Within™ Probiotic 40B

Within™ Probiotic 40B

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Within™ Probiotic 40B
Within™ Probiotic 40B

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Within™ Probiotic 40B

As estrogen declines, your gut microbiome changes—disrupting the bacterial balance that helps metabolize hormones, regulate metabolism, and support mood. Within™ Probiotic 40B delivers 40 billion...

  • Free 2-day shipping
  • 30-day money-back guarantee
  • HSA/FSA eligible
Key Benefits

Key Benefits

Key Benefits
Supports:
  • Gut microbiome support during hormonal transition
  • Digestive wellness and healthy metabolic function
  • Gut-brain support and a healthy response to everyday stress
  • Digestive comfort and a balanced intestinal microbiome
  • Healthy digestion and nutrient utilization
WHY IT WORKS:

Changing estrogen levels may influence the composition and function of the gut microbiome. Within™ Probiotic 40B combines four researched probiotic strains with a prebiotic to support microbial balance, digestive comfort, and the gut-brain connection during hormonal transition.

Why Gut Health Matters More During Hormonal Transition

Why Gut Health Matters More During Hormonal Transition

During perimenopause and menopause, changing estrogen levels may influence the composition and function of the gut microbiome.

Your gut microbiome contributes to:

  • Participating in estrogen metabolism through microbial enzymes associated with the “estrobolome”
  • Participating in metabolic processes
  • Supporting communication along the gut-brain axis
  • Supporting nutrient absorption and energy production
  • Interacting with immune and inflammatory pathways
Why Gut Health Matters More During Hormonal Transition

Research suggests that menopause may be associated with changes in gut microbial composition and function, although the pattern and significance of those changes vary among women.

  • Hot flashes and night sweats
  • Weight gain (especially abdominal)
  • Mood swings, anxiety, and irritability
  • Bloating and digestive discomfort
  • Energy crashes and brain fog

Hormonal transition can coincide with changes in microbial balance, digestion, and overall gut function—even when your daily habits have not changed.

Fermented foods can contribute beneficial microorganisms, but they do not consistently provide the identified strains or standardized CFU levels found in a formulated probiotic supplement.

What’s Inside

What’s Inside

Each 2-capsule serving provides 40 billion CFU of clinically-studied probiotic strains using MAKTREK® Bi-Pass Technology:

  • Lactobacillus acidophilus (La-14): Supports digestive and intestinal microbial balance.
  • Bifidobacterium lactis (Bl-04): Supports a balanced intestinal microbiome and digestive wellness.
  • Lactobacillus plantarum (Lp-115): Supports digestive health and a balanced intestinal environment.
  • Lactobacillus paracasei (Lpc-37): Supports the gut-brain connection and a healthy response to everyday stress.
  • Complex Marine Polysaccharide (60mg): Helps protect probiotic organisms as they move through the digestive tract.
  • Fructooligosaccharide (24mg): A prebiotic fiber that helps nourish beneficial gut bacteria.
  • Other ingredients: Hypromellose (capsule), rice maltodextrin, L-Leucine.
What’s Inside
Why these four strains specifically?

Why these four strains specifically?

Why these four strains specifically?

Probiotic benefits are strain-specific, which makes clear strain identification important.

Within™ combines four identified probiotic strains selected to support:

  • Digestive and intestinal microbial balance
  • Digestive comfort
  • The gut-brain connection
  • A healthy response to everyday stress
  • A balanced intestinal environment

The strains matter more than the CFU count. These four strains provide complementary support for digestive wellness, microbial balance, and gut-brain communication.

Why Within™ Probiotic 40B

Not all probiotics are created equal—especially for hormonal transitions.

Within™ Probiotic 40B:

  • Four identified probiotic strains with strain-specific research
  • 40 billion CFU per serving 
  • Shelf-stable (no refrigeration required) 
  • No magnesium stearate or artificial ingredients
  • Every batch independently laboratory tested
  • NSF-certified facility

vs. Generic Probiotics

  • Random strains for "general health"
  • May not identify the specific strains or provide research associated with those strains
  • Often require refrigeration 
  • Inconsistent potency 
  • May contain unnecessary fillers

Who This Is For

Within™ Probiotic 40B is designed
for women who:

  • Want targeted microbiome support during perimenopause or menopause
  • Experience occasional bloating or digestive discomfort
  • Want to support digestive regularity and microbial balance
  • Are interested in supporting the gut-brain connection
  • Prefer clearly identified probiotic strains
  • Value third-party testing and transparent formulation

How to Take

How to Take

Serving: 2 capsules daily

Timing: For best results, take one (1) capsule during the day and one (1) capsule in the evening.

Sensitive? Start with one (1) capsule daily for the first 3–7 days, then increase to two (2).

Can be taken alone or as part of the Women's Health Collection for comprehensive hormonal, metabolic, and nervous system support.

