Phase Fiber™ Prebiotic Fiber Powder for Gut & Digestive Support

Complete gut coverage. Without the bloat.

  1. Three clinically studied prebiotics — Fibalance™ PHGG, Solnul® RS2, and PreticX™ XOS, each at the dose used in published clinical research*
  2. Triple-Phase Fermentation — Fast (0–12 hr), Steady (12–24 hr), Slow (24–48 hr) — so fermentation is distributed across 48 hours instead of dumped in one spike*
  3. Low-FODMAP certified ingredients — flavorless, grit-free, designed for sensitive digestion*

10 oz · About 30 servings

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Phase Fiber™ delivers complete prebiotic gut support with a clinically designed Triple-Phase Fermentation approach that works throughout the digestive tract.* Featuring Fibalance™ PHGG, Solnul® Resistant Starch, and PreticX™ XOS, this formula helps support digestion, regularity, microbiome health, and daily comfort without the grit or heaviness of many traditional fiber powders.* The flavorless powder dissolves easily into water, coffee, smoothies, and more for convenient daily use.

Triple-Phase Prebiotic Support for Complete Gut & Digestive Health*

  • Supports Healthy Digestion & Regularity*
  • Helps Nourish the Entire Gut Microbiome*
  • Low FODMAP Certified Ingredients
  • Triple-Phase Fermentation: Fast, Steady & Slow
  • Supports Comfort Without Excess Bloating*
  • Flavorless & Easily Mixes into Drinks
  • Fibalance Partially Hydrolyzed Guar Gum (PHGG)
  • Solnul® RS2 Resistant Potato Starch
  • PreticX™ Xylooligosaccharides (XOS)

Mix one scoop daily into 8–12 oz of water, coffee, smoothies, or your favorite beverage. Phase Fiber™ dissolves without changing the taste or texture. If you're new to fiber supplements, start with half a scoop for the first few days, then increase to a full serving.*

Pairs with

Clinically Studied Ingredients

Every scoop delivers the exact doses used in published research.

  • Increase in beneficial bacteria

    Bifidobacterium is a keystone for digestive comfort (Bush et al., 2023)

  • Less fiber needed per dose

    5 g of Fibalance™ PHGG outperforms 30 g of wheat bran (Parisi et al., 2002)

  • Recorded Akkermansia elevation from a prebiotic supplement

    Solnul® RS2 raises the keystone bacterium linked to metabolism and gut barrier health (Bush et al., 2023)
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Why Most Fiber Creates Gas Spikes

Most fiber supplements aren't bad — they're just poorly designed. Single-ingredient fibers ferment all at once within a few hours, hitting your gut with a surge of gas it can't disperse. The problem isn't fiber. It's concentrated fermentation.

Triple-Phase Fermentation solves this by design. PreticX™ XOS ferments Fast (0–12 hr, upper gut). Fibalance™ PHGG ferments Steady (12–24 hr, mid gut). Solnul® RS2 ferments Slow (24–48 hr, deep gut). Fermentation distributed across 48 hours means fewer gas spikes — just steady, complete gut nourishment your body can actually handle.*

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

When Your Gut Works, Everything Works

Four ways Phase Fiber™ supports the complete gut ecosystem.

  • Increases Beneficial Bacteria

    In a published clinical trial, Phase Fiber's prebiotics increased Bifidobacterium by 317% — and produced the highest Akkermansia elevation ever recorded from a prebiotic supplement.*

  • Comfortable Digestion + Regularity

    Distributed fermentation supports daily regularity without the surge of gas and bloating common with single-fiber supplements.*

  • Microbiome Diversity

    Most fibers feed one bacterial family and stop. Phase Fiber feeds five keystone families across three gut regions — the kind of diversity a single-ingredient fiber simply cannot deliver.*

  • A Nourished Gut Lining

    Your gut's protective lining is your body's first line of defense. Phase Fiber reaches the deepest regions where this nourishment matters most — where other fibers never get.*

  • Metabolic Support

    Your metabolism takes its cues from your gut. Phase Fiber's Solnul® RS2 elevates Akkermansia — the keystone bacterium tied to healthy metabolism and gut barrier function — at the clinically studied dose in every scoop.*

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Three Branded Prebiotics, Three Phases of Support

Each ingredient was chosen for where and when it ferments — together they cover all 48 hours.

