Let’s Get Buried In Fermented Rice Bran !!

What do you mean “Let’s get buried in fermented rice bran?!” I don’t get it! This isn’t a hot spring! I’m pretty sure there are a lot of people who had these thoughts, but just as it’s written, getting buried in this fermented rice bran is one method of bathing. The rice bran is kind of like Suna-yu’s sand. Recently, this method of bathing, called “Kouso-Buro,” has slowly been gaining popularity in Japan. Today, we’re going to introduce Kaju, who offers this “Kouso-Buro.” Because I’ve actually experienced this myself, I’m going to share about it today to satisfy that lingering question – “What the heck is Kouso-Buro?!”

What in the world is “Kouso-Buro” (Enzyme Bath) ??

Kouso-Buro is a hot bath method which utilizes heat produced when rice ran of sawdust ferment. At Kaju, they make use of the hot springs’ heat to promote the growth of enzymes through the function of microbes, and the body is buried under the warmed rice bran.

You can’t see it with your eyes, but the functioning microbes are pretty incredible! There are probably people who are thinking, “Okay, but I’d rather not have things like microbes and fermentation sticking to me!” But these enzymes are actually something very familiar to us. Japan’s sake, miso, and soy sauce, in particular, are fermented products made through the power of microbes. Cheese and beer, too! Moreover, there are pleasant effects that stem from enzymes. We’ll see how we can experience it and what kind of effects it has next.

How to do it, and What is it good for ?

I think it’s easier for people who have experience with sand baths and saunas to imagine, but in Kouso-Buro, you sweat a lot over time. For a detoxing effect and to keep you from feeling sick afterwards, it’s recommended you drink enough water beforehand.



After drinking enough water, you’ll take a light shower. During this time, be careful not to wet your hair! When you shower, you can change into the disposal underwear given to you at the reception desk. Also, because each dressing room is equipped with its own shower, your privacy is well-protected! The underwear’s appearance is a little embarrassing but the staff are women so other women can rest easy, and you’ll be buried in sand soon anyway, so it’s fine!!!

Once you’ve put your valuables in a locker (key provided) and all your things are in order, it’s off to the bathroom! The moment you enter the bathroom, you’ll be hit with a unique smell. It’s not exactly stinky, but it is very distinct, so there may be people who aren’t so fond of it. If you aren’t feeling so great, communicate that as soon as possible!

The strange experience before you might have your heart pounding, but the moment you put one foot in the rice bran, you’ll feel that nervousness float away. It’s so nice and warm – that feeling of happiness like ‘Ah… what is this?~’ takes over. I loved it instantly. Once you’ve changed your clothes, the staff good-naturedly digs up the hole where you are to be buried. To keep the burden on the body to a minimum, the body is supposed to be raised slightly when buried.

Once you’re in the hole, the staff will kindly bury your body using a shovel.

You might think that getting buried is painful, but it really isn’t because the rice bran is so light. The soft sawdust wraps you up just right in a feeling of warmth and safety. It might even be better than a high quality bed! If you request it, they’ll bury you entirely, excluding your nose and mouth. Like this:

It’s that kind of feeling. Gradually warming up the head, especially the eyes, feels really good – contrary to what everyone might think – so I think you should try it if you get the chance. Your eyes and head will be wrapped in a towel, so don’t worry about having your head filled with rice bran! But apparently, the enzymes are good for your hair so there is an option to leave it out. Being buried generally lasts for 15 minutes. During the colder seasons or instances where the person wants to warm up a little more, you can stay for 20 minutes while keeping an eye on your state. Conversely, if you aren’t feeling well, you can let the staff know at any time! When you want to get out, just say, “Detaidesu” and they’ll get you out!

Because “Kouso-Buro” warms you up gradually over a long period of time, you’re warmed up from your core. That result surpasses that of getting into a hot bath. Apparently, there are lots of people prone to hypothermia nowadays. Unfortunately, hypothermia causes one’s metabolism to decrease, making it easy to gain weight, and also causes aging and the declining of one’s immune system. In women’s case, it worsens menstrual pain and also makes it difficult to conceive. For that reason, slowly warming up the body in this way and raising one’s basal body temperature is very important.


After being tried for a while, the enzymes might become lukewarm. Should that happen, let the staff know or try moving your hands and toes to gather new enzymes to your person. If you do that, it’ll become warm again. By the way, in the span of you being buried, you might feel that some places or hot or cold. Those feelings are a bad sign! Not only is Kouso-Buro good for your body, but also gives you a complete health check-up! It’s awesome!

When you come up from Kouso-Buro, you’ll have to lightly shake off the rice bran outside the tub and then take a shower. You’ve got to be careful because the rice bran grains are smaller than you think and will make your towel and clothes brown if you don’t wash it off properly! Additionally, you sweat way more than you think, so hydrate properly as well! If you ask the staff, they’ll also lend you a drier.

Now then, I’ve shared my experience with Kouso-Buro and how great it feels, but a little after I finished, I really felt Kouso-Buro’s amazingness even more.

First off, my body felt so nice and warm! Afterwards, my skin was silky smooth!! It’s probably because the vitamins and minerals from the rice bran entered through my skin, raising my metabolism and removing the waste from my skin!

Other options at Kaju

At Kaju, for the sake of health and beauty, they’ve put together a menu with options, such as steam using traditional Chinese medicines, inter-cerebral detox, and massages alongside Kouso-Buro. It might be good taking the full course and completely resetting the body.

Kaju is about a 20 minute walk from Beppu Station. It might be good for those who are anxious about the way to get there or language barriers to take the travel assessment and rely on a guide. The travel assessment offers recommended hot springs and suggestions on how you could spend your time in Beppu. Consulting this, let’s get to planning out your trip to Beppu!

Basic Info

OPEN: 10:00 – 20:00
FEE: 3,500 YEN
TATTOO: Allowed

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