Syndet Shampoo Bars and the Myth of “Natural”
We have received a few emails over the years asking whether we would ever make a “natural syndet shampoo bar.”
That question alone told me something important: many people don’t actually know what a syndet is — or why the phrase “natural syndet” doesn’t make sense.
The truth is simple: there is no such thing as a natural syndet bar.
What “Syndet” Really Means
Syndet is a blended word made by combining the words “synthetic” and "detergent."
A syndet bar is not soap. It’s a solid bar made from the same types of cleansing agents found in bottled shampoos, body washes, dish liquids, and laundry detergents.
To create any product that foams, lathers, and cleans — for hair, body, or even dishes — a surfactant (surface-active agent) is essential.
Surfactants lower the surface tension of water and bridge the gap between water and greasy dirt, allowing them to bind together so they can be easily rinsed away.
- Soap is a natural surfactant created by saponification.
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Detergents are a type of synthetic surfactant manufactured in a lab.
The term syndet refers to any cleansing product made with synthetic surfactants rather than true soap.
If your shampoo bar is labeled “soap-free,” it is a syndet made with synthetic detergents, even if it contains some plant oils, botanical extracts, or other natural ingredients.
If it’s marketed as “pH balanced,” it is almost certainly a syndet.
The word “syndet” simply sounds gentler than “synthetic detergent,” which is exactly why the industry prefers it.
📚 Learn More Blog: How Does Soap Work?
📚 Learn More Blog: The Chemistry of Natural Soap Making
A Bit of History of Syndets
Syndets were not created because they were gentler or more natural. They were created out of necessity.
During World War I, fats used for soapmaking were scarce, so chemists developed synthetic detergents as substitutes. One of the first was sodium lauryl sulfate (SLS), derived from lauryl alcohol isolated from coconut or palm kernel oil.
By the 1950s, syndets had overtaken soap in the U.S. market—driven largely by aggressive advertising on radio and television. One of the first syndet bars was Dove, introduced in 1955.
From that point on, synthetic detergents became the foundation of:
- liquid shampoos
- body washes
- facial cleansers
- dish soaps
- laundry detergents
So while the word “syndet” may be unfamiliar, the products are not.
📚 Learn More Blog: Sodium Lauryl Sulfate: What the Science Reveals
So, Why Are People Asking for Syndet Shampoo Bars?
Syndet shampoo bars didn’t emerge because of new hair science or superior skin biology. People aren’t asking for syndet shampoo bars because they’re natural — they’re not.
Syndet bars gained traction for two very practical reasons:
They reduce plastic waste
Many people want to cut down on plastic waste, and syndet bars look like an easy swap for bottled shampoo. They’re compact, travel-friendly, and eliminate plastic bottles.
If reducing plastic is your main goal, a syndet bar will absolutely do that.
They behave like bottled shampoo
Syndet shampoo bars feel familiar on the hair because they are familiar.
They are built on the same chemistry as liquid shampoos. They use the same type of synthetic detergents, often include fun fragrances and colors, and are designed to behave like a liquid shampoo.
They foam easily, rinse cleanly in hard water, and leave hair feeling the way conventional shampoo users expect—which makes the transition from liquid shampoo to a solid bar feel simpler, often with little adjustment needed.
In essence, they are concentrated liquid shampoos without the water or the plastic bottle.
For someone who has washed their hair with detergent-based liquid shampoo for years (or decades), this matters.
In short, syndet bars are popular not because they are more “natural,” but because they are a liquid shampoo in solid form—plastic-free and familiar.
But Are Syndet Bars Natural?
No. And this is where the confusion begins.
Many newer syndet shampoo bars — especially those marketed by more “natural” brands — have swapped older surfactants like sodium lauryl sulfate for alternatives such as sodium coco sulfate or sodium cocoyl isethionate.
Since these ingredients begin with coconut or palm oils, they’re often described as “natural surfactants” or “plant-derived.” But that language is misleading.
