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You're not broken. Your immune system isn't defective. The supplements you tried couldn't work because they ignored where 70% of immunity lives: your gut.

Immune Fortress rebuilds immune protection at the source. You can stop dreading every cough and sniffle around you.

90-Day Money-Back Guarantee
Try Immune Fortress risk-free for 90 days. If you don't experience fewer infections, better recovery, and the protection we describe, we'll refund every penny.

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1. Seal Your Gut Barrier Where 70% of Immunity Lives

You recognize the pattern: you catch everything going around. A coworker gets sick Monday, you're down by Friday. Your kids bring home a cold, you're in bed with it by Sunday.

Seventy percent of your immune system lives in your gut, behind a barrier that should keep threats out. When that barrier has gaps, pathogens slip through and your immune system stays on constant alert.

Immune Fortress seals the gaps first, then strengthens your defense. Five clinically-backed ingredients work together: colostrum immunoglobulins seal breaches(1), tributyrin provides fuel for barrier cells, beta-glucan trains your immune cells(2), bacteriophages clear problematic bacteria, spore-forming probiotics restore balance(3).

You can walk through the grocery store, attend your kid's basketball game, and live normally—without constant anxiety about getting sick. No more mental calculations about exposure risk.

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2. Rebalance Your Microbiome for Clear Immune Signaling

When you catch every cold and take forever to recover, your microbiome is sending confused signals. The good bacteria that should be training your immune cells are outnumbered by problematic species.

FortiPhage™ bacteriophages selectively clear harmful bacteria without disturbing the beneficial ones(5). LactoSpore® Bacillus coagulans—clinically shown to reduce respiratory infections by 31% in children—establishes populations of immune-supportive bacteria(3). Polyphenols from berries feed beneficial species(4).

Your immune system can tell friend from foe again. You stop catching everything that walks past your cubicle.

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3. Train Your Immune Cells to Respond Faster

That first throat tickle. You know what's coming: two days until you're down for a week. Your immune system isn't weak—it's just responding too slowly to stop infections before they take hold.

When your innate immune system is properly trained, it neutralizes threats before symptoms take hold. That's the window we're targeting: before you miss work, cancel plans, or spend three days in bed.

Wellmune® beta-glucan reduced upper respiratory symptoms by 58% in stressed adults and cut post-exercise infections by 40% in athletes(2). Lactoferrin blocks viral and bacterial attachment, reducing infection incidence by 22% in clinical trials(6).

Together, they train your immune cells to recognize threats the first time they're encountered. You stop getting hit harder and longer than everyone around you.

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4. Experience Fewer Sick Days and Faster Recovery

Clinical trials demonstrate 30-62% fewer respiratory infections across all populations(7, 8, 9, 10). Children experience 31% fewer symptom days and 50% fewer antibiotic prescriptions(7). Athletes see 40% fewer post-exercise infections(2).

When you do catch something, it's 3-4 days of mild symptoms instead of two weeks of misery. You maintain your schedule instead of calling in sick for a week.

This is what happens when all three systems work together—sealed gut barrier, balanced microbiome, trained immune cells. You're not just surviving each season anymore. You're living normally.

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5. Build Year-Round Protection That Lasts Beyond Cold Season

The first four benefits give you immediate protection. This one is about lasting resilience—not just surviving this season, but thriving year-round.

With consistent use, your baseline shifts. You're no longer the first person in the office to get sick. You can travel, attend crowded events, go to the gym without calculating exposure risk.

The research confirms this isn't temporary relief: infection rates dropped from 48% to 32% in just 7 weeks(8). Over 20 weeks in children, symptom days decreased by 31%(7).

Colostrum's growth factors repair intestinal barriers(1). Spore-forming probiotics establish populations that persist(3). Beta-glucan's immune-priming effects last 4-6 weeks even after stopping supplementation(2).

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Why Immune Fortress Exists

For 15 years, I treated thousands of patients struggling with frequent infections, post-viral fatigue, and immune challenges in my functional medicine practice. They'd already tried the conventional approach: vitamin C, zinc, elderberry, echinacea. Some were spending $150-250/month on immune supplements without meaningful protection.

The issue was clear: immune supplements couldn't work while the foundation was compromised (the gut barrier where 70% of immune function originates).

I'd review patient charts and see the same pattern: compromised gut integrity, imbalanced microbiome, sluggish immune signaling. No amount of vitamin megadosing could compensate for a compromised barrier.

So I created the protocol I used successfully in my practice: seal the gut barrier with colostrum and tributyrin, rebalance the microbiome with bacteriophages and spore-forming probiotics, train immune cells with beta-glucan and lactoferrin.

That protocol became Immune Fortress. It's not about boosting immunity. It's about supporting it at the source.

