The answer I found after battling scalp itching: The real way to improve seborrheic dermatitis from the root

Hello, I'm Miko, the manager of Kokaiko Shoten!

I'm sorry I haven't uploaded any YouTube videos for a long time. A lot of people have been asking me if I'm going to upload any yet, but I'll start filming once I've finished my work and feel like it, so please wait for a little while longer.

Well, today I'd like to tell you all about how I created our original botanical shampoo bar, which was released in August, and the causes I discovered through my past problems and efforts to improve them.

Well then, let's get started!

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.

A long battle with scalp problems that began in Taiwan

Fifteen years ago, I moved to Taiwan. Just three and a half years after moving, and two years after starting my own company and my days were incredibly busy, I gradually began to suffer from intense itching from my head to my neck, chest, and back. At first, I dismissed it as just the change in environment or being busy. However, the symptoms worsened day by day, and eventually the itching became so severe that it kept me up at night.

So I went to the hospital and was diagnosed with seborrheic dermatitis.

Using the prescribed antifungal and steroid medications certainly did improve the symptoms temporarily. However, once the medication was stopped, the symptoms would always return. This cycle continued for years. Having suffered from atopic dermatitis as a child, I knew firsthand the harmful effects of long-term steroid use. It weakened the immune system in the areas where the medication was applied, creating an environment in which bacteria could easily proliferate.

"If this continues, I'll be dependent on medication for the rest of my life."

Feeling this way, I began desperately searching for the cause. I changed my diet, tried to manage stress, and tried various scalp care products. The itching would subside, then get worse, but I left it for several years. Meanwhile, post-inflammatory hyperpigmentation developed around my neck and cleavage, where I had scratched the area, and I lived my life trying to hide the darkened skin.

Fed up with the situation, which had not improved despite years of relying on hospital medications and medicated shampoos, I began to dig into books written by Japanese dermatologists. In the process, I came across a book by Dr. Ryuichi Utsugi, and after practicing skin fasting and no shampoo, I was able to improve my condition. However, in the hot and humid climate of Taiwan, living without shampoo despite having seborrheic dermatitis was an unimaginable ordeal.

Then, two years ago, when I returned to Japan, I launched the cross-border e-commerce site "Xiao Guaoxiao Store" and, at the same time, decided to use my experience in Taiwan to take on the challenge of creating a product that could truly solve scalp problems .

Related ArticlesThe effects of skin fasting and seborrheic dermatitis improvement – Utsugi-style skin care and shampoo abstinence practice

　　　　　The challenge of going shampoo-free – how to break the addiction and get healthy hair back

Do you know the real cause of seborrheic dermatitis?

If you suffer from seborrheic dermatitis, you've probably heard of the name "Malassezia." The overgrowth of this fungus is said to cause dandruff, itching, and inflammation. However, there's an important fact to note here.

Malassezia is a normal fungus that is present on everyone's skin.

Malassezia, the bacteria that cause seborrheic dermatitis, is a normal skin flora, and just like the herpes virus, it cannot be completely killed. Even if it appears to have healed, it continues to live on the skin. Even if it clears up with antibiotics and steroids, you cannot let your guard down. It will start to grow again when your immune system weakens, and even if you can calm the current symptoms, the condition will recur.

In other words, the problem is not the fungus itself, but the environment in which it overgrows. On a healthy scalp, Malassezia plays a protective role by maintaining a balance with other resident fungi.

So why does the balance get lost?

What I realized during my time living in Taiwan is that the shampoo we use every day is the main culprit behind this destruction of the scalp environment !

The synthetic surfactants contained in most modern shampoos strip the scalp of its essential sebum, causing the scalp to sense the danger and begin to overproduce sebum to make up for the loss.

This excess sebum is the perfect food source for the Malassezia fungus. The fungus multiplies explosively and produces irritating substances as it breaks down the sebum. This causes dandruff, which further causes itching, and scratching further worsens the scalp environment. It's a vicious spiral.

Incidentally, many people with seborrheic dermatitis often use medicated shampoos that are quasi-drugs, but these shampoos simply contain a certain amount of active ingredients that relieve symptoms such as dandruff, itching, and dryness, and they also normally contain synthetic surfactants as cleansing ingredients.

Also, antifungal medications prescribed by doctors do indeed temporarily reduce Malassezia fungi. However, unless the underlying cause, "destruction of the scalp environment," is addressed, the condition will inevitably recur once the medication is stopped. Moreover, because the antifungal medication kills off all the other normal bacteria, the scalp environment is left in a state of ruin. The body secretes more and more sebum, and only the Malassezia fungi that survives there multiply, so it's obvious that the condition will only get worse.

