostridium botulinum bacteria growing happily in nature, is the most lethal substance per gram ever measured, and it is also injected, in pharmaceutical microdoses, into the foreheads of millions. Arsenic occurs naturally in groundwater across South Asia and the American Southwest. The venom of a single geographic cone snail contains enough conotoxins to kill more than a dozen adults, and pharmaceutical chemists have spent decades trying to extract from it a new class of painkillers.

The molecule does not know where it came from. A serotonin reuptake inhibitor synthesized in a New Jersey laboratory and a serotonin reuptake inhibitor extracted from a plant root behave identically in the bloodstream because they are, in any biochemically meaningful sense, the same compound. A toxin produced by a fungus and a toxin produced by a chemist work by the same mechanism on the same receptors. The label natural applies to provenance, not to pharmacology. It tells the consumer about the supply chain, not about the dose, not about the interaction with other drugs, not about the manufacturing consistency, not about whether the bottle in question contains what the bottle says it contains.

This is the quiet substitution at the heart of the modern wellness industry. A word that means originating in nature, which is a statement of geography, has been allowed to mean safe for human consumption, which is a statement of pharmacology. The two have nothing necessary to do with one another. They overlap in some products and diverge sharply in others, and the consumer, given only the label, has no way of telling which is which.

What the Label Cannot Tell You

None of this is an argument against plants, or against tradition, or against the long human practice of finding medicine in the things that grow. Aspirin came from willow bark. Digitalis came from foxglove. Artemisinin, which has saved millions of lives from malaria, came from a herb that Chinese physicians have used since the fourth century. The pharmacy of nature is real and extraordinary, and the careful study of it remains one of the more productive frontiers of medicine. The argument is narrower. It is against the conflation of natural with safe, and against the regulatory and commercial structures that have allowed that conflation to flourish.

A more useful pair of words might be tested and characterized. A substance that has been tested, in adequate doses, in adequate numbers of human subjects, across adequate durations, by parties without a financial interest in the outcome, is a substance about which something useful can be said. A substance that has been characterized, meaning its active compounds are identified, its concentration is consistent from batch to batch, and its interactions with other medications are documented, is a substance a physician can responsibly recommend. These conditions can be met by a synthetic pharmaceutical or by an herbal extract. They are not properties of origin. They are properties of evidence.

The practical implications are unglamorous. A shopper considering a supplement might ask whether the manufacturer participates in any third-party verification program, such as the United States Pharmacopeia or NSF International, which test for label accuracy and contamination. A patient considering an herbal remedy might mention it to a pharmacist, who can check for interactions with prescription drugs. A parent letting a child taste an unfamiliar berry might, despite the inconvenience, identify the plant first. None of these habits are exciting. They are the small, patient practices of treating the body as if its chemistry mattered.

Natural to Whom

Return to the berry in the backyard. It was natural in the sense that it grew without human assistance, and natural in the sense that humans had nothing to do with the molecules it contained. It was also natural, in a deeper sense, to the moth whose larvae had coevolved to digest it, and to the bird whose digestive tract passed its seeds intact. It was not natural to the toddler. The toddler was a relatively recent arrival in the evolutionary history of Atropa belladonna, and the plant had made no accommodation for her.

The word, in the end, is a question of frame. Natural to whom, and for what purpose, and at what dose, and prepared in what way, and combined with what else. The marketing economy has stripped these qualifiers and sold the remainder as a kind of moral assurance. The pharmacology, which does not read labels, continues to behave as it always has. Somewhere between the two, a thoughtful reader can stand. Read the ingredient list. Ask what the dose is. Ask who studied it, and where the study was published, and whether anyone replicated it. Treat the bottle with the same skepticism a careful person brings to any other commercial promise.

Nature is not the enemy. Nor is it a kind, maternal pharmacy waiting to forgive what modern medicine has gotten wrong. It is, and has always been, an indifferent chemist working on problems other than ours. The least we can do, in return, is read carefully.

Sources

1. Negowetti, N. E., ‘Defining Natural Foods: The Search for a Natural Law,’ Regulatory Studies, 2015. — https://www.law.uchicago.edu/files/file/regulatory_studies_negowetti.pdf
2. U.S. Food and Drug Administration, ‘Use of the Term Natural on Food Labeling.’ — https://www.fda.gov/food/food-labeling-nutrition/use-term-natural-food-labeling
3. Vanherweghem, J. L. et al., ‘Rapidly progressive interstitial renal fibrosis in young women: association with slimming regimen including Chinese herbs,’ The Lancet, 1993. — https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(93)90306-3/abstract
4. Grollman, A. P. et al., ‘Aristolochic acid and the etiology of endemic (Balkan) nephropathy,’ PNAS, 2007. — https://www.pnas.org/doi/10.1073/pnas.0701248104
5. Chen, C. H. et al., ‘Aristolochic acid-associated urothelial cancer in Taiwan,’ PNAS, 2012. — https://www.pnas.org/doi/10.1073/pnas.1119920109
6. Nzwalo, H. and Cliff, J., ‘Konzo: From Poverty, Cassava, and Cyanogen Intake to Toxico-Nutritional Neurological Disease,’ PLoS Neglected Tropical Diseases, 2011. — https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0001051
7. U.S. FDA, ‘FDA Advises Dietary Supplement Manufacturers to Remove Comfrey Products From the Market,’ 2001. — https://wayback.archive-it.org/7993/20171115051645/https://www.fda.gov/Food/DietarySupplements/ProductsIngredients/ucm111219.htm
8. Teschke, R., ‘Kava hepatotoxicity: pathogenetic aspects and prospective considerations,’ Liver International, 2010. — https://onlinelibrary.wiley.com/doi/10.1111/j.1478-3231.2010.02308.x
9. Haller, C. A. and Benowitz, N. L., ‘Adverse Cardiovascular and Central Nervous System Events Associated with Dietary Supplements Containing Ephedra Alkaloids,’ New England Journal of Medicine, 2000. — https://www.nejm.org/doi/full/10.1056/NEJM200012213432502
10. Cohen, P. A., ‘Hazards of Hindsight: Monitoring the Safety of Nutritional Supplements,’ New England Journal of Medicine, 2014. — https://www.nejm.org/doi/full/10.1056/NEJMp1315559
11. Offit, P. A., Do You Believe in Magic? The Sense and Nonsense of Alternative Medicine, HarperCollins, 2013. — https://www.harpercollins.com/products/do-you-believe-in-magic-paul-a-offit
12. O’Connor, A., ‘New York Attorney General Targets Supplements at Major Retailers,’ The New York Times, 2015. — https://well.blogs.nytimes.com/2015/02/03/new-york-attorney-general-targets-supplements-at-major-retailers/
13. Borzelleca, J. F., ‘Paracelsus: Herald of Modern Toxicology,’ Toxicological Sciences, 2000. — https://academic.oup.com/toxsci/article/53/1/2/1673334

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