Daily wellness
Anyone building a healthy diet
Support a healthy diet with adequate daily fiber.
Gut Support · Microbiome DiversityMango15 servings
Microbiome Fiber for Gut Support
A daily prebiotic fiber formula with clinically studied Actazin® green kiwifruit and diverse prebiotic fibers to nourish your gut.
Seven prebiotic fibers at clinically studied doses
Combined into one convenient two-scoop serving.
Actazin® green kiwifruit · Resistant tapioca fiber · Acacia gum · FOS · Guar gum · XOS · IMO
- Supports digestive wellness and healthy regularity*
- Nourishes beneficial gut bacteria with multiple prebiotic fiber sources*
- Helps promote the production of beneficial short chain fatty acids*
- USDA Organic, Vegan, Non-GMO, gluten free, no artificial ingredients
- Two scoops daily. Mix into water, smoothies, or yogurt.
In every two-scoop serving
- 600 mg
- Actazin® Green Kiwifruit
- 3 g
- Resistant Tapioca Fiber
- 2 g
- Acacia Gum
- 2 g
- FOS (Fructooligosaccharides)
- 2 g
- Guar Gum (PHGG)
- 1.5 g
- XOS · IMO
Seven prebiotic fibers at clinically studied doses. Every amount printed on the label.
Description
Just as a healthy ecosystem depends on biodiversity, a healthy microbiome benefits from a diverse supply of fibers that nourish different populations of beneficial bacteria. A single fiber may nourish only a limited range of microbes.
KOS Microbiome Fiber is a daily prebiotic blend that pairs patented Actazin® green kiwifruit, rich in bioactive compounds, with six complementary fiber sources: organic resistant tapioca fiber, acacia gum, FOS, guar gum, XOS, and IMO. Together, this diverse blend helps nourish a wider range of beneficial bacteria supporting a more diverse, resilient, and balanced gut ecosystem.*
- Seven soluble, fermentable prebiotic fibers to support microbiome diversity
- Multi-fiber blend, not just a single fiber source
- Third-party tested and made in a GMP-certified facility
What to expect
Fiber begins working with your gut from the first serving, but noticeable changes may take time.
Days 1-7: Your gut begins adapting. Changes in regularity or temporary gas and bloating may occur.
Weeks 2-4: Prebiotic fibers continue nourishing beneficial bacteria. You may notice steadier regularity and digestive comfort.*
Week 4+: Daily use helps support digestive wellness and microbiome diversity over time.*
Fiber needs water to expand and move smoothly. Start with one scoop daily, and work up to two scoops as tolerated.
Why you'll love it
- Seven soluble, prebiotic fibers at clinically studied doses
- Actazin®, patented ingredient sourced from premium New Zealand kiwifruit
- 8 grams of prebiotic fiber per serving
- Delicious mango flavor with no artificial ingredients or harsh laxatives
- Works alongside inulin to increase prebiotic fiber intake and diversity
How to use
Mix two scoops into 8-12 oz of cold water, juice, or your favorite smoothie. Stir or shake until dissolved.
Take it daily. If you're new to prebiotic fibers, start with one scoop and gradually increase to two over the first week to give your gut time to adjust.
Is it safe?
Prebiotic fibers are generally well-tolerated by most healthy adults when used as directed. Temporary gas, bloating, or changes in bowel habits may occur, especially when first increasing fiber intake.
Consult your healthcare provider before use if you are pregnant, nursing, taking medication, or managing a health condition, especially IBS or SIBO.
Guarantee & shipping
Try Microbiome Fiber for 15 days. If you don't feel a difference, email hello@kos.com for a full refund.
Orders usually arrive in 3 - 5 days. Free shipping over $75.
*These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.
Nourish your gut. Support your microbiome.
Seven fermentable prebiotic fibers, working together. Not just a single fiber source.