And it's not just your scalp that's affected. When you rinse, the foam also comes into contact with your back, chest, and face. So, if you're suffering from itching or breakouts around your back, face, or chest, shampoo may be the culprit.

It took me a long time to realise this fact myself.

This is the area under my neck right after I started the skin fasting and no shampoo. I tried various medicines and it calmed down a bit, but the skin was always peeling and sore.

This photo was taken in 2019. After I started skin fasting and stopped using shampoo, the itchy scalp had subsided. However, as you can see, my back, which I had been scratching so much, had developed post-inflammatory hyperpigmentation and was completely dark.

This photo was taken today, August 20th, 2025.

The pigmentation hasn't completely disappeared, but it's gotten a lot better, and at least my skin has become whiter, so I can now fully expose my neck.

Somehow I overlooked it! The surprising effects of bathing

Also, after returning to Japan, I realized something: the importance of soaking in a bathtub every day .

Looking back, the first house I moved to after moving to Taiwan didn't have a bathtub, so I only had a shower. And I continued living without a bathtub in that house for six years. When I thought about it, ever since I was born, there wasn't a day that went by without a bath while I was in Japan. And I realized that this lack of bathing habits was one of the factors that worsened my scalp problems.

Japanese people are one of the few people in the world who loves bathing. However, in modern times, an increasing number of people are only taking showers due to their busy schedules. I believe this is actually the trigger for various health problems.

It's amazing how soaking in a hot bath can bring about amazing changes to your body. First of all, your body temperature inevitably rises when you soak in hot water. It's said that raising your basal body temperature by 1 degree can improve your immune system by 30%. The water pressure also pushes waste products that have accumulated in your calves upward, encouraging urination. At the same time, it improves lymphatic flow in the lower body, which tends to stagnate. Blood vessels expand, improving blood flow throughout the body, allowing sufficient nutrients and oxygen to reach your scalp.

Even more importantly, bathing induces sweating. Sweat expels harmful substances from the body and activates the sebaceous glands. This normalizes sebum secretion on the scalp and creates a healthy sebum film.

There is some interesting data. When cancer patients are asked about their lifestyle habits before they became ill, a large number of them respond that they were so busy that they only took showers and never bathed. A prolonged state of low body temperature weakens the immune system, and the stress of being busy can also lead to hypoxia, making people more susceptible to various illnesses.

Looking back, even during the four and a half years I spent living in Italy in my twenties, I only took showers. Even back then, I suffered from acne and rough skin, and I kept going to the local dermatologist and getting prescribed medicine. I also tried all kinds of doctor's cosmetics. "The water is hard, so it doesn't suit my skin," I thought at the time. But thinking about it, I think not taking baths was one of the reasons. Because when I returned to Japan, my problems were completely cured!

With this in mind, I made sure to take a bath every day after returning to Japan. As a result, since I contracted COVID-19 three months after returning to Japan, I haven't had a fever or caught a cold in the two years since, and although I've had some minor ailments, I've never been seriously ill.

Of course, improving my diet has had an effect, but my physical condition is clearly different from when I was in Italy or Taiwan.

The terrible things synthetic surfactants are doing to your scalp

Well, the main culprit that prolonged my seborrheic dermatitis was the synthetic surfactants contained in shampoos and treatments, but do you know what these synthetic surfactants are?

This is a chemical substance that mixes water and oil, and is used in most modern cleaning products, including shampoo, treatments, body soap, facial cleansers, and even cosmetic lotions and creams.

The scary thing about this substance is its incredibly powerful cleaning power.

It does remove dirt, but at the same time, it destroys the natural barrier function our bodies create.

The scalp naturally has an adequate sebum film. This is not just oil, but a natural protective barrier that protects the scalp from external stimuli, makes it easier for resident bacteria to live, prevents moisture evaporation, and blocks the invasion of harmful bacteria. Synthetic surfactants strip away this important sebum film.

Even more frightening is the accumulation in the body through percutaneous absorption. The scalp is one of the body's most absorbing areas, with an absorption rate about 3.5 times higher than the inside of the arm. Chemicals absorbed through daily shampooing can accumulate in the liver and kidneys, potentially causing serious health problems in the long term.

It has been reported that shampoo can disrupt hormone balance, weaken the immune system, and even affect reproductive function. When you think about your health 10 or 20 years from now, you need to reconsider the shampoo you use now.

However, there is actually a bigger problem with the treatments used after shampooing: they contain cationic surfactants.

This coats the hair and makes it smooth, but long-term use can destroy the cell membrane and weaken the hair roots. In exchange for smooth hair, we are destroying the very soil in which healthy hair grows. It would take too long to go into detail, so please read my blog about it.

