Shampoos, conditioners, and treatments have become indispensable in our daily lives. However, did you know that the chemical substances contained in them, called "surfactants," can have serious effects on our health?
In particular, cationic surfactants contained in treatments, rinses, fabric softeners, and deodorants pose risks that cannot be overlooked.
- What are surfactants?
- The effects of cationic surfactants on the body
- The Lethal Dose: LD50 and Cationic Surfactants
- Risks in everyday life: Long-term use of rinses and treatments
- The health benefits of going shampoo-free and skin fasting
- How to Practice: Start no shampoo and skin fasting
- Summary: To maintain a healthy body and beautiful hair
What are surfactants?
Surfactants are chemical substances that act to mix substances that do not normally mix, such as water and oil, and are used in a wide range of products, from shampoos and treatments to dishwashing detergents and cosmetics.
However, most people currently use these chemicals without knowing the adverse effects they can have on the body.
Types of Surfactants
There are four main types of surfactants:
From the Japan Surfactant Industry Association website
It would take too long to explain in detail here, so for more information please see the explanation page of the Japan Surfactant Industry Association .
Anionic surfactants and cationic surfactants are particularly involved in our daily lives.
Problems with strong anionic surfactants
The " anionic surfactants " contained in shampoo thoroughly remove dirt from hair and scalp, but their strong cleansing power destroys the scalp's barrier function, causing dryness and irritation . As a result, hair becomes more susceptible to static electricity, which makes it hard to wash after washing with shampoo alone.
Therefore, cationic surfactants are used to deal with this problem.
Why do we have to use chemical rinses and treatments after we have thoroughly washed our hair with shampoo? This is because rinses and treatments are the opposite of cationic surfactants, and they neutralize the hair and scalp to make them feel better.
However, it is these "cationic surfactants" that pose a great risk to the body.
The effects of cationic surfactants on the body
" Cationic surfactants " are used to reduce static electricity on hair and scalp, but they can actually have serious adverse effects on our bodies. Research by Professor Terry Hrubec of Virginia Tech University in the United States has revealed that these chemicals pose significant risks to human health.
Experiments show the risks of cationic surfactants
Professor Hrubec conducted a simple experiment: he changed the detergent used in the cages of rats in his research from an anionic surfactant to a cationic surfactant (quat) .
As a result, the surprising result was that the sperm count of male rats significantly decreased , and the number of ovulations in female rats was greatly reduced , resulting in a decline in the reproductive function of both . Furthermore, the offspring of rats that were born showed many deformities and developmental abnormalities , with the effects extending to the next generation.
Normally, such congenital abnormalities are rare in rat breeding, but in the environment where Quat was used, the effects extended to the next generation.
Even more surprising, exposing only males to the cationic surfactant increased the incidence of birth defects in subsequent generations, suggesting that the chemical may even affect genes .
Quat has such a powerful effect that it destroys cell membranes (which are made up of oil), making it prone to causing genetic abnormalities that can have serious effects on fertility and the health of offspring.
Comparison of anionic and cationic surfactants
Professor Hrubec's experiments have revealed that cationic surfactants pose far greater health risks than ordinary anionic surfactants. For example, the incidence of congenital abnormalities is only 0.1% when anionic surfactants are used, but when cationic surfactants are used, this figure rises 150 times higher to 15% .
As the results of this experiment show, the rinses, treatments, fabric softeners, and deodorants that we use every day without even thinking about them pose huge health risks.
In particular, the microbeads contained in recent fabric softeners use cationic surfactants to maintain a pleasant scent. Furthermore, since deodorants are neither cosmetics nor detergents, the government does not impose any standards on their usage, and there is no obligation to display the amount contained, making it unclear and ambiguous.
These are dangerous chemicals that households with small children or pets need to be extremely careful with.
Related Articles - The reality of chemical sensitivity and countermeasures - Lifestyle habits to protect your health
The Lethal Dose: LD50 and Cationic Surfactants
Another scary aspect of cationic surfactants is their LD50 (lethal dose).
LD50 is a measure of the amount of a chemical that will kill half of the animals.
In the case of anionic surfactants, which are found in ordinary shampoos and body washes, a lethal dose of about 2,700 mg per kg of body weight is reached. However, in the case of cationic surfactants (Quat), the lethal dose is only 50 mg . In other words, even 1/50th the amount of anionic surfactants can pose a life-threatening risk.
If we apply this to humans, it is suggested that for a person weighing 50 kg, ingesting just 2 to 10 g of Quat would be a risk of death for half of them . It's scary to imagine a household that sprinkles F*cklys every day in their home. It shows that it is a very powerful and dangerous chemical substance.
Risks in everyday life: Long-term use of rinses and treatments
Rinsing and treatments that we use every day contain a limited amount of Quat compared to fabric softeners and deodorants. But what would happen if you used it on your scalp every day?
Long-term use of this product can cause damage to cell membranes by coming into direct contact with the skin. Furthermore, if you wash your skin too much and it becomes dry, causing itching, and you scratch it, it is highly likely that this product will enter your body through your capillaries.
Furthermore, long-term use of these chemicals can lead to hormonal imbalances , reduced reproductive function , and even have effects at the genetic level.
Cosmetics also contain large amounts of surfactants . Hand soap and body soap are used to create foam, while lotions, serums, and creams are used to emulsify . It's scary how much surfactants are used in our daily lives.