Digestive Wellness
Supports digestive comfort and healthy regularity so you can feel your best every day.*
Microbiome Diversity
Nourishes beneficial gut bacteria with multiple prebiotic fiber sources for a more diverse and resilient gut ecosystem.*
Gut Barrier Support
Supports the production of short chain fatty acids that help maintain the health of the intestinal environment and gut lining.*
Clean & Thoughtful
USDA Organic, Vegan, Non-GMO, and Gluten Free with no artificial ingredients.
Myths vs Facts
What you need to know about fiber
-
Myth
Fiber is just for regularity.
TruthFiber does more than support regularity. It nourishes beneficial gut bacteria and supports short-chain fatty acid production, microbiome diversity, and gut barrier health.*
-
Myth
One fiber source is enough.
TruthOne fiber source feeds only certain bacteria, while multiple fiber sources nourish a wider range, supporting a more diverse, resilient, and balanced gut ecosystem.*
-
Myth
Only people with digestive issues need it.
TruthAdequate fiber intake is important for most adults. Microbiome Fiber is broadly relevant, not only for people with digestive concerns. Adequate fiber intake is also important for people concerned about cholesterol and triglycerides, alongside other dietary and lifestyle factors.
-
Myth
Fiber makes you bloated.
TruthToo much fiber too quickly may cause temporary gas or bloating. Start with one scoop and increase to two as tolerated.
-
Myth
I take inulin, so I don't need another fiber.
TruthMicrobiome Fiber works alongside inulin to increase prebiotic fiber intake and variety.
-
Myth
Menopause and gut health aren't connected.
TruthHormonal shifts during perimenopause and menopause impact the gut and gut-brain axis, making daily fiber support especially valuable during these transitions.*
Every ingredient. Every dose. On the label.
No proprietary blend. Supports gut health from the inside out.
600 mg
Actazin® Green Kiwifruit
A patented New Zealand green kiwifruit prebiotic shown in clinical studies to support digestive comfort, healthy regularity, and overall gut wellness.*
3 g
Resistant Tapioca Fiber
A gentle, soluble prebiotic fiber that supports healthy regularity and nourishes beneficial gut bacteria.*
2 g
Acacia Gum
A soluble prebiotic fiber that helps support gut microbiome diversity and overall digestive wellness.*
2 g
FOS (Fructooligosaccharides)
A prebiotic fiber that selectively feeds beneficial bacteria and helps promote a healthy gut environment.*
2 g
Guar Gum (PHGG)
A soluble fiber that helps support digestive health and contributes to a feeling of regularity and comfort.*
1 g
XOS (Xylooligosaccharides)
A prebiotic fiber that helps nourish beneficial bacteria and supports microbiome diversity.*
500 mg
IMO (Isomalto-oligosaccharides)
A gently fermented prebiotic fiber that supports digestive comfort and healthy intestinal function.*
Each ingredient was thoughtfully selected for quality, integrity, and scientific support.
How it works
How prebiotic fiber supports your gut
- 01
Prebiotic fibers
Nourish beneficial bacteria already in your gut.
- 02
Good bacteria ferment
The microbiome breaks down these fibers.
- 03
SCFAs produced
Fermentation produces short chain fatty acids.
- 04
Gut environment supported
SCFAs help maintain a healthy gut lining and environment.*
- 05
Better daily wellness
The result: better gut health, regularity, comfort, and microbiome diversity.*
Meaningful microbiome support, formulated to fit easily into your daily routine.
Microbiome Fiber vs a typical fiber supplement
KOS Microbiome Fiber
Typical Fiber Supplement
Supports digestive wellness and regularity*
✓
✓
Seven prebiotic fibers at clinically studied doses
✓
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Features patented Actazin® green kiwifruit
✓
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Nourishes a broad range of beneficial gut bacteria*
✓
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Pleasant texture & easy to incorporate into daily routine
✓
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USDA Organic with no artificial ingredients
✓
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A prebiotic-first philosophy
Microbiome Fiber was intentionally formulated as a comprehensive prebiotic fiber supplement. Digestive enzymes help break down the food you eat, while probiotics introduce live microorganisms into the digestive tract.