Related ArticlesThe horror of surfactants! We recommend going shampoo-free and detoxifying your skin to avoid health risks

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Shampoo bar product development begins in search of a natural solution

So, while living in Taiwan, I decided to go on a skin fast and stop using shampoo. Doing this in Taiwan, where temperatures and humidity are high, was an unimaginable ordeal. My hair was sticky, my scalp smelled, and I was worried about the looks I got from others. I nearly gave up many times, but after about a year and a half, I finally made some progress.

Although I'm completely better now, when I think back to how difficult it was back then, I feel a strong desire to find a way to prevent more people from having to go through that same agony. While going without shampoo is certainly effective, it's just too difficult to put into practice while still living a normal social life.

When I returned to Japan two years ago and launched the cross-border e-commerce site "Kogaiko Shoten," a strong sense of mission emerged within me. When I shared videos about my experiences with skin fasting and going shampoo-free, I received an overwhelming response, and I realized that there were so many people who were suffering from the same skin diseases and scalp problems as me. I began to think, "If there are so many people with the same problems, I want to provide a more gentle solution!"

So, after researching and trying out various methods, we have come up with a method for washing your hair without shampoo using organic cotton towels and body towels and body mitts from the Cotton Series, made by Gara Boseki, a company with a long history in Japan.

Here it is.

Also, in this video, which recommends a detergent-free lifestyle and avoiding synthetic surfactants, I made a simple suggestion: put on the Cotton Series body mitts on both hands before washing!

Many people have expressed gratitude, saying that their scalps are now clean and easy to wash without shampoo. However, some have also said that the treatment doesn't improve their condition, that it's too painful, and that they can't stand the sebum smell that hits them in the afternoon, so they've gone back to using shampoo.

That's true. For me, going shampoo-free was a much tougher ordeal than I could have ever imagined. I thought that if someone was able to successfully go shampoo-free, then it probably meant that their condition hadn't become so severe.

Related Article - Skin Fasting and the Effects of Seborrheic Dermatitis Improvement – Utsugi-Style Skin Care and Shampoo Cessation Practice

No soap required. Garabo body mittens. 100% organic cotton. Traditional absorbency. Made in Japan.

For those concerned about surfactants. These body mittens are made using traditional Gara weaving. The air-filled, 100% organic cotton fibers absorb dead skin cells and sebum with just water. No soap is needed, making them gentle on the skin, and ideal for those who prefer to wash their hair with hot water. These handmade organic cotton products are packed with Japanese wisdom dating back to the Meiji era.

No soap required, Garabo body towel, 100% organic cotton, for sensitive skin, made in Japan

For those with sensitive skin who want to avoid surfactants and chemicals. This 100% organic cotton body towel uses the traditional Meiji era "Garabo" weaving technique. The unique fluffy fibers absorb sebum and dirt from pores using only water, reducing the burden caused by strong friction and preventing dryness from over-washing. Made in Japan, it can easily reach even men's backs.

A natural solution from the land of Hokkaido

It doesn't use chemicals, but it doesn't require extreme methods like going shampoo-free either. It's a product that uses the power of nature to effortlessly improve the scalp environment. I began to wonder if I could create that ideal shampoo...

So I decided to consult again with SORRY KOUBOU, a botanical skincare brand from Hokkaido that I always use.

To Mr. Yamada and Mr. Komatsu, the representatives of SORRY KOUBOU Co., Ltd., thank you for your continued support!

My hope was to create a shampoo bar that would use plants grown in the rich natural environment of Hokkaido, contain no chemical additives, be as gentle on the skin as possible, and lather well - a very difficult request, so I began development.

There, through an introduction from SORRY KOUBOU, I had a fateful encounter with the rare Japanese mint "JM-23", which is grown by only one farmer in Takinoue Town, Hokkaido.

In July of this year, I went to Hokkaido to see where the ingredients are produced, and was given a tour of the JM-23 farm.

Even before that, I had my eye on a Japanese mint variety called "Hokuto," which is also grown in Takinoue-cho, Hokkaido. The refreshingly sweet scent of this mint is like mint ice cream, and is gentler than the peppermint oil that is popular in Asia. So, we tried various ways to procure it for our store, but it was a rare ingredient and we were unable to purchase it at the time. Then, we were approached about this product, and it turns out that it is grown by the same farmer, so I remember feeling a strong connection.

In fact, from the Meiji period to the early Showa period, Hokkaido-grown mint accounted for 70% of the world market. Among them, the "JM-23" variety used in this blend boasted the highest quality. However, due to the enormous amount of work required to cultivate it, the difficulty of mechanizing it, and the difficulty of quality control, it is currently grown by only one farmer in the world.

