The Silent Theft of Bifidobacteria: How Glyphosate and Vaccines May Be Robbing Our Children's Neurological Future

PART 1: A Pediatrician's Hypotheses Exploring the Collateral Damage to the Infant Gut Microbiome, the Acetylcholine Connection, and the Exploding ADHD Epidemic: A Plea to Look Under the Carpet

The Bifidobacteria Crisis: What 25% of Babies Are Already Missing: Part I

Part I of this series will review what we know, why we know it, mechanisms of injury, and an extensive reference list to support my arguments.

Part II will explore the available solutions necessary to save our children from an impaired and/or unhealthy neurologic future. An extensive reference list will be provided.

Part III will discuss the call to action to local, state, and governmental agencies to prevent further harms to our most precious and under-protected members of our society.

I have to decided to write this ‘white paper’ as a Substack since the likelihood of getting it published is negligible.

Here’s a number that should stop every parent in their tracks: approximately one in four infants now lacks Bifidobacterium colonization during early life. This isn’t some microbial trivia, but the foundation responsible for training the immune system, maintaining gut barrier integrity, producing short-chain fatty acids (SCFAs), and creating the metabolic precursors for one of the brain’s most essential neurotransmitters: acetylcholine.

Sabine Hazan, MD, has been one of the few researchers willing to follow the data where it leads, documenting persistent bifidobacterial collapse after mRNA COVID vaccination. Monica Krueger’s work has demonstrated glyphosate’s targeted destruction of the same bacterial genus. But the question I’m raising here goes deeper: what about the childhood vaccine schedule itself? And what happens when a child is hit with both glyphosate and a bifido-depleting vaccine?

The answer, I hypothesize, (I trace the biochemistry), points at the ADHD epidemic that mainstream medicine hasn’t explained via the root causes.

The Two-Pronged Assault: Glyphosate and Vaccines Converge on the Same Target

Sabine Hazan’s Findings: mRNA Vaccines Deplete Bifidobacteria

Hazan’s work, presented at the American College of Gastroenterology and published in The American Journal of Gastroenterology, demonstrated something no one in the vaccine establishment wanted to see.

In her longitudinal study, subjects receiving mRNA SARS-CoV-2 vaccines (Pfizer or Moderna) showed dramatic drops in Bifidobacterium relative abundance. One month post-vaccination, bifido levels fell to 38%, 49%, 90%, and 258% of pre-vaccine levels across four subjects. But the real shocker came at 6–9 months post-vaccination, where every single subject had dropped below 1% relative abundance with one hitting absolute zero. The numbers: 15%, 0%, 35%, and 60% of pre-vaccine levels.

In her larger cohort of 34 subjects, the median Bifidobacterium relative abundance dropped from 1.13% pre-vaccination to 0.64% post-vaccination (a statistically significant decline [p = 0.0065]). Bifidobacterium was the only genus that showed significant change with vaccination.

This is not a transient blip in the screen. The findings demonstrate an absence of a keystone genus that is a crucial player for children’s health - this study merits further investigation.

Monica Krueger’s Work: Glyphosate’s Gut Microbiome Sabotage

Glyphosate’s mechanism is biochemically well-established: it targets the shikimate pathway, which human cells don’t possess but bacteria do. Bifidobacterium and Lactobacillus species are particularly susceptible because they utilize the glyphosate-sensitive EPSPS enzyme.

What Krueger and subsequent researchers have demonstrated is that glyphosate exposure even at doses considered “safe” by regulatory standards (the U.S. Acceptable Daily Intake or ADI), produces significant depletion of Bifidobacterium and Lactobacillus populations. A key study using the SHIME (Simulator of Human Intestinal Microbial Ecosystem) technology showed that Roundup® and glyphosate exposure to infant gut microbiota caused large-scale microbial disturbances, including acidification of the gut environment that favored pathogenic bacterial growth.

Glyphosate at the U.S. ADI level depleted Bifidobacterium pseudolongum and Lactobacillus species, reduced SCFA biosynthesis pathways, and increased pro-inflammatory markers. The gut dysbiosis was accompanied by elevated fecal pH and the activation of systemic inflammation.

The Convergence: What Happens When Both Hit the Same Child?

This is the ultimate horror scenario as well as my own persistent nightmare. A child exposed to glyphosate through food (don’t forget moms’ diet/breastfeeding), water, and environmental residues (think schools, playgrounds, state parks, and forests) already has a compromised Bifidobacteria population. Then you add a vaccine and the question I’m raising is whether other childhood vaccines beyond the COVID mRNA shots also deplete Bifido?

This is the question I cannot get out of my mind ever since I read Hazan’s study on the Covid vaccine and Bifidobacteria. Where are the studies?

The mechanism by which vaccines could disrupt the gut microbiome isn’t limited to mRNA technology. Immune activation itself, the inflammatory cascade triggered by any vaccine, shifts the gut ecology. The adjuvant-driven Th2 skewing, the systemic inflammatory response, and the potential for molecular mimicry can all alter the microbial terrain. We know that antibiotics decimate Bifidobacteria. We know that intrapartum antibiotics during labor produce persistent B. longum depletion lasting at least one year. The question I raise is whether vaccine-induced immune activation produces similar or synergistic damage?

