R's KOSO - Japanese Postbiotic Drink (474ml / 16oz)

Product image 1R's KOSO - Japanese Postbiotic Drink (474ml / 16oz)
Product image 2R's KOSO - Japanese Postbiotic Drink (474ml / 16oz)
Product image 3R's KOSO - Japanese Prebiotic Drink (474ml / 16oz) - R's KOSO
Product image 4R's KOSO - Japanese Postbiotic Drink (474ml / 16oz)
Product image 5R's KOSO - Japanese Postbiotic Drink (474ml / 16oz)
Product image 6R's KOSO - Japanese Postbiotic Drink (474ml / 16oz)

Regular price $99.00


- Fermented Superfood, 100+ Vegetables, Fruits, Probiotics, Prebiotics & Postbiotics Cleanse -

“Koso” means enzyme or ferment in Japanese. Koso drink is a century-old traditional fermented drink made from vegetables, fruits, and plants. It's an essential part of the Japanese style of juice cleanses or intermittent fasting. Koso Cleanse is a century-old traditional Japanese juice cleansing method that has proven to keep your gut healthy.

R’s KOSO is the only superfood supplement on the market that provides balanced nutrition, combining probiotics, prebiotics and, postbiotics, which have proven to improve gut health and boost immunity. It's made from over 100 vegetables, fruits, and plants, including seaweeds and mushrooms, and undergoes about 1-year fermentation process. You can enjoy it as a daily supplement but also cleansing and fasting with R's KOSO is a great way to reset your digestive system, and restoring microbiome health.

Good to know : NON-GMO, Dairy-free, VEGAN-friendly, Japan Made, Gluten-Free, 1-year fermentation, Contains Probiotics & Prebiotics. 70 years' experience to make Koso.

* The taste like Sweet Japanese plum juice. We recommend mix with sparkling water. It's going to be Plum flavor Prebiotic Soda.


Enhance gut health - our century-old traditional Japanese fermentation process provides a natural, plant-based, probiotic to support digestive health, skin radiance and, immune system.

Feeds your microbiome - rich in prebiotics and dietary fiber to feed the beneficial bacteria that reside in your gut and promote a healthy gut.

Better digestion - rich in probiotics and prebiotics to help you absorb more nutrients from the ingredients in the formula as well as the other foods you eat.

Healthy weight - Studies show taking prebiotic fiber caused positive changes in the gut microbiome, including increased levels of beneficial bacteria that are associated with a decrease in fat mass.

Antioxidant-rich - contain abundant functional ingredients, i.e., polyphenols, vitamin A, E, C. It gives your body a powerful shot of helping you neutralize toxins and promote healthy, clear skin, anti-aging.

Boost Immune system - our fermented superfood supplement made from 100+ vegetables and fruits, provides balanced nutrition, combining probiotics and prebiotics. The gut actually has about 70 percent of the body's immune cells. Taking balanced food is one of the big ideas to keep a healthy gut and boost immunity.


Serving size:Daily Enjoyment Use: Mix 15 ml /0.5 oz of R’s KOSO with 1/4 cup of sparkling water (or filtered water). 1-2 times per day before breakfast or/and dinner.
Cleanse Use: Mix 30 ml /1 oz of R’s KOSO with 1/2 cup of sparkling water (or filtered water). 1-5 times per day.

Storage:Refrigerate after opening and use within 4 weeks.

Methods:Try Koso Cleanse. 1 bottles is good for the following.