— Chris Kresser, Founder, Adapt Naturals

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Why You Can Trust Immune Fortress

Third-Party Lab-Tested with Transparent Results
We conduct third-party testing on all our products to verify their purity, potency, and safety. We share these results by posting Certificates of Analysis (CoAs) and test results on our website.

You can verify exactly what's in your bottle. No hidden fillers. No contaminants. No surprises.
See Test Results

Clinical Doses of Research-Backed Ingredients
Every ingredient in Immune Fortress is included at the exact clinical dose shown effective in research:

Wellmune® beta-glucan (200mg): The extract used in 15+ clinical trials showing 40-58% reduction in respiratory symptoms across multiple populations
Grass-fed colostrum (2.5g): 2.5x more than most competitors, matching the 2g+ dose used in studies showing 36-57% reduction in infections
Lactoferrin (100mg): Far higher than the 3-5mg naturally present in colostrum, providing the 22% infection reduction shown in clinical trials
LactoSpore® Bacillus coagulans (2 billion CFU): Spore-forming probiotic proven to reduce respiratory infection symptoms in children
CoreBiome® tributyrin (300mg): Clinically-studied dose for gut barrier support
FortiPhage™ bacteriophages (15mg): Next-generation prebiotic effective at fractions of traditional prebiotic doses

No proprietary blends. No "fairy dusting." Complete transparency.

You're getting the exact compounds used in the research studies, not cheaper substitutes.

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90-Day, Zero-Risk, Zero-Hassle Guarantee

90

90 Full Days to Transform - Zero Risk

Take Immune Fortress for 90 days. If you don't experience fewer infections, faster recovery, or the protection we've described, we'll refund every penny, including the bottles you've already taken.

You don't even need to return the product. Just contact us.

Fifteen years of clinical observations with thousands of patients showed this gut-based approach works when you support all three systems: gut barrier integrity, microbiome balance, and immune cell training.

Your safety and satisfaction are what matter. We'll cover the risk.

HERE'S HOW IT WORKS:

No return shipping needed - Keep the products
Refund within 24 hours - Just one email
No forms or phone calls - Simple and respectful

Your Two-Formula Immune Restoration System

BIOME PROTECT
Optimizes the Gut-Immune Axis


✓ Removes harmful bacteria with bacteriophages
✓ Spore-based probiotics that survive stomach acid
✓ Bioavailable butyrate to strengthen gut barrier
✓ Polyphenols for antimicrobial support

Daily Dose: 2 capsules with meals

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BIO-AVAIL COLOSTRUM+
Arms Your Immune Defenses


✓ 2.5g colostrum per serving (2.5x competitors)
✓ 25% immunoglobulins for immune protection
✓ 100mg lactoferrin to block pathogens
✓ 250mg Wellmune® beta-glucan to train immune cells

Daily Dose: 1 scoop in water, smoothie, or mixed with food

Why You Need Both:

One optimizes where immunity lives (your gut). One arms your defenders (immune cells).
Skip one and you're only addressing half the problem.

Full Transparency: We post our Certificates of Analysis (COAs) online for every batch. View test results at adaptnaturals.com/coa

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Frequently Asked Questions

Those didn't work because your gut barrier had gaps. No amount of supplementation can work when the foundation is compromised.

Immune Fortress rebuilds the foundation first—sealed gut barrier, balanced microbiome, trained immune cells—so your body can use what you give it. That's why patients who failed with everything else finally see protection.

This isn't another supplement to try. This is what finally works.

Most immune supplements try to "boost" immunity with megadoses of vitamins. Immune Fortress supports immunity at its source: the gut-immune axis.

The difference:
• Other supplements: High-dose vitamin C, zinc, elderberry (addressing symptoms)
• Immune Fortress: Colostrum, beta-glucan, bacteriophages, tributyrin (addressing foundations)

We're supporting the 70% of your immune system that lives in your gut, where immunity originates. When you repair the gut barrier, rebalance the microbiome, and train immune cells, the results are lasting.

Most people notice they're avoiding infections within the first month, with continued improvement over 2-3 months. Research shows the strongest protection develops between weeks 4-8.

Some ingredients work immediately (colostrum immunoglobulins start on day one), while others build over time (your microbiome rebalances fully in 4-8 weeks).

That's why we offer a 90-day guarantee—so you can experience the full transformation.

Immune Fortress is safe to combine with most supplements. However, we recommend consulting your healthcare provider if you have any questions or concerns about interactions with prescription medications, especially immunosuppressants or blood thinners.

If you're currently taking vitamin C, zinc, or elderberry, you can continue them alongside Immune Fortress or discontinue them after 4-6 weeks once your gut-immune axis is restored.

