Assuming that natural ingredients are always better than synthetic ones is a common error in judgment made by brands, influencers, and politicians.

Before writing this article, I visited a hair salon. As my stylist secured the smock around me, she pointed out the shampoo she intended to use. “This is a new brand featuring 90% natural ingredients,” she said. The pamphlet accompanying the products provided brief details on each item—one shampoo contained prickly pear extract, another had acai berries, and a third was formulated with chia seeds.

Upon returning home with my new shampoo, I scrutinized the ingredient list: Cetearyl alcohol, glycerin, behentrimonium chloride, isopropyl myristate. These are all standard, lab-created components, none of which caused me concern. Yet, none of these ingredients, which were present in greater amounts than many of the fruit extracts, were highlighted in the brand’s marketing materials.

The technique employed—successfully, in my case—is an age-old strategy. It is a common tactic on social media, utilized by brands and influencers and even politicians worldwide.

Often referred to as the “appeal to nature” or the “naturalistic fallacy,” this reasoning flaw ranks among the most frequently encountered logical fallacies. These fallacies can make a claim seem plausibly convincing. Whenever you hear assertions that a product or practice is better simply because it’s described as “natural,” or that something else is inferior due to being “unnatural,” you’re witnessing the naturalistic fallacy. Such claims often suggest that something is “as nature intended” or criticize it for being labeled a “chemical” or “synthetic.”

Nature is truly remarkable and teaches us many lessons. However, why is it inaccurate to claim that natural products are inherently superior?

For starters, nature lacks intentions in any conscious manner. As such, it does not set out to be beneficial for humanity.

We can avoid complicated philosophical debates to understand this; simply look at a few of nature’s creations. Arsenic, a substance that can be fatal in doses as small as 70mg, is completely natural. So too is asbestos, which has been linked to cancer. Cyanide, a phytotoxin found in over 2,000 plant species like almonds and peaches, can be lethal in minuscule quantities.

This illustrates why the term “natural” is misapplied to market various products. It is poorly defined and does not guarantee that a product branded as “natural” will be better or safer than other options.

An investigation into baby teething gels labeled as “natural” found that over 370 infants experienced harmful effects, such as seizures. These products were revealed to contain inconsistent and sometimes elevated levels of belladonna, known as deadly nightshade.

John Stuart Mill, in his 1874 essay “On Nature,” highlighted one major flaw in the use of “appeals to nature.” He questioned, “Should we embrace killing because nature does? Or should we refrain from considering nature’s actions and pursue what is genuinely good?” Essentially, if we accept that anything “natural” is better solely based on its nature, we must also be prepared to accept all of nature’s phenomena—or we likely do not truly believe that anything natural is inherently superior.

While it is easy to criticize human-made products, it’s essential to acknowledge the numerous advances that have improved lives significantly. Before modern healthcare, over one in every 100 women died during childbirth; in developed nations today, that statistic has improved to about one in 10,000. Furthermore, prior to widespread vaccination, whooping cough claimed one in every ten infected children’s lives. Post-vaccination, that number plummeted to approximately one in 157.

These advancements represent just medicine. Look around, and you’ll spot countless examples. While it may seem unnatural to wear glasses, keep food refrigerated, or turn on heating in winter, these practices most certainly provide better outcomes than the alternatives, such as living with poor vision, allowing perishables to spoil, or enduring the cold.

Most of our food does not arrive in its original form as nature intended—it undergoes processes like cooking and harvesting. The evolution of food preparation, from grinding grains to cultivating hybrid crops, transformed our society from nomadic hunters to settled agriculturalists, creating advanced civilizations. Today’s nutritious foods, such as the orange carrot or modern banana, look and taste drastically different from their wild ancestors.

While it’s important to recognize the challenges posed by manufactured products, like pollution from synthetic plastics, we must also understand that being “natural” does not inherently mean better. For instance, while carrots may be healthier than potato chips, it’s crucial to compare paracetamol with arsenic as well.

Another pressing issue with the “appeal to nature” is defining what constitutes as “natural.” Humans originate from nature. Thus, if every product of nature qualifies as “natural,” shouldn’t our actions be classified the same? Additionally, where do we place creations blending the conventional view of natural and artificial, like vaccines, which derive from natural viruses or bacteria to equip our immune systems against future infections?

“Nature” encompasses a myriad of meanings, as science historian Lorraine Daston remarks. Its interpretation varies based on context, which makes it a strategic choice for marketing—leading consumers to easily fall prey to its implications.

Moreover, even if we could effectively distinguish between human-made and natural, we might struggle to identify what is truly synthetic versus what is not.

Consider dental hygiene: is using fluoride toothpaste more unnatural than non-fluoride alternatives? Interestingly, fluoride is actually a mineral found in nature, while alternative substitutes like nano-hydroxyapatite are synthetic. Additionally, even the act of tooth brushing is a far cry from nature, as the closest primates come to dental care is using tools like feathers.

If I offered you a beverage composed of 99% dihydrogen monoxide, you might hesitate, since this chemical descriptor suggests a synthetic nature, but in fact, it’s simply water.

Therefore, the next time a product is promoted as “natural,” or someone critiques another product for being “unnatural,” take a moment to consider the underlying meaning. Furthermore, reflect on why the advocates of that product or practice resort to the “appeal to nature” fallacy instead of presenting logical arguments for its actual superiority.

* Amanda Ruggeri is a distinguished science and features journalist. She shares insights on expertise, media literacy, and more on Instagram at @mandyruggeri.

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