Methods Good For Suggested Use Recommended Duration

Breakfast Cleanse (every day)

2 weeks

1 time/day

12 weeks

Breakfast Cleanse (4 Days/w)

4 weeks

1 time/day

12 weeks

1-Day Cleanse

3-4 weeks

3-5 times/day

12 weeks

3-Day Cleanse

1 program

3-5 times/day

Every 2 months

Daily Enjoyment

2-4 weeks

1-2 times/day

Every day (at least 12 weeks)


- 100+ INGREDIENTS - Vegetables, Fruits, Seaweeds, Mushrooms -

Leafy vegetables mix (cabbage, napa cabbage, lettuce, asparagus, broccoli, canola flower, celery, cauliflower, japanese mustard spinach, spinach, bok choy, taro stem, crown daisy, chisha lettuce, parsley, sprouts, perilla), Fruit vegetables mix (cucumber, wax gourd, tomato, eggplant, squash, bitter gourd, watermelon, corn, okra, bell pepper), Root vegetables mix (daikon, turnip, ginger, udo, yamato yam, nagaimo, potato, yam, japanese yam, sweet potato, carrot, lotus root, taro, burdock, lily bulb), Fruits mix (apple, quince, loquat, japanese plum, strawberry, chocolate vine, kumquat, apricot, sudachi, fig, mandarin orange, iyokan, kiwifruit, persimmon, peach, cherry, melon, grape, plum, pear), Brown sugar, Crude sugar, Malt sugar, Galacto-Oligosaccharide, Beet sugar, Starch, Japanese plum extract, Beans mix (kidney bean, snow peas, fava beans, soybeans, black soybeans, red beans), Mushrooms mix (shiitake, shimeji, eryngii, wood ear, maitake, crimini, enokitake), Cereals mix (black rice, brown rice, red rice, sticky millet, barnyard millet), Seaweeds mix (kelp, wakame, sea lettuce, hijiki, nori, mozuku, tengusa), Herbs mix (plantago, dandelion, kumazasa, clover, aucuba, chickweed, saxifraga stolonifera, agrimonia pilosa, achyranthes bidentate, horsetail, japanese knotweed, water dropwort, mugwort, persimmon leaf, pine needles, cedar leaf, hiba, goji leaf, mulberry leaf), Koji, Yeast, Lactic acid bacteria. contain: Soy
*All ingredients are fermented together. It may vary in color, texture, and flavor due to seasonal and crop variances

- 1-YEAR FERMENTATION - Prebiotics and Probiotics -

A century-old traditional drink, Koso has good bacteria which are Lactobacillus brevis, Lactobacillus plantarum, Lactobacillus casei, Lactococcus lactis. And galactooligosaccharide and dietary fiber are included as prebiotics. Dandelion Greens, Asparagus, apples, Burdock, Barley, Seaweeds act as prebiotics ingredients.


What does R's KOSO taste like?
R's KOSO is a Japanese plum flavored drink.

Is R's KOSO vegan?
Yes. R's KOSO does not contain animal-derived ingredients and the drink is plant-based.

How long has it been fermented?
R’s KOSO is fermented for about 1 year.

What’s the best way to take R's KOSO?
We recommend mixing 2 tablespoons of R's KOSO with ½ cup of sparkling water (or filtered water) for cleansing. It's also good to take with yogurt for daily enjoyment.

Is there an optimal time of day to take R's KOSO?
No, it can be taken at any time of the day that suits you. Especially we recommend you drink after you eat/drink too much. It is helpful to digest. Actually many Japanese women take it after dinner or replace the meal.

How does it compare to the Kombucha and other drinks?
R's KOSO is the only 100% plant-based supplement which has probiotics, prebiotics, postbiotics, acetic acid, Phenolics, vegetable, and fruits nutrients, Vitamins (A, B1, B2, B6, C, D, E, and K), Mineral (calcium, phosphorus, potassium, sodium, chloride, magnesium, iodine, iron, zinc, copper, manganese, iodine), 17+ Amino Acids, Short-chain fatty acid.

How different between Juice cleanse and Koso Cleanse?
R’s Koso’s Main feature is the benefit of Gut health. Compared to Juice cleanse, Koso Cleanse has probiotics and prebiotics that have positive impacts on your gut. Some research reveals that the gut is connected to the brain and skin.

How can we control our blood sugar?
If you concern about blood sugar, we recommend consuming Koso a little less or drinking it for 1-2 hours.

Is R's KOSO safe to use when pregnant and when breastfeeding?
Yes, it's all natural plant-based food so you can take it.

Can I take it with other supplements?
Yes, R's KOSO can be taken with every other supplement because it's food.