What makes us different:

• Complete transparency: We list exact doses and use clinically-studied ingredients (Wellmune®, LactoSpore®, CoreBiome®, FortiPhage™)
• Third-party testing: We publish Certificates of Analysis on our website showing purity and potency
• Real clinical research: 20+ peer-reviewed studies back these ingredients at these doses
• 90-day guarantee: We'll refund you even if you've taken the entire supply
• 15 years clinical experience: Chris Kresser created this based on treating thousands of patients with immune challenges

You don't have to take our word for it. Try it for 90 days. If you're not getting sick less often, we'll refund every penny.

Because we use therapeutic doses of clinically-proven ingredients rather than vitamins that can't work when your gut barrier isn't sealed.

Compare:
• Generic vitamin C + zinc: $20-30/month (doesn't address gut barrier)
• Wellmune® beta-glucan: Pharmaceutical-grade beta-1,3/1,6 glucan used in clinical research showing 58% reduction in symptoms
• Bio-Avail Colostrum+: 2.5g whole colostrum (2.5x more than competitors) plus 100mg lactoferrin and 200mg beta-glucan
• LactoSpore® Bacillus coagulans: Spore-forming probiotic that survives digestion, clinically shown to reduce respiratory infections
• FortiPhage™ and CoreBiome®: Next-generation prebiotics and postbiotics that work at fractions of traditional doses

The difference in effectiveness is substantial. We'd rather create a system that prevents illness than inexpensive vitamins that don't address the foundation.

When you factor in fewer sick days, fewer doctor visits, and fewer missed obligations, Immune Fortress pays for itself within a single avoided illness.

Need Personal Help?

Email us directly: support@adaptnaturals.com
We typically respond within 3 hours during business hours (9am-5pm EST)

"We take pride in 'white glove' service. If you have any questions or concerns, just ask. We're happy to help!"
— Chris Kresser

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Ready to Stop Living in Fear of Getting Sick?

You understand that immunity doesn't come from megadosing vitamins. It comes from rebuilding the foundation—sealed gut barrier, balanced microbiome, trained immune cells.

Single-ingredient supplements couldn't fix all three. Immune Fortress does.

You're getting a comprehensive approach backed by clinical research and 15 years of functional medicine experience. Complete transparency about what's inside and why. And a 90-day guarantee that covers the risk entirely.

Try it for 90 days, completely risk-free. If you're not experiencing fewer sick days, better energy, and the protection you need, we'll refund every penny. No returns necessary. No questions asked.

Your search for real protection ends here. You don't have to keep canceling plans, missing work, and living with anxiety about every cough and sniffle around you.

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REFERENCES

  1. Hałasa M, Maciejewska D, Baśkiewicz-Hałasa M, et al. (2022). The effect of bovine colostrum supplementation in adults: a systematic review and meta-analysis of randomized controlled trials. Front Nutr, 9:1003560.

  2. Talbott SM, Talbott JA. (2010). Effect of BETA 1, 3/1, 6 GLUCAN on Upper Respiratory Tract Infection Symptoms and Mood State in Marathon Athletes. J Sports Sci Med, 9(4):509-15.

  3. Anaya-Loyola MA, Enciso-Moreno JA, López-Ramos JE, et al. (2019). Bacillus coagulans GBI-30, 6086 modifies the incidence of respiratory infections in children attending day-care centres: a randomised, controlled trial. Benef Microbes, 10(4):469-478.

  4. Wan MLY, Co VA, El-Nezami H. (2021). Dietary polyphenol impact on gut health and microbiota. Crit Rev Food Sci Nutr, 61(4):690-711.

  5. Majewska J, Beta A, Lecion D, et al. (2023). Oral Application of Phage Encapsulated in Alginate/CaCO3 Microparticles to Treat Infections in the Gastrointestinal Tract. Molecules, 28(15):5604.

  6. Ochoa TJ, Pezo A, Cruz K, et al. (2015). Clinical studies of lactoferrin in children. Biochem Cell Biol, 90(3):457-67.

  7. Hałasa M, Maciejewska D, Ryterska K, et al. (2023). The Effect of Colostrum Bovinum Supplementation on the Duration and Incidence of Upper Respiratory Tract Infections in Children Aged 4–10 Years: A Randomised Controlled Study. Nutrients, 15(8):1882.

  8. Jones AW, Cameron SJ, Thatcher R, et al. (2016). Effects of bovine colostrum supplementation on upper respiratory illness in active males. Brain Behav Immun, 39:228-35.

  9. Brinkworth GD, Buckley JD. (2003). Concentrated bovine colostrum protein supplementation reduces the incidence of self-reported symptoms of upper respiratory tract infection in adult males. Eur J Nutr, 42(4):228-32.

  10. Talbott SM, Talbott JA. (2012). Baker's yeast beta-glucan supplement reduces upper respiratory symptoms and improves mood state in stressed women. J Am Coll Nutr, 31(4):295-300.