Based on 168 reviews

Excellent product. I hope they can lower their prices to make it more accessible to more people.

New Trial Pack - Japanese Prebiotic Drink (30ml/1oz × 5 bottles) - R's KOSO -

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

R's KOSO - Japanese Prebiotic Drink (474ml / 16oz)×2 bottles

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

Koso review

I ordered for my friend who has had stomach issues for many years, she thinks it has really helped her right away, but unfortunately for someone on a fixed budget it is really not affordable. Fantastic product though ! !

Love it as a natural source of probiotics.

Great quality, great taste

I used to drink Koso when I was in Japan and experienced great benefits so I was really happy to find your company that offer great quality koso in the US! I plan to continue my subscription indefinitely. Thank you :)

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

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

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

Less Bloating

Really like this product. Had much less bloating and feel healthier

No comment yet. I have just started. It tastes good though.

The taste wasn't too bad

I can not say whether or not I saw or felt a difference within the 5 days I took it. BUT! when I drank it I wasn't hungry, and thinking by the end of the 5 days (I eat pretty well this was as a supplement) I was sleeping and a bit less lethargic. It says it tastes like a plum drink, this is a partial truth. it does initially... but then the syrup gets EXTREMELY heavy-handed with the vegetal aftertaste. It is like syrupy sweet salad water runoff with preserved plum. very "organic" tasting. you KNOW it is made from plants. I honestly liked it enough that I plan on buying a full-sized bottle.

Pleasant surprise

I was pleasantly surprise by the taste. It’s sweet and it was like drinking honey water. I enjoyed my trial pack and will be ordering more.


This completely flatens the bloating. BEST DRINK EVER.

While the benefits of taking this product is substantial I I did not loose any weight at the of the 3 das cleans; I felt lighter but no weight lost which my only reason for buying it.

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

Glad I found it

I think this is the perfect breakfast for me since I'm never hungry when I wake up, I also use intermittent fasting with this and have noticed no more stomach issues like bloating, indigestion and reflux. Also lost some weight! would 100% recommend

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

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

KOSO of the century!

R’s KOSO helped me bounce back from caffeine dependency, filled me up with natural energy and motivation to get my health in check! There are many options on how to do a cleanse with R’s KOSO, which was helpfully written in the pamphlet sent with the package. I had switched over to a vegan diet a week before starting the 3-day cleanse and have been experiencing incredible results. Waking up naturally at 7am without an alarm (!) has changed the game for me! Not to mention the boost of clarity, energy throughout the day as well as increased metabolism.

Thank you for creating an amazing product!

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