Does it contain preservatives?
No, it is not contained it. The fermentation process made its shelf life longer.

Customer Reviews

Based on 511 reviews
Lokesh R.
Koso review but pricey

It has worked wonders with my system and feel good just going through the full bottle consuming 30ml with water as a substitute for breakfast replacement. It is very pricey, it would be great to buy this around $35.

Wei Z.


Works on me!

Helped me with my cravings!
I don’t crave sugars anymore.
Less bloating too.
Finished my 1st bottle, ordered 2 more and already subscribed.
It’s my breakfast and dinner routine.
Love it!

Trina N.
Not working for me

I did the drink to replace my morning meal. I didn’t feel any difference or has any experience like people’ in the the advertisement .
I feel like mine 100$ Is wasted!
Also ,it doesn’t taste like plum juice , it tastes more like the red Cabbage juice.

Noriko E.

I love its complex, sweet taste! I add it to my smoothie every morning.

Nicholas G.
Helpful for stomach issue

I had a terrible case of leaky gut, and I spent months vomiting for hours every morning before I could get out the door. I’d have to wake up 5 hours before I left my house just to make sure I wasn’t going to throw up all over myself once I got in the car. I was also 436 lbs and totally miserable. I’m not gonna say that I got this drink and lost 140 lbs because that didn’t happen. I dieted and got down to 320 lbs before I got Koso, then I decided to do an extended fast with the aid of Koso, at this point my stomach was quite a bit better, but I was still throwing up most mornings and nauseous as hell every morning. I started my cleanse and every morning I would wake up sick, swallow the Koso, lay down and within 30 minutes if feel a bit more stable and was able to start moving around. I’d have another before leaving for work, and 1 or 2 more during my work day. It helped keep my stomach balanced and kept the nausea away. Day 2 was hard because of all the ghrelin, but after my 2nd Koso drink of the day I felt totally fine and hunger was gone. 3rd through 5th day we’re very very easy, I added water with fresh lemon throughout the whole day. I will definitely be doing another long term fast with Koso as an aid when I get my next bottle. I’m also getting my mom interested and I think it’d help her a lot too. The taste is great, I love it with the sparkling water. I could see some people having the smell turn them off, but it reminded me of branston which I love. It smells like fermented stuff, so if you like fermented foods you’ll be fine, if you’re not used to them then you might want to use extra water. This is an excellent product that I believe really helped me in my journey. I’m down to 295 now, and my stomach is much better than before the cleanse.

The results are amazing!

I started with the three day cleanse, with the results being amazing. My body felt more energized, my bloating subsided, and lost 2-3 pounds initially. The first day was exciting, I felt hungry the second day, but by the third day was fine. After the cleanse, I decided to do maintenance once daily to keep the bloating down. And it did just that! Since usage, I’ve lost 8 pounds of steady loss without being hungry. What has changed is I don’t crave sugars, or any junk food, I sleep much better, I feel energized, I’m very regulated, I don't have the bloating and I feel great. I did a review when I first started using it, and my only contribution was the taste. After two months, the results speak for the product. I plan to use this as daily maintenance, and once monthly do a one day cleanse.

Crystal J.
Enjoying my Koso so far

The taste is wonderful and has been a great addition to my daily routine, since my IBS requires I get enough probiotics on a daily basis. I have definitely been experiencing a decrease in my IBS symptoms, like the bloating and stomach upset. I’ve recently started taking the Koso in the evening as well, so really looking forward to how that goes. I highly recommend if you’re at all on the fence. It’s totally worth the price for the health benefits and overall wellness

Colombe K.
Great product

Really love it

Close (esc)


Use this popup to embed a mailing list sign up form. Alternatively use it as a simple call to action with a link to a product or a page.

Age verification

By clicking enter you are verifying that you are old enough to consume alcohol.


Main menu

Shopping Cart

Your cart is currently empty.
Shop now
Liquid error: Could not find asset snippets/elevar-body-end.liquid HTMLResult Skip Results Iframe EDIT ON