  • Fast · 0–12 hours · Upper gut

    PreticX™ XOS (Xylooligosaccharides)

    The first phase. PreticX™ XOS ferments quickly in the upper gut, feeding Bifidobacterium where it matters most for early digestive comfort.*

  • Steady · 12–24 hours · Mid gut

    Fibalance™ PHGG (Partially Hydrolyzed Guar Gum)

    The middle phase. Fibalance™ PHGG is so efficient that 5 grams outperforms 30 grams of wheat bran, supporting steady fermentation and microbiome diversity through the mid gut.*

  • Slow · 24–48 hours · Deep gut

    Solnul® RS2 Resistant Potato Starch

    The final phase. Solnul® RS2 reaches the deep gut, producing the highest Akkermansia elevation ever recorded from a prebiotic supplement.*

Timeline based on published clinical research. Individual results may vary.

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

One ingredient or a complete system?

The architecture of your fiber supplement determines everything — coverage, comfort, and results.

Phase Fiber™
Single-fiber supplements
Fermentation window
Up to 48 hours
2–6 hours
Gut coverage
Upper, mid & deep gut
Proximal colon only
Prebiotic blend
Three synergistic prebiotics
One ingredient
Gas production
Steady & dispersed
Concentrated spike
Digestive comfort
Designed for smoother fermentation
Gas spikes more common

Standards Without Compromise

This formula is crafted with thoughtfully selected ingredients and manufactured to rigorous quality standards.

Vegan

Soy
Free

Gluten
Free

Thoughtfully formulated. Independently tested.

We prioritize transparent sourcing, thoughtful formulation, and third-party testing standards to help ensure quality, purity, and consistency across our products.

  • Third-Party Tested

    Third-Party Tested

    Products are independently tested to verify quality, purity, potency, and ingredient standards.

  • Thoughtfully Sourced Ingredients

    Thoughtfully Sourced Ingredients

    We partner with trusted suppliers to select premium ingredients backed by research and rigorous quality standards.

  • Intentional Formulations

    Intentional Formulations

    Every formula is designed for ingredient compatibility, bioavailability, and effective dosing.

  • GMP-Certified Manufacturing

    GMP-Certified Manufacturing

    Manufactured in GMP-certified facilities that follow established quality control standards.

Third-Party Tested
GMP-Certified Facility
Transparent Sourcing
Practitioner-Informed
Quality-Focused

Frequently asked questions

Many fiber supplements ferment too quickly in one area of the gut, creating excess gas and discomfort. Phase Fiber™ was designed differently with Triple-Phase Fermentation — three prebiotic fibers that work Fast, Steady, and Slow throughout the digestive tract. That distribution helps support comfortable digestion and complete gut coverage without the surge of bloating common with traditional fibers.*

It's the clinically designed system behind Phase Fiber™. Instead of a single fiber source, Phase Fiber combines three premium branded prebiotics that ferment at different times across the digestive tract: Fast (0–12 hr, upper gut), Steady (12–24 hr, mid gut), and Slow (24–48 hr, deep gut). The result is more complete microbiome support with steadier digestive comfort.*

Most traditional fibers use a single ingredient that ferments rapidly in one area of the gut. Phase Fiber™ uses three clinically studied prebiotics — Fibalance™ PHGG, PreticX™ XOS, and Solnul® RS2 — for more complete microbiome coverage. It's also made with Low-FODMAP certified ingredients and dissolves easily without grit or heaviness.*

Yes. Phase Fiber™ was formulated with sensitive digestion in mind. Two of three ingredients are Low-FODMAP certified, and Triple-Phase Fermentation helps avoid the rapid fermentation that causes discomfort with many fiber products. The flavorless powder is gentle, easy to mix, and designed for comfortable daily use.*

Add one scoop to 8–12 oz of liquid, then stir or shake. For best results, sprinkle the powder over the liquid (not the reverse), use a shaker bottle or whisk, and avoid hot water — room-temp or cold liquids dissolve the smoothest. Phase Fiber also blends beautifully into smoothies, yogurt, oatmeal, or cold-brew coffee.*

Mix one scoop daily into 8–12 oz of water, coffee, smoothies, or your favorite beverage. Phase Fiber™ dissolves without changing the taste or texture. If you're new to fiber supplements, start with half a scoop for the first few days, then increase to a full serving.*

Yes — prebiotics and probiotics work together. Probiotics introduce beneficial bacteria; prebiotics nourish and support them. Phase Fiber™ pairs especially well with Flora Biome™ as part of a complete gut routine.*

Build Your Complete Routine

Warning: If you have a medical condition or are taking medication, contact a physician before taking this supplement. Keep out of reach of children. *These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

To report a serious adverse event, please contact 844-272-6337.