Terms like “plant-derived,” “naturally sourced,” or “derived from nature” suggest a close connection to the original plant, when in reality they only confirm that the ingredient started from a plant at some point in its life — not what it became.
They say nothing about how it was processed, how extensively it was chemically modified, or what was added along the way.
And because there are no legal definitions for these terms, they’re easy to stretch — even for brands that try to sound transparent.
There is a world of difference between a raw ingredient, like cold‑pressed coconut oil, and a “naturally derived” detergent.
Once that coconut goes through multiple rounds of chemical reactions, isolations, and transformations, the final ingredient can be just as synthetic as a detergent made from petroleum.
And while the word “natural” has become increasingly difficult to define, a shampoo bar made with highly processed synthetic detergents simply doesn’t align with what most people reasonably mean when they seek natural skincare
So yes — the detergents used in syndet bars can be derived from a natural source. But they are not natural.
And that’s fine — as long as people know what they’re choosing.
So… Which Shampoo Bar Should You Choose?
Before choosing a shampoo bar, it helps to be clear about your goals. Ask yourself one simple question:
Why do I want to switch to a shampoo bar?
If your priority is reducing plastic waste, keeping the familiar feel of bottled shampoo, and possibly avoiding any transition period, a soap-free syndet shampoo bar may be a good fit.
If your priority is reducing plastic waste and avoiding synthetic detergents, choosing minimally processed natural ingredients, and using a shampoo based on traditional soap chemistry with natural glycerin, a natural shampoo bar is the better match.
Neither choice is wrong.
But they are not the same.
The Bigger Picture
Syndet bars may be convenient and feel familiar, but they still rely on synthetic detergents.
Many also contain synthetic preservatives, fragrance compounds, and colorants—ingredients that can irritate the scalp or disrupt its natural balance.
And those synthetic chemicals don’t disappear after you rinse your hair.
They are washed down the drain, pass through wastewater systems, and eventually enter rivers, lakes, and oceans. While many are considered safe for short-term skin contact, their long-term effects on aquatic ecosystems are far less clear—especially given the enormous volume used every day worldwide.
For some people, choosing a true soap-based shampoo bar isn’t just about their hair or plastic—it’s also about reducing the amount of persistent synthetic chemistry released into the environment.
Plastic reduction is important. But it is only one piece of the environmental puzzle.
A natural shampoo bar behaves differently because it is different. It cleans without synthetic detergents. It retains natural glycerin. It respects the natural oils that protect the scalp.
And for many people, that difference is exactly what their hair—and their skin—needed.
Conclusion: An Informed Choice Matters
I’ll happily admit my bias: I own an organic skincare company, and I believe deeply in natural ingredients. But my goal isn’t to convince you that all synthetic surfactants are evil. It’s to help you make an informed choice.
Syndet bars are not natural. And they are not more “gentle” simply because they are marketed as pH-balanced. They are detergent-based shampoos in solid form—and that distinction matters.
So before choosing a shampoo bar, it’s worth asking yourself why you want one.
If reducing plastic waste is your main priority, you have many good options.
But if you are looking for a genuinely natural alternative to bottled shampoo—one that avoids synthetic detergents, preservatives, and other lab-made ingredients—then a syndet bar is not it.
Natural shampoo bars are different by design. They cleanse differently. They behave differently. And for many people, they support the scalp’s natural balance in a way that synthetic detergents do not.
A natural shampoo bar may require a brief adjustment period. But what it offers in return is something syndets never can: a cleanser built on simple chemistry, purposeful natural ingredients, and respect for how hair and scalp are designed to function.
Neither option is right for everyone.
But pretending they are the same does a disservice to consumers.
When you understand what syndets are, why they behave the way they do, and what true soap-based shampoo bars offer instead, you are no longer choosing based on trends or packaging claims.
You are choosing with clarity.
And for many people, that difference is not subtle.
It’s meaningful.
And sometimes, it’s transformative.
How We Make Natural Soap & Shampoo Bars
What is pH Balanced Skin Care?
Sodium Coco Sulfate: Is It Natural?