Prebiotics work differently: they nourish the beneficial bacteria already living in your gut. By bringing together a diverse blend of clinically supported, complementary prebiotic fibers in one convenient daily formula, Microbiome Fiber helps nourish the healthy microbial community already there and support long-term digestive wellness, without relying on digestive enzymes or live probiotic cultures.*
Nourish what's already there.
Who is it for
Daily support across wellness goals, life stages, and routines.
Perimenopause & menopause
During hormonal shifts
Support gut health through hormonal transitions, with broader implications for the gut-brain axis and overall well-being.*
Cardiometabolic health
Cholesterol & triglyceride support
Support cardiometabolic wellness with adequate fiber intake alongside other dietary and lifestyle factors.*
Alongside inulin
Anyone seeking greater prebiotic diversity
Increase overall prebiotic fiber intake and diversity by pairing Microbiome Fiber with inulin.
What customers say
4.8
Regularity feels effortless now
About three weeks in and things just work. Mixes clean in cold water, no grit, no chalkiness.
Sarah L.Verified buyer
Mango flavor is genuinely good
I've tried fiber powders that were undrinkable. This one goes down easy. No bloat once I ramped up over a week.
Danielle R.Verified buyer
Doing my gut a favor
Bought it after reading about microbiome diversity. Took a few weeks but I feel noticeably better after meals.
James P.Verified buyer
Real customer reviews land here, gathered by email about a month after purchase. Low scores shown too. Free-sample reviews disclosed.
Frequently asked questions
Still unsure? Email hello@kos.com and a human will answer.
How do I take it?
Mix two scoops into 8-12 oz of water, juice, or a smoothie. Take it daily. If you're new to fiber, start with one scoop and increase gradually as tolerated.
What's the difference between prebiotics and probiotics?
Probiotics are live beneficial microorganisms. Prebiotics are fermentable fibers that feed the good microorganisms already in your gut. They perform different roles and complement each other.
When will I feel something?
Individual experiences vary. You may notice changes in regularity within the first week, with steadier digestive comfort developing over 2-4 weeks. Consistent daily use supports microbiome diversity over time.*
Why seven fibers instead of one?
Different beneficial bacteria thrive on different fibers, so this seven-fiber blend nourishes a broader range of microbes than a single-source fiber. This helps support microbiome diversity and gut resilience.*
Can I take it with inulin or other fiber supplements?
Yes, it can be used with inulin to increase overall fiber intake and diversity. When combining it with other fibers follow each product's directions.
Will it make me bloated?
Some people experience temporary gas or bloating while the microbiome adjusts to more fiber. Start with one scoop and gradually increase to two as tolerated.
Is it safe for perimenopause or menopause?
Yes. It can be especially valuable during perimenopause and menopause because gut health can support the gut-brain axis and overall well-being.* Consult your healthcare provider if you have specific concerns.
What does it taste like?
Lightly sweet mango flavor with no artificial ingredients. Mix it into cold water, smoothies or yogurt for a simple, delicious way to make gut health part of your daily routine.
Can I take it with other KOS products?
Yes. It stacks well with our protein powders and other daily formulas.
Who is this for?
Fiber is an important part of a healthy diet for most people, making Microbiome Fiber broadly relevant rather than limited to one demographic. It's valuable for adults focused on digestive comfort, cardiometabolic wellness, or well-being during perimenopause and menopause.*
Nourish your gut. Support your microbiome. Feel your best.*
The KOS Promise- Plant Powered USDA Organic, Vegan, Non-GMO.
- Clean Ingredients No artificial colors, flavors, or sweeteners.
- Third Party Tested Checked by an independent lab, not by us.
- Quality You Can Trust Made in a GMP-certified facility.
- Made With Care Full doses printed on the label. Nothing hidden.
Add to cart$29.99
30 two-scoop servings per tubor subscribe & save 20%
- 15 day money back guarantee
- Free shipping over $75
- Usually arrives in 3 - 5 days
*These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.
Want the science behind the formula? Read why fiber diversity matters for your gut microbiome.
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