Based on 797 reviews
Love It

Love it!! This product has changed my gut health (for the better) forever. I thank God for them and their product. Thanks so much.

good taste, seems to work

Friend of mine had recommended this. I've been taking 1-2 servings a day, in the mornings, and do feel less bloated the rest of the day. Looking to continue a subscription for a few months and try a 1- or 3-day cleanse.

Great Product

I love taking this product and feel more better taking it than before.

Trial Pack

Packaged really well and arrived on expected delivery date. Helped really well with bloating. Wish they provided more bottles in box. Would say they should make a travel box when going on trips.

R's KOSO Lower Sugar - Japanese Postbiotic Drink (280ml / 9.5oz)

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

Amazing Product

I bought my first bottle and lost six pounds within two days of drinking only R’s Koso. I was hoping to go the full three days and was not successful, but I am going to try it again. I am very happy, though, with the results for the two days I was on the cleanse. I drank the rest of the bottle for breakfast following my two day cleanse.

I would say I’m in shape and very active, so my body weight is generally at a steady place. But after the holidays brought on some weight, I was pleasantly surprised when I did this to detox and saw such drastic changes happen within two days! I would highly recommend this product!

Well. I drank this.

Good favorite. Feel little healthy. Keep

Great Probiotic Drink

Enjoy the flavor and easy to take each day. Ordered another.

Excellent product I love it Excellent health benefits in short time

R's KOSO Lower Sugar - Japanese Postbiotic Drink (280ml / 9.5oz)

Great Cleanse

The koso kept my blood sugar levels stable so I never felt “hangry” - so a 3 day cleanse was easily doable

My review

Incorporating this drink every morning as breakfast and every night to help digest my dinner. So far, I’ve noticed that there’s a gap between days I can have a bowel movement. Since starting this drink, one week I would feel constipated for at least 2 days and other times I’ll be constipated for one day. One positive thing about this is that my acid reflux hasn’t flared since taking it. It really does help with my digestive system feeling comfortable. Wish it’ll help me go regularly though. Perhaps I need to continue a little longer or try the 3-day cleanse to reboot my digestive tract. We shall see

Absolutely love it!

I did the 3 day fast 2 years ago and have been doing the morning break-fast with a koso since. Makes you feel full, satisfied but also gives me energy and vitamin supplements i need.

Delicious & Satisfying

Not only is Koso tasty, it’s fulfilling, in a light dessert-like way. All the health benefits, offered in a drinkable beverage… I look forward to my Koso drink in the evenings.

The best Japanese drink!!!

The best product. I’m going to buy more! It helps me a lot. I’m your loyal customer!

Amazing! RS Koso really works! And it’s healthy for you!

In just one week, I shed 8 pounds, slimmed down my waist, and achieved a radiant complexion! Opting for the low-sugar option, I never felt hungry during the cleanse. This is the first time in a while that I've successfully completed a cleanse. My independent research also shows that this is healthy for you.

Outstanding Product

I have been taking R’s KOSO now for about three months consecutively. I feel less cravings, more satisfied, and very excited to drink this stuff all day long. I love it mixed with cranberry club soda!

It has been working great for me!

I’ve been drinking Koso everyday for almost three months, tried the one-day cleanse for about twice but decided to just do the daily breakfast cleanse out of my hangry nature; I’ve tried both the classic and the lower sugar Koso and I like the taste of both. The classic Koso tasts like honey or syrup, and I like to add two tablespoons to a zero-sugar added cranberry juice. The lower sugar Koso still has a natural sweetness from the fruits and vegetables and I either drink it with water or with any juice I like.

I don’t want to gross anyone out but I have to say Koso has made everything really smooth. I’ve noticed that my metabolism had slowed down significantly over several years due to high stress at work and less time for exercise, but since I started my Koso routine, I’ve felt that things are starting to get back to normal. I made a couple of friends try Koso with me and they both felt the results as well.

Definitely recommend both the classic and the lower sugar Koso to everyone!

Tastes as good as the original

Although the quantity of concentrate required to make a serving is less, the taste is nearly the same, just less sweet. I recommend this product!

Low sugar

Great idea I love your product
The only problem living in France no way to subscribe and get a lower price
Would be great if I could subscribe

Very convenient for travel

I like RS Koso and these are very convenient for travel, especially if you don’t have a fridge wherever you are going or are going only a few days. Just too expensive compared to the bottle and they won’t sell you more than 1 box of these mini bottles

It's a great drink but a bit pricey even with the monthly subscription discount. Didn't really notice any difference. I've been doing the 4x/week for 3+ months

Great probiotics drink

It’s very good taste to mix with sparkling water . it helps me improve my digestion . Only thing is that I did not do cleansing as suggested.

R's KOSO Lower Sugar - Japanese Postbiotic Drink (280ml / 9.5oz)

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