The effect on my scalp was astonishing. It gently soothes itchiness, promotes blood circulation, and improves the scalp environment with its natural antibacterial properties. And it doesn't irritate my sensitive scalp. This was the ideal ingredient I had been looking for.

In addition, we have decided to include essential oil from Japanese Sakhalin fir (Todomatsu) produced in Shimokawa, Hokkaido.

Mr. Tanabe, the representative of Fupu no Mori Co., Ltd., who provided us with the essential oil from the raw material, Todo fir.Kameyama-san.thank you very much!

The essential oil extracted from Abies sachalinensis trees that have survived extreme cold of minus 30 degrees for over 100 years has been treasured by the Ainu people as a "blessing from the gods." It has a powerful effect of promoting blood circulation and anti-inflammatory properties, and can also be expected to have a relaxing effect through the forest bathing effect. It is also effective in combating body odor due to aging, making it a truly all-purpose essential oil.

We also paid particular attention to the manufacturing method. It is the "kettle cooking method" that has been used since the Edo period. This traditional method requires artisanal skill and time, and is the polar opposite of the modern "cold process method" that emphasizes efficiency. Complete saponification leaves no unreacted fats and oils, and the moisturizing effect of natural glycerin is maintained. A month of natural drying creates a dense soap.

He made many prototypes, tested them himself, and shared improvements with me, and we continued to make the product. As I continued to use the prototype, I noticed that although it initially improved the itchiness and other issues, I still had the problem of increased sebum secretion in the afternoon. It's a really trivial thing compared to before, but even that problem began to feel like a lie. Before I knew it, I had regained smooth hair that didn't feel sticky even in the afternoon, and stayed smooth all day.

I wanted to bring this joy to people with the same concerns. I wanted them to improve their scalp environment naturally, without the pain of going shampoo-free or relying on medication. And so, I finally completed it.

● How to use

~ Effective usage ~

1. Pre-wash
   Wet your hair and scalp thoroughly with lukewarm water.
   Wetting it thoroughly for a minute or two will help remove the dirt. 
2. Whisk
   Take the shampoo bar and press it directly onto your wet scalp, rubbing gently to create a lather. 
3. Massage Wash
   Spread the foam over your entire scalp and gently massage it in with your fingertips.
   The refreshing feeling of Japanese mint and the phytoncides of Japanese Sakhalin fir stimulate the scalp in a comfortable and healthy way. 
4. rinse
   Rinse thoroughly.
   It is important to rinse your shampoo bar thoroughly.

[Care after using the shampoo bar]

Due to the characteristics of soap shampoo, hair becomes alkaline after washing.

If you have been using shampoo containing synthetic surfactants for a long time, you may be concerned about dry hair.

In that case, we recommend using a citric acid rinse after washing your hair.

● Easy! How to make citric acid rinse

~ Basic ingredients ~

• Water: 500ml
• Citric acid: 1 tablespoon (approximately 15g)
• spray bottle 

~ Arrangement ~

If you are concerned about dryness or would like to enjoy your favorite scent, try mixing the basic ingredients with the following.

*It will not interfere with the scent of the shampoo bar. It blends well with any essential oils.

*If your scalp is sensitive, we recommend using a basic citric acid rinse.

• Glycerin: 1/2 to 1 teaspoon (2.5 ml to 5 ml)
• 2-3 drops of your favorite essential oil (lavender, rosemary, etc.) 

~ How to use ~

1. After washing your hair with the shampoo bar, rinse thoroughly.
2. Spray an appropriate amount of citric acid rinse onto wet hair.
   *Be careful as it will sting if it gets in your eyes.
3. Finally, rinse thoroughly with lukewarm water 

Why this shampoo bar works for seborrheic dermatitis

Why is the Hokkaido Botanical Shampoo Bar we developed so effective against seborrheic dermatitis? It's because it addresses the root cause of the disease .

First of all, it does not contain any synthetic surfactants. This means that it gently removes only excess dirt while protecting the scalp's essential sebum film. By maintaining the sebum film, the scalp no longer needs to secrete excess sebum, preventing the overgrowth of Malassezia fungus.

The Japanese mint in JM-23 has excellent antibacterial properties that naturally suppress the growth of Malassezia fungi. However, unlike fungicides, it does not completely eliminate resident bacteria, but works to restore balance. This is a major difference from medications. Medications may temporarily reduce bacteria, but they may also kill the good bacteria, ultimately worsening the scalp environment.