From the Japan Surfactant Industry Association website
Risk of chemical sensitivity
In the past, there have been reports of an increase in the number of people who complained of allergic symptoms , difficulty breathing , fatigue, and headaches in households that used rinses, treatments, or fabric softeners. These are types of chemical sensitivity , and they can have serious effects on particularly sensitive people and small children, so caution is required.
The health benefits of going shampoo-free and skin fasting
As Professor Hrubec's research shows, the chemicals we use every day without even thinking about them pose huge risks. While the quats contained in rinses and treatments may provide temporary beauty benefits, they can cause serious damage to your health in the long term . To avoid these risks, the practice of going shampoo-free or skin fasting is now attracting attention.
What is no-shampoo?
De-shampooing is a method of washing the scalp and hair with just hot water and soap, without using chemicals such as shampoos, conditioners, or treatments, to restore the natural balance of sebum.
In fact, the benefits of not using shampoo are far greater than the benefits of avoiding exposure to the cationic surfactants contained in rinses and treatments, and freeing your hair and scalp from chemicals.
Benefits of Skin Fasting
Skin fasting is also a way to minimise the use of chemical products on the skin and boost the skin's natural ability to regenerate.
It promotes the skin's ability to heal itself without using excessive chemicals, so it is expected to have the effect of fundamentally resolving skin problems.
How to Practice: Start no shampoo and skin fasting
If you've read this article and are interested in trying going shampoo-free or skin fasting, you can get started right away. First, put the body mitten on both hands and gently wash your scalp and body with warm water. The specially manufactured organic cotton thread will remove excess sebum and dirt. We also recommend brushing your hair before use to remove some of the dirt.
For those with oily hair, scallop powder water is also effective. It is a strong alkaline water with a pH of 12, but it does not cause chemical burns, so you can use it with confidence. If your hair feels rough, spray it with citric acid water at the end and rinse it off to make it smooth!
Also, if you have pimples on your back caused by residual ingredients from the treatment, it is important to gently scrub the area with a body towel .
If possible, wash it without using any detergent and just with hot water. Organic cotton threads called Garabo, which were invented in the Meiji era, contain more air than regular threads and gently remove sebum stains.
How about these mini mittens for washing your face? They are small enough to fit three fingers (index finger, middle finger, and ring finger).
After use, wash it lightly with hot water and hang it in the bathroom, and it will dry very quickly. Please occasionally disinfect it by boiling it or wash it with scallop powder water.
It's easy to clean because it can reach all areas, including the wings of your nose and behind your ears. If you have simple makeup on, you can remove it with just warm water.
Summary: To maintain a healthy body and beautiful hair
The risks of surfactants contained in shampoos and conditioners are deeply related to our daily lives.
In order to protect your long-term health rather than being fixated on short-term beauty effects, it is important to adopt shampoo-free and skin fasting methods .
Little by little, you can free yourself from chemicals and have a healthier, cleaner body!
Addendum: (August 2, 2025)
Finally, I have developed my long-awaited shampoo bar for washing hair!
Botanical Shampoo Bar 60g Solid Shampoo Additive-Free Hokkaido Japanese Mint
For those who suffer from oily scalp and dandruff. This 60g botanical shampoo bar is cultivated in the natural environment of Hokkaido. Its pure soap ingredients, free of synthetic surfactants, gently remove dirt and promote a healthy scalp. The rare Japanese mint scent is refreshing. For use on hair and the entire body.
When I was living in Taiwan, I suffered from serious scalp problems.
Itching, dandruff, hair loss, rough skin, back acne...I was diagnosed with seborrheic dermatitis at a dermatologist and tried everything, including prescribed medications and shampoos that were effective on the scalp.
However, although there was a brief improvement, the condition soon worsened, and ultimately no fundamental solution was found.
Maybe the climate doesn't suit my constitution...
Maybe it's too much stress...
Changing my lifestyle didn't help at all, so after much trial and error I finally came across "hot water shampoo," a hair washing method that is completely free of chemicals.
The challenge of not using shampoo in Taiwan, where temperatures and humidity are high, was so tough that anyone with ordinary determination would have given up.
However, after six months, the symptoms finally improved.
Every time I share my experience, I get a huge response and learn that there are so many people out there who are suffering in the same way.
When I think back to the pain I felt at the time, I felt strongly that I could have resolved the issue in a more natural way.
So, with the help of SORRY KOUBOU and the power of plants produced in Hokkaido's rich natural environment, we began developing a shampoo bar that does not contain any chemical additives.
As we continued to use the prototype, we were able to accommodate our requests, including requests for more details and a texture like this.
They also worked hard to unearth rare ingredients, resulting in the creation of a soap with a wonderful scent and texture that far exceeded our imagination.
My own hair, which I usually wash with just hot water, has gradually changed since using this product.
The dirt in my pores was removed, my hair became thicker and more voluminous, and I no longer had to worry about the oxidized smell of excess sebum that would hit me in the evenings.
By the way, not only scalp problems, but also atopic dermatitis, rosacea, acne, itching, etc. For those who have problems around the chest, back, or face, the cause may actually be shampoo or treatment, or it may be making the problem worse! This is because it touches the body when rinsing.
There must be many more people with the same problem.
We hope you will find the solution with this shampoo bar made with this wonderful, rare ingredient.
These are my thoughts as someone involved in the development of this product.
So that's it!
If you are currently undergoing a skin fast or no shampoo regimen, we recommend trying this gentle botanical shampoo bar as a weekly treatment.
Related Article - Protect your sensitive skin in the summer! The truth about sunscreen and the complete guide to genuine UV protection skin care
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