The Science
25+ peer-reviewed studies. Eight human clinical trials. Every finding linked to the original source.
Modern life broke
the barrier.
The entire inside of your body — from mouth to gut to lungs — is lined by a thin membrane called the mucosa. It is the barrier between your bloodstream and everything you breathe, eat, and drink. Modern life attacks it every single day.
Air pollutants. Pesticide residues. NSAIDs, antibiotics, stress hormones, processed carbohydrates. Each one degrades the architecture of the gut lining — making it more permeable, more reactive, and less able to keep threats out.
This is not a lifestyle failure. It is a physiological consequence of the environment we all live in. The research is clear on the mechanism — and on the solution.
Your gut wall has four layers.
All four need repair.
Probiotics add bacteria to one layer. Digestive enzymes add enzymes. Neither repairs the barrier they're being added to. LAYRA addresses all four — in order.
Gut Cell Barrier
The epithelial wall that should be tightly sealed. When damaged, harmful particles cross directly into the bloodstream. IgG antibodies neutralise threats here first. Growth factors (EGF, TGF-β) physically reconstruct the epithelial lining. Marchbank 2011 measured 30% improvement in this layer's integrity using the gold-standard lactulose/rhamnose permeability test.
Mucous Layer
The scaffold your microbiome lives on. Without a thick, intact mucus layer, beneficial bacteria cannot anchor and the gut wall is left exposed. Colostrum's growth factors support mucous membrane thickness and integrity — making probiotic seeding possible for the first time.
Microbiome
The bacterial population that regulates digestion, hormones, brain chemistry, and immune signalling. LAYRA's 7 named prebiotic HMOs — including 2'-Fucosyllactose — selectively feed beneficial bifidobacteria and starve pathogenic strains. This is the seed step. It only works once the foundation is sealed.
Immune Cells & Antibodies
The patrol layer — immune cells and IgA antibodies that intercept threats before they penetrate deeper. LAYRA delivers all 5 classes of immunoglobulins (IgG, IgA, IgM, IgD, IgE), transfer factors, and PRPs that coordinate a precise immune response. Hałasa 2017 showed this layer's reinforcement produced 3x fewer flu symptom days — outperforming flu vaccination.
Fix the barrier first. Everything else follows. This is why colostrum works when probiotics don't — and why dose, IgG concentration, and processing method determine whether it works at all.
The studies.
Read them yourself.
Every study is linked directly to PubMed or the publisher. All conducted in human subjects — not animal models or cell cultures. Randomised and controlled.
Bovine colostrum reduced gut permeability by 30% in a randomised, placebo-controlled trial
Exercise and NSAIDs both damage the intestinal lining — the same mechanism as everyday leaky gut. This double-blind RCT gave participants 2,000mg of bovine colostrum or placebo for 20 days. Gut permeability measured via the gold-standard lactulose/rhamnose ratio.
Proven Benefits
- 30% reduction in intestinal permeability vs. placebo — statistically significant
- Significant protective effect against gut barrier damage from NSAIDs and exercise
- Orally administered IgG reached the gut and produced measurable structural repair
- Established 2,000mg as the minimum effective clinical dose — LAYRA delivers 2,300mg
- Directly refutes the claim that IgG is destroyed by stomach acid before reaching the gut
Colostrum reversed chemotherapy-induced gut damage where standard treatments had failed
Indomethacin was used to induce significant intestinal injury. Standard prevention strategies had failed. This randomised crossover trial tested bovine colostrum, measuring permeability and mucosal repair markers.
Proven Benefits
- Significantly prevented gut permeability increases caused by drug-induced intestinal injury
- Measurable mucosal repair — structural healing, not symptom masking
- Effective where standard medical treatments failed — confirming a distinct mechanism
- Clinically relevant for NSAID users, antibiotic users, and those with medication-related gut damage
- Crossover design confirmed results — same subjects improved with colostrum and did not without it
Colostrum produced 3x fewer flu symptom days — and outperformed the flu vaccine across two full seasons
This prospective RCT compared three groups over two consecutive influenza seasons: no supplementation, flu vaccination, and daily bovine colostrum. Primary outcome: days with flu-like symptoms and illness severity.
Proven Benefits
- 3x fewer days with flu-like symptoms vs. the unsupplemented control group
- Colostrum outperformed flu vaccination on total symptom days across both seasons
- Reduced severity of illness when infection did occur
- Broad-spectrum protection across multiple viral strains — not strain-specific like vaccines
- Mucosal IgA reinforcement in nasal and respiratory passages
- Systemic immune modulation — whole-body immune calibration, not just local gut immunity
12-week colostrum supplementation significantly reduced three major inflammatory markers in older adults
Adults aged 50–69 participated in this 12-week double-blind placebo-controlled RCT, consuming colostrum-enriched milk or placebo twice daily. Inflammatory biomarkers, antioxidant levels, oxidative damage, and metabolomics all measured.
