Cyanide is natural, Aspirin is synthetic. Which one do you trust?
Natural doesn’t mean safe and synthetic doesn’t mean harmful—the appeal to nature fallacy convinces you otherwise.
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We are back at it with the next edition of Fundamental Elements, a new section of ImmunoLogic. The goal? Break down science basics, address logical fallacies, and improve critical thinking, so that you are better equipped to navigate the misinformation minefield that our society is living in.
There is a logical progression in topics—think of it as following a course syllabus.
We can’t discuss more complex topics if we are at different places in our science understanding. If you missed the last piece, I highly recommend you read that one first, as today’s will build on that.
If you spend any time on social media or even on legacy media, you’ve seen the posts:
Beware the “toxic chemicals” in your foods
Watch out for the “toxins” in your skincare products
Even your gym clothes are filled with carcinogens!
Vaccines are filled with toxic chemicals
GMOs and conventional pesticides are laden with toxins
The villain in these claims? Synthetic chemicals.
At the same time, the people circulating these messages are promoting alternative “natural” products—that they claim are safer, healthier, beneficial, and even more eco-friendly—because they are trying to convince you that modern science and tools developed by it are evil.
The belief that “natural” is inherently better than “synthetic” is false — and it’s called the appeal to nature fallacy.
The appeal to nature fallacy convinces people that things (chemicals, substances, organisms) that are “natural” are better, good, beneficial, right, or safer simply because they are 'natural'.
The opposite extends to anything “unnatural” — synthetic or artificial substances. People who fall prey to this believe that synthetic substances are inherently bad, harmful, dangerous, inferior, and unsafe.
The reality? Natural doesn’t mean safe, and synthetic doesn’t mean dangerous.
This appeal to nature fallacy is closely tied with chemophobia—the irrational fear of chemicals—which is a central theme in wellness disinformation and anti-science rhetoric and policy (more can be found about this in the main newsletter section!)
This plays on your emotions too: you are made to FEEL that natural is better, so you’ll be more likely to believe claims supporting this idea, even if it is entirely false.
But remember: everything is chemicals.
Your body? Chemicals. Your food? Chemicals (yes, even the “all natural” flavors and food dyes—all chemicals). Those unregulated dietary supplements? Chemicals.
That “chemical-free” soap? Marketing nonsense intended to scare you.
There’s no such thing as “chemical-free” — but these messages try to suggest that there is a difference between naturally occurring chemicals (from plants, animals, and the Earth) and synthetic chemicals (made or modified in a lab).
Does that difference matter? No.
The source of a chemical—whether derived from nature or synthesized in a laboratory—has no impact on whether it is safe or beneficial.
The potential harms (or benefits) of a chemical is entirely dependent on the chemical itself.
Some of the most dangerous substances on the planet come from nature.
People assume synthetic chemicals are more toxic than natural ones because of rhetoric that has been ingrained into their minds for years and years. This is entirely false, but let’s use some examples.
Lots of natural chemicals can kill you at low doses.
With everything, the dose makes the poison. That’s true for natural chemicals or synthetic ones. They are all still chemicals, and plenty of natural things have high toxicity. (For reference: one-quarter teaspoon of granulated sugar weighs about 1 gram)
Arsenic is a naturally occurring element found throughout our environment in soils, sediments (rocks and minerals), and in our groundwater. Arsenic trioxide is formed when arsenic in these natural sources combines with air (another chemical). Arsenic trioxide is readily absorbed in the digestive tract, and can be fatal if ingested at a dose of 0.002 grams per kilogram, meaning a 70 kg adult (154 lbs) can die if they ingest 0.1 grams of arsenic trioxide.
Botulinum toxin is a protein toxin produced by the bacteria Clostridium botulinum (all natural!). Colloquially referred to as “Botox”, Botulinum toxin is a neurotoxin, as the protein interferes with nerve function. It causes muscle weakness, lack of muscle contraction, and flaccid paralysis.
Botulinum toxin causes Botulism. The illness is not caused by the bacteria Clostridium botulinum itself, but that toxin it produces. A dose of Botulinum toxin as low as 0.000001 grams per kilogram, if ingested, can be fatal. A 70 kg adult would only need to consume 70 micrograms (0.00007 g) of this natural protein to die. This is how Botulism is fatal - through ingesting food products contaminated with Clostridium botulinum that has produced toxin.
Purified Botulinum toxin is used cosmetically and medically for chronic migraines, colorectal surgeries, esophageal procedures, overactive bladder, hyperhidrosis (excessive sweating), and more. These involve targeted and controlled injection of Botulinum toxin.