The blood circulation-promoting effect of Todomatsu essential oil improves the supply of nutrients to the scalp. By promoting healthy scalp cells, the scalp's natural healing ability is enhanced and inflammation is reduced. Furthermore, stress reduction, achieved through forest bathing, is also an important factor in improving seborrheic dermatitis. This is because stress is a major factor in increasing sebum secretion. While washing your hair, imagine yourself in a forest and take a deep breath.

The natural glycerin left behind by the kettle cooking method provides excellent moisturizing effects. Dryness can cause itching, and scratching can worsen the symptoms. Proper moisturizing can break this vicious cycle.

And most importantly, this shampoo bar helps restore the scalp's natural strength. Rather than suppressing symptoms like medicine, it normalizes the scalp environment, allowing symptoms to improve naturally. This leads to a fundamental solution.

During the first 2-3 weeks of use, there is an adjustment period during which the scalp environment, which has been disrupted by years of synthetic shampoo use, returns to normal. After this period, many people will notice a clear improvement.

Real voices from people who have actually made improvements

Since its release, we have received a steady stream of happy comments from people suffering from seborrheic dermatitis.

Mr. Chen (male), who lives in Taiwan , had been suffering from scalp itching and thinning hair for many years. "After about a week of using this shampoo bar, the itching clearly disappeared and I was able to sleep better. I never expected to see such an improvement without using medicine," he said with enthusiasm.

Ms. Wong (female) from Taiwan shared a happy report: "I was worried about switching from my usual shampoo, but it wasn't irritating at all and my hair has regained its strength. My daughter also had scalp problems, so I recommended this product to her, and she has also seen improvement." She is a devoted fan who regularly purchases our products and sends us her feedback.

It has only been on the market for half a month, but we have already received many encouraging comments. What these comments all have in common is that they "improved without relying on medication." This is not a temporary symptomatic treatment, but rather a fundamental improvement.

Choices that really save your scalp

To those of you who suffer from seborrheic dermatitis, I have something I want to say from my heart.

I don't intend to deny the use of medication. It may be necessary in the acute phase. However, I can say with certainty from my own experience that medication alone is not a fundamental solution.

The important thing is to understand the cause of seborrheic dermatitis and to reassess your lifestyle. Reassess your daily shampoo, get into the habit of soaking in a bath, or if you don't have a bath, exercise, sweat, raise your body temperature, and boost your immunity. Just doing this can make a big difference.

Incidentally, when your body temperature rises and you start sweating, the itching can get worse. This is a normal reaction that occurs when your body tries to expel foreign substances from the skin. Therefore, suppressing the itching with medications such as steroids can actually weaken your immune system, preventing your body from responding normally.

Hokkaido Botanical Shampoo Bar is more than just a soapy shampoo. I developed this product as a product for those who suffer from seborrheic dermatitis, myself included . This shampoo bar combines miraculous ingredients nurtured by Hokkaido's natural beauty with traditional Japanese techniques, and truly aims to heal with the power of nature.

Don't expect dramatic results right away. It takes time for your scalp to normalize. However, after a 2-3 week adjustment period, you should notice a difference. After a few months, you'll have a healthy scalp that doesn't require medication.

Eventually, you will be able to reduce the frequency of shampooing. In summer, once every 2-3 days will be sufficient, and in winter, once a week will be sufficient. You will be able to get by comfortably with just hot water on more days. This is the true meaning of scalp health.

After a painful experience in Taiwan, I finally found the answer: seborrheic dermatitis can definitely be improved. Don't give up.

Take the first step to a truly healthy scalp that's free from chemicals. For beautiful hair 10 or even 20 years from now. And most importantly, for relief from itching and dandruff right now.

I sincerely hope that your decision will be the first step in changing your life.

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.

This is also recommended for washing your face!

SORRY KOUBOU Honey Soap, 60g, Handmade in a Kamikake (Hokkaido), Sensitive Skin

Contains honey and calendula from Hokkaido. Carefully handcrafted using a kettle-fired method to remove impurities. It has passed botulinum testing, so it can be used safely not only on the face but also on the whole body and in shampoo bars. Enjoy the gentle fragrance of natural herbs. Click here for more details.

Gentle on the skin, chamomile soap, 60g, Hokkaido, pesticide-free, kettle-fired, handmade soap

This product is made with generous amounts of organically grown, pesticide-free chamomile, carefully cultivated in Shimokawa, Hokkaido. Each product is handcrafted by artisans using the traditional "kettle cooking method," which removes impurities and minimizes skin irritation. With a gentle herbal scent, it's recommended not only for washing your face, but also for use on your whole body and as a shampoo bar.