How to Take

Product Details

  • 60 capsules per bottle
  • 30 servings (1-month supply)
  • Delayed-release vegetarian capsules
  • No refrigeration required
  • 3-year shelf life
  • Free from:
    Gluten Lactose Corn GMOs
    Gluten Lactose Corn
    GMOs Added Sugar
    Added Sugar Artificial Ingredients
    Artificial Ingredients
Quality & Testing

Quality & Testing

Quality & Testing
Every batch independently laboratory tested for:
  • Heavy metals (lead, mercury, arsenic, and cadmium)
  • Microbiological quality, including testing for E. coli, Salmonella, Staphylococcus aureus, coliforms, yeast, and mold
  • Finished-product identity
  • Capsule appearance and fill-weight consistency

Manufactured in NSF-registered, GMP-certified, FDA-registered facilities in the USA.

Certificate of Analysis available for every batch.

Quality & Testing

What Many Women Notice

Probiotic responses vary from person to person. With consistent use, some women may notice changes in digestive comfort and regularity as the formula supports a balanced intestinal microbiome.

Weeks 3–7 Within 3–7 Days

Reduced bloating, more comfortable digestion

Weeks 2–4 Weeks 2–4

Hot flash frequency begins to decrease, mood feels more stable

Weeks 4–8 Weeks 4–8

Noticeable improvements in energy, sleep quality, and temperature regulation

Weeks 2–4 Weeks 2–4

Hot flash frequency begins to decrease, mood feels more stable

Months 2–3 Months 2–3

Weight stabilizes, clothes fit better, sustained improvements in all symptoms

Consistency matters. Your gut microbiome is rebuilding—not just getting a temporary boost.

The Science Behind Within™ Probiotic 40B

The Science Behind Within™ Probiotic 40B

Research suggests that the gut microbiome and estrogen metabolism influence one another, and scientists are continuing to study how probiotic and prebiotic interventions may support women during and after the menopause transition.

— The Journal of The Menopause Society, 2024

The gut microbiome's role in estrogen metabolism—known as the estrobolome—becomes increasingly important during hormonal transitions. Gut microorganisms participate in estrogen metabolism through microbial genes and enzymes collectively described as the estrobolome.

— Frontiers in Global Women’s Health, 2023

Women experiencing perimenopause and menopause show decreased populations of beneficial Lactobacillus and Bifidobacterium species. Researchers are continuing to investigate whether targeted microbiome support can influence menopause-related health outcomes.

— American Journal of Clinical Nutrition, 2024

Questions?
We’ve got answers.

Many women notice reduced bloating within 3-7 days. Hot flash reduction typically begins in weeks 2-4. Full benefits develop over 8-12 weeks as your gut microbiome rebalances. Physical changes (weight, body composition) often take 2-3 months of consistent use.

2 capsules once daily, preferably with breakfast or your first meal. The delayed-release capsules protect bacteria through stomach acid, so they reach your gut intact. If you're sensitive to new supplements, start with 1 capsule for the first 3-7 days, then increase to 2.

Yes. These are beneficial bacteria your body naturally needs. Long-term use is safe and actually more effective as your microbiome stabilizes over time. Many women take this indefinitely as foundational support.

Generally safe with most medications. Consult your doctor if you're on immunosuppressants. If taking antibiotics, take probiotics 2+ hours apart. Can be taken safely with HRT (hormone replacement therapy).

Most drugstore probiotics use random strains for "general gut health" with no research on hormonal symptoms. Within™ contains six specific strains clinically studied for their effects on estrogen metabolism, weight management, hot flashes, and mood during menopause. The strains matter more than the CFU count.

No. Our delayed-release technology keeps bacteria viable at room temperature through the expiration date. This makes it convenient for travel and ensures consistent potency.

Yes. Many women take this alongside our Magnesium Glycinate and Berberine as part of the Women's Health Collection for comprehensive hormonal, metabolic, and nervous system support. It works synergistically with most supplements.

Some people experience mild digestive adjustment (gas, bloating, or changes in bowel movements) when introducing probiotics. This typically resolves within 3-7 days as your gut adapts. Start with 1 capsule daily for the first week, take with food, and increase gradually. If symptoms persist beyond one week, pause and consult your healthcare provider.

Yes. Every batch is third-party tested to USP standards for potency, strain identity, heavy metals, and microbial contamination. Heavy metals consistently test below detectable limits. Certificate of Analysis available for each batch.

30-day money-back guarantee on your first order. If you don't notice improvements, contact us for a full refund (less $5 handling + shipping). No questions asked.

Most Women Take This as Part of a Coordinated System

Most Women Take This as Part of a Coordinated System

Within™ Probiotic 40B works well on its own—but many women find it works even better as part of the Women's Health Collection, which adds:

  • Magnesium Glycinate for nervous system regulation, sleep quality, and muscle relaxation
  • Berberine for metabolic balance, blood sugar support, and weight management

Together, these three supplements address the gut-hormone connection, metabolic changes, and nervous system dysregulation that happen simultaneously during perimenopause and menopause.

Most Women Take This as Part of a Coordinated System
Learn more about the Collection

Try it for 30 days.
If it's not right for you, we'll refund your first order—no hassle.

Try it for 30 Days

Try it for 30 Days

If it's not right for you, we'll refund
your first order—no hassle.

Support your gut-hormone balance with the specific strains this phase of life requires.

supplement

Start with a 30-day supply. If it's not right for you, we'll refund it—no questions asked.

  • Free 2-day shipping
  • 30-day money-back guarantee
  • HSA/FSA eligible