Copper sulfate is a naturally-occurring chemical found ubiquitously throughout our planet and is used as a pesticide in organic farming. Copper sulfate can be fatal to humans if ingested at 0.011 grams per kilogram. That 70 kg (154 lb) adult? 0.77 grams of copper sulfate can cause acute toxicity and death. (Yes, organic farming uses a lot of pesticides, and they are not “better” —that’s just the appeal to nature fallacy talking!)
Countless chemicals produced by plants are extremely toxic at low doses. It’s evolution. Plants can’t actively fight off predators, so they produce chemicals to deter them.
The rosary pea or jequirity bean is a flowering plant native to Asia and Australia, Abrus precatorius. These brightly colored seeds contain a chemical called abrin. Abrin is a protein that consists of 2 subunits, and is a potent toxin. Abrin can be toxic through ingestion, inhalation, intravenously, and topically. Abrin can be fatal if ingested at 10-1000 μg/kg if ingested and even lower dosage if inhaled. A single seed chewed (not even swallowed as abrin simply needs to be released and swallowed in saliva) can kill someone.
You’ve heard of ricin, right? That’s another natural toxin, that’s produced by the castor bean. It’s fatal if ingested at 1 milligram per kilogram of body weight. Abrin is 100 times more toxic than ricin, for comparison.
Cyanide is natural too! In fact, chemicals produced by plants called cyanogenic glycosides are converted into hydrogen cyanide, which can be fatal to humans if ingested at 1 mg per kg body weight. The good news? If you’re a 70 kg adult, that’s the amount you’d ingest by eating 40 apples worth of seeds.
Other natural things? Snake venom. Every pathogenic microorganism that causes disease. Bears. Asbestos. Radiation. Poisonous mushrooms. Tetrodotoxin (that’s the puffer fish toxin). Box jellyfish venom.
Isn’t nature fun?!
Our body doesn’t know—or care—whether a chemical is synthetic or natural.
How we interact with chemicals is completely irrespective of the source of a chemical. Our body doesn’t know whether the chemical was isolated from a natural substance or whether it was synthesized entirely in a lab. The things that matter are the dosage of the chemical, the route of exposure of the chemical, and the chemical nature of the chemical.
And that is particularly true when we are looking at the same chemical.
Naturally-derived and synthetic versions of a chemical are exactly the same chemical.
Vitamin C, chemical formula C₆H₈O₆, also know, as ascorbic acid, scientifically called (5R)-[(1S)-1,2-Dihydroxyethyl]-3,4-dihydroxyfuran-2(5H)-one is found in a variety of plants including citrus, broccoli, cabbage, brussels sprouts, bell peppers, guava, etc.
Vitamin C can be extracted from these foods or synthesized in the lab (using a chemical reaction called the Reichstein process, where bacteria or yeast ferment glucose to make ascorbic acid). Guess what? That vitamin C is exactly the same.
Let’s take another example that is relevant to recent public discourse: formaldehyde, formula CH₂O.
Formaldehyde is sometimes used to inactivate viruses or toxins in vaccine manufacturing. The trace amount of formaldehyde that might be in a finished vaccine is less <50 µg per dose.
An adult produces 1.5 ounces of formaldehyde daily during our normal metabolic processes (42,520,000 micrograms (µg), in case you’re wondering. 850,000-times more formaldehyde every day than what might be a residual in a vaccine).
We also maintain levels of formaldehyde in our blood at all times, ~2.5 µg per mL of blood volume. Any extra, from any source, is rapidly excreted in urine.
A 2-month old infant has roughly 1.1 milligrams (1,100 µg) of formaldehyde in their blood at any point in time from their metabolism. That’s more than 22 times the maximum residual level of formaldehyde that might be in a vaccine, if applicable.
When this information is presented to people, often they respond with: “well, natural formaldehyde is different than the formaldehyde in a vaccine.” This is wrong.
Formaldehyde is the same exact chemical whether it is produced by you or whether it comes out of a bottle in a laboratory.
There is no such thing as “natural formaldehyde” and “synthetic formaldehyde” in the context of how your body responds to it. If the chemical name is formaldehyde, that’s what it is.
Did you know that natural and artificial flavorings are also the same chemicals?
This one might blow your mind, but it’s important to discuss since the current HHS Secretary is going all in on spreading unfounded fear of chemicals in foods, medicines, and more.
When you read a food label and you see “natural butter flavoring” or “artificial butter flavoring” — you might be inclined to seek out the one that says natural, right? That’s the appeal to nature fallacy, again. It’s not your fault, it’s been a concerted effort to undermine science and scare people for decades.
But in the context of flavorings, they are actually the same combinations of chemicals. What determines whether it is labeled as natural or artificial is determined by the starting materials.