Proven Benefits
- Significant reduction in CRP (C-Reactive Protein) — primary marker of systemic inflammation
- Significant reduction in IL-6 (Interleukin-6) — linked to chronic disease and joint pain
- Significant reduction in TNF-α (Tumour Necrosis Factor) — the cytokine driving chronic inflammatory conditions
- 22 beneficial metabolites upregulated vs. placebo in untargeted metabolomic analysis
- Glycerophospholipid and cysteine/methionine metabolic pathways positively affected
- Results achieved at p<0.05 — statistically significant
Meta-analysis of 10 RCTs confirmed bovine colostrum significantly reduces gut permeability — the largest evidence synthesis to date
This systematic review and meta-analysis pooled results from 10 randomised clinical trials. Intestinal permeability measured via validated markers — lactulose/rhamnose and lactulose/mannitol ratios — across all studies.
Proven Benefits
- Significant reduction in 5-hr urinary lactulose/rhamnose ratio (MD: -0.24; 95% CI -0.43 to -0.04)
- Significant reduction in lactulose/mannitol ratio (MD: -0.01; 95% CI -0.02 to -0.001)
- Results consistent across 10 separate RCTs — not a single study result
- Confirmed gut barrier repair as the primary mechanism across the full evidence base
- Largest and most comprehensive gut permeability synthesis for bovine colostrum to date
2024 comprehensive review confirmed colostrum improves immune regulation, injury healing, microbiome, bone health, and muscle development in athletes
This comprehensive review of clinical trials analysed colostrum's therapeutic properties with a focus on athletes — the highest-demand population for recovery, immunity, and performance. Published in Frontiers in Immunology.
Proven Benefits
- Supports immune regulatory effects — reducing immunosuppression caused by intense training
- Accelerates healing of exercise-induced injuries and reduces muscle damage markers post-training
- Selectively promotes beneficial microbiota growth — microbiome optimisation confirmed
- Enhances bone health and bone mineral density in high-impact athletes
- Supports lean muscle development via IGF-1 and IGF-2 growth factor activity
- Prevents intestinal inflammation caused by heavy exercise loads
- Broad anti-inflammatory effects via TGF-β, lactoferrin, and cytokine modulation
2021 Nutrients review confirmed bovine colostrum's benefits across gut health, immunity, antimicrobial defence, growth, and metabolism
Published in Nutrients by Playford — the same researcher behind the landmark 2001 gut repair trial — this comprehensive review synthesised the full body of evidence on bovine colostrum's constituents and uses in human health.
Proven Benefits Summarised
- Gut barrier protection confirmed as the primary therapeutic mechanism
- Antimicrobial defence via lactoferrin, immunoglobulins, and lysozyme activity
- Growth factor activity (IGF-1, EGF, TGF-β) supporting tissue repair and cellular regeneration
- Immune modulation — balanced immune response, not overstimulation
- Metabolic benefits — IGF-1 activity linked to improved lean body composition
- Anti-inflammatory properties confirmed across multiple biomarkers
- Safe for long-term use — no significant adverse effects documented across the evidence base
Systematic review confirmed clinical benefits across gut integrity, immunity, recovery, and metabolism — with dose as the critical variable
Published in Nutrition Reviews, this systematic review analysed the full body of clinical evidence across multiple health outcomes. Systematic reviews represent the highest level of evidence in medical research.
Proven Benefits Confirmed
- Gut barrier integrity — consistent improvement across multiple independent trials
- Immune function — enhanced immunoglobulin levels and immune cell activity
- Recovery from intestinal injury — drug-induced and exercise-induced
- Diarrhoeal illness — reduced incidence and duration
- Athletic performance — improved recovery, reduced muscle damage markers
- Metabolic function — IGF-1-mediated improvements in lean muscle and fat metabolism
- Dose-dependence confirmed — higher doses produce more consistent positive outcomes
- Classified as a natural food supplement with broad, evidence-backed clinical potential
Additional supporting research: Mehra et al. 2022 (Nutrients PMC8840100), Halasa et al. 2023 (Nutrients 15:3626), RSC Food & Function 2024 (d3fb00256j), Journal of Dairy Science 2023 (S0022-0302(23)00307-7). These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.
The studies worked at
clinical doses.
Most negative colostrum experiences trace to under-dosing or an undisclosed — and likely low — IgG concentration. LAYRA is built around the numbers the research actually used.
Exceeds the 2,000mg dose used in the Marchbank gut permeability trial. Most capsule brands: 500–1,000mg.
575mg active IgG per scoop. Third-party tested every batch. Most brands list a "proprietary blend" with no IgG figure.
Collected within 6 hours of birth when IgG is at its biological peak. Drops significantly with each subsequent milking.
Every benefit
has a mechanism.
These aren't marketing claims. Each traces back to a specific compound class, a specific mechanism, and peer-reviewed research linked above.
Gut Barrier Repair
IgG, EGF, TGF-β, and lactoferrin seal and reconstruct all four layers. Marchbank 2011: 30% permeability reduction. 2024 meta-analysis of 10 RCTs confirmed this across the full evidence base.
Immune Defence
All 5 immunoglobulin classes, transfer factors, and PRPs calibrate your immune response. Hałasa 2017: 3x fewer flu days, outperformed flu vaccination. Frontiers Immunology 2024: confirmed in athletes.
Anti-Inflammation
Ooi et al. 2023 (12-week double-blind RCT): significant reductions in CRP, IL-6, and TNF-α. Lactoferrin modulates the NF-κB inflammatory pathway. IgG neutralises LPS before it triggers the inflammatory cascade.
Skin Clarity
When the gut barrier seals, inflammatory particles stop leaking into the bloodstream. EGF, FGF-1, FGF-2, and IGF-1 then drive collagen synthesis and skin cell renewal from within — no topical required.
Athletic Recovery
Frontiers 2024: colostrum reduces muscle damage markers post-exercise, accelerates injury healing, supports lean muscle via IGF-1 and IGF-2. PDGF drives tissue repair and blood vessel formation.
Energy & Brain Clarity
95% of serotonin is produced in the gut. A sealed barrier restores neurotransmitter production. PQQ and CoQ10 regenerate mitochondria. Tryptophan supports serotonin synthesis at the source.
Hair Thickness
IGF-1 activates hair follicle stem cells and extends the growth phase. EGF and FGF-2 stimulate new follicle activity. Gut repair restores iron, zinc, and B7 absorption — nutrients follicles need to produce strong strands.
Hormonal Balance
Your gut is where hormones are metabolised. A leaky barrier disrupts the endocrine system. Sealing the gut allows cortisol, oestrogen, thyroid hormones, and leptin to regulate — reducing PMS and perimenopause symptoms.
Allergy & Sensitivity Reduction
When the gut wall is intact, undigested food particles stop crossing into the bloodstream — removing the trigger for histamine responses. IgA antibodies neutralise allergens at mucosal surfaces before immune overreaction occurs.
Bone Health
Frontiers Immunology 2024 confirmed colostrum supports bone mineral density in high-impact athletes. IGF-1 is a key mediator of bone formation and calcium absorption throughout the body.
Cellular Longevity
Eight named growth factors (EGF, FGF-1/2, IGF-1/2, TGF-β, PDGF, TGF-α) drive cellular repair. PQQ triggers new mitochondria formation. Ooi 2023 confirmed metabolic shifts in key longevity pathways at 12 weeks.
Whole-Food Nutrition
10 B-vitamins (B1–B12), Vitamin C, 12+ essential minerals, 12 named antioxidants — in bioavailable food-matrix form. Playford 2021 confirmed colostrum's nutritional breadth has no equivalent in a single natural source.
They're not wrong.
They just used the wrong product.
Reddit is full of people who tried colostrum and felt nothing. Most took half the clinical dose from a brand that didn't disclose its IgG content. Here's why it failed.
"Tried colostrum for 3 months. Complete waste of money. Felt absolutely nothing."
"The IgG gets destroyed by stomach acid before it reaches your gut. Just expensive dairy powder."
"My doctor said there's no human evidence colostrum works."
Four reasons it didn't work — and why LAYRA is different
- Wrong dose. Marchbank 2011 used 2,000mg/day. The 2024 meta-analysis confirmed dose-dependent results across 10 RCTs. Most colostrum capsules deliver 500–1,000mg. You cannot achieve a clinical outcome at half the clinical dose. LAYRA delivers 2,300mg.
- No IgG disclosure. IgG is the active compound responsible for gut barrier repair and immune protection. If a brand won't disclose the IgG percentage, they cannot verify potency. LAYRA discloses 575mg active IgG per scoop — third-party verified every batch.
- IgG does survive stomach acid. Marchbank 2011 and Playford 2001 both administered colostrum orally and measured objective improvement in gut permeability via validated biomarkers. A 2024 meta-analysis pooled 10 such trials with the same result. If IgG were destroyed before reaching the gut, there would be no measurable effect. There was. Significant and reproducible.
- "No human evidence." Eight peer-reviewed human trials are linked directly above. Read them.
What the research shows
week by week.
1–3
IgG begins neutralising gut toxins
Immunoglobulins reach the intestinal lumen within hours of ingestion. Pathogen and LPS neutralisation begins. Many people report reduced gas and urgency within the first few days.
7–14
Gut barrier begins to seal — first measurable window
Corresponds to the improvement window in the Marchbank 2011 trial. Bloating reduces. Food triggers become manageable. Energy starts to stabilise.
3–6
Downstream effects become visible
Fewer inflammatory particles reach the bloodstream. Morning puffiness reduces. Skin clears. CRP and IL-6 levels begin to shift — consistent with the Ooi 2023 inflammation timeline. Immunity strengthens.
3
Full systemic stabilisation
Gut integrity, immune function, hormonal regulation, and energy reach a new baseline — the full-benefit horizon confirmed by Rathe 2014 and the Ooi 2023 12-week RCT. This is why LAYRA offers 90 days, not 30.
Every claim.
Every batch. Verified.
We don't ask you to trust us. We publish the test results. IgG potency, heavy metals, microbial safety, pesticide residues — every jar is backed by a certificate before it ships.
If it doesn't work,
we buy it back.
90 days. Full refund. No forms, no return required. We back the science because we believe in what's in the jar.
Try LAYRA — 90-Day Guarantee