Butter flavor in food is characterized by 2 primary chemicals, 2,3-butanedione and 3-hydroxy-2-butanone. They can be produced in 2 main ways: the biotechnological (natural) way or through chemical synthesis.
The biotechnological way simulates how butter gets its flavor normally: taking dairy products—specifically the glucose in them—and allowing added bacteria (usually species like Bacillus subtilis or Klebsiella pneumoniae) to ferment them into those chemicals.
The chemical synthesis method merely uses other chemicals in chemical reactions to produce those chemicals
The end result? The same chemicals. So while the appeal to nature fallacy is telling your brain “natural flavorings” are superior, in this case, they’re exactly the same chemicals.
Countless synthetic substances are not only safe at similar doses, but beneficial.
Vaccinations. Antibiotics. Pharmaceutical medications. Medical devices. Computers. Antiseptics. Conventional pesticides.
Many of these things were derived from something found in nature, but were improved upon using our knowledge and scientific technologies.
Aspirin, (acetylsalicylic acid), is related to a chemical in willow bark, salicin.
Salicin is converted into salicylic acid, both of which have therapeutic properties, but high doses are required. At those doses, undesirable side effects appear: stomach cramping, stomach bleeding, diarrhea, vomiting, heartburn. Fun! Scientists made a more potent and better tolerated version: aspirin. Aspirin exerts pain-relieving and anti-inflammatory effects at far lower dosages than natural relatives with far fewer potential side effects.
Contrast with another related chemical, methyl salicylate, naturally produced by wintergreen plants. It’s promoted as a natural alternative to aspirin (primarily for topical use), but it is 4 times more toxic than the synthetic salicylate in aspirin. If you ingest even a tablespoon of the concentrated oil, it can be fatal.
Vaccinations are synthetic “versions” of pathogens that protect against potentially fatal illnesses without the risk of disease.
Natural immunity is NOT superior to vaccine-induced immunity: infection comes with risk of illness, long-term complications, and death.
Synthetic pesticides used in conventional farming are often adapted from natural pesticides that are used in organic farming.
These alterations improve the stability, specificity, and efficacy of the chemical in question, so farmers can apply less with reduced ecological impact. Pyrethroids are synthetic derivatives of pyrethrins, produced by the Chrysanthemum cinerariaefolium plant that work as insecticides. Pyrethrins degrade rapidly when extracted and exposed to sunlight, so they need to be applied frequently to combat insect pests. Pyrethroids have been synthetically altered to be more stable and consistent, allowing farmers to use less pesticides for the same result.
Think like a scientist when you hear claims about chemicals
The next time you see headlines like: “Toxic chemicals in your shampoo!” or “The dangerous food additives Big Food doesn’t want you to know about!” remember: these headlines are exploiting the appeal to nature fallacy to scare people.
Before you fall into the fearfluencer trap, ask yourself:
What does the science say about this chemical?
Is there actual evidence of harm at realistic exposures?
What’s the dose? Everything is toxic at high enough levels, even water.
Is the alternative actually safer, or is it a marketing ploy?
There is no reason to automatically fear synthetic substances OR automatically trust natural substances.
Synthetic chemicals are not inherently harmful. Often, they’re safer and more effective than their natural counterparts. Nature doesn’t care about your feelings—many natural chemicals can cause far more harm than anything made in a lab.
Arsenic is natural, and so is lead. Life-saving medications like insulin are synthetic. Which would you rather have?
Science isn’t scary, but misinformation makes it seem that way. We are going to fix that.
Now, more than ever, we all must join in the fight for science.
Thank you for supporting evidence-based science communication. With outbreaks of preventable diseases, refusal of evidence-based medical interventions, propagation of pseudoscience by prominent public “personalities”, it’s needed now more than ever.
More science education, less disinformation.
- Andrea
ImmunoLogic is written by Dr. Andrea Love, PhD - immunologist and microbiologist. She works full-time in life sciences biotech and has had a lifelong passion for closing the science literacy gap and combating pseudoscience and health misinformation as far back as her childhood. This newsletter and her science communication on her social media pages are born from that passion. Follow on Instagram, Threads, Twitter, and Facebook, or support the newsletter by subscribing below:
Thank you for the time and effort you put into these posts, Dr. Love. I appreciate your work.
Another thing to mention is how incredibly inefficient it can be to isolate natural chemicals. One of the main drivers in my field of chemistry is to devise a synthetic route to a natural product, because the extraction from nature requires tedious (copious amounts of solvents) and sometimes expensive purification techniques (chromatography). Synthetic chemistry has come a long way in optimizing the efficiency of isolation and also decrease the amount of waste products generated from those processes.