My hypotheses are untested. Is anyone else thinking about this? Why is there a research gap?

The CDC, NIH, and pharmaceutical manufacturers have shown no interest in studying what the childhood vaccine schedule does to the infant gut microbiome. But the Hazan data on mRNA vaccines tells us the mechanism is real. If one vaccine type can do it, the burden of proof should be on demonstrating that others don’t and not the other way around.

The Acetylcholine Connection: Why Bifido Loss Explodes ADHD Rates

The Biochemistry: Acetate → Acetyl-CoA → Acetylcholine

Here is a proposed mechanistic metabolic chain I hypothesize that connects a missing gut bacterium to a child who can’t sit still, can’t focus, and gets labeled with ADHD:

1. Bifidobacteria ferment dietary fiber into short-chain fatty acids (primarily acetate, along with propionate and butyrate).

2. Acetate crosses the blood-brain barrier and is converted to acetyl-CoA in the brain.

3. Acetyl-CoA is the rate-limiting substrate for the enzyme choline acetyltransferase, which synthesizes acetylcholine.

4. Acetylcholine is the primary neurotransmitter governing attention, memory, learning, and executive function which are the exact areas that are lacking in ADHD.

This is what I’m thinking:

No bifidobacteria → no acetate production → reduced acetyl-CoA → impaired acetylcholine synthesis → attention deficit.

Is this speculative biochemistry? The research demonstrating lower SCFA levels in ADHD patients is now substantial. Before I get skewered, let’s look at published data:

1. A 2022 study of 233 ADHD patients found significantly lower plasma concentrations of formic, acetic, propionic, and succinic acid in adults with ADHD compared to healthy controls. Among children with ADHD, those on stimulant medication had even lower acetic and propionic acid levels and the medication itself appears to further suppress microbial diversity and SCFA production.

2. The 2025 study in Scientific Reports confirmed: ADHD children have lower acetic acid, propionic acid, and butyric acid compared to healthy controls, with the medicated group showing the most pronounced reductions. Propionic acid levels were negatively correlated with ADHD symptom severity; the lower the SCFA, the worse the symptoms.

The Bifidobacterium-Dopamine Axis

A deeper dive. Why look at dopamine?

The connection goes deeper than SCFAs alone. Bifidobacterium species could influence the dopamine system through a sexy pathway: they elevate production of cyclohexadienyl dehydratase (CDT), which increases phenylalanine levels, which in turn drives dopamine synthesis. Dopamine dysregulation could be the core pathology in ADHD in addition to other neurotransmitter dysregulation/factors. This could be why methylphenidate and other amphetamines “work” (they flood the synapse with dopamine). But what if the root cause isn’t a dopamine transporter problem, but a Bifidobacterium deficiency that starves the dopamine pathway of its precursors?

The review published in Nutrients (2019) identified Bifidobacterium as a potential biomarker for ADHD, reporting on its role in dopamine synthesis, SCFA production, and BDNF regulation. Brain-derived neurotrophic factor (BDNF), which is crucial for neurogenesis and neuronal health, is modulated by SCFAs. Germ-free mice show decreased BDNF and impaired working memory. Human ADHD patients consistently show lower BDNF levels.

More on BDNF that can’t be ignored…

The BDNF Evidence: mRNA Vaccines and the Spike Protein Both Hit It

The Erdogan Study: Direct BDNF Suppression by the Vaccine

Erdogan MA, et al. Prenatal Exposure to COVID-19 mRNA Vaccine BNT162b2 Induces Autism-Like Behaviors in Male Neonatal Rats: Insights into WNT and BDNF Signaling Perturbations. Neurochemical Research. 2024.

This is the paper that got the establishment to hit the panic button; it was published, then retracted by Springer Nature, which in the current academic climate tells you exactly how threatening the findings were. Here’s what it found:

• Pregnant rats received the Pfizer mRNA vaccine during gestation.

• Brain BDNF levels were significantly decreased in both male and female offspring (p < 0.001 for both).

• Male offspring exhibited pronounced autism-like behaviors (reduced social interaction, repetitive behaviors, and impaired motor coordination).

• Significant reductions in neuronal counts in critical brain regions.

• WNT signaling pathway disrupted (a pathway essential for neurodevelopment and synaptic function).

• Notably, no significant changes in brain IL-17, TNF-α, or IL-1β, meaning the BDNF suppression wasn’t just a downstream effect of general neuroinflammation. It was a targeted hit.

The fact that this study was retracted despite passing peer review at a Springer journal is in itself significant. The retraction came after publication, not before; this is the kind of post-hoc censorship that’s become standard when findings threaten the narrative.

The Spike Protein Itself Suppresses BDNF

Erdogan MA, et al. Prenatal SARS-CoV-2 Spike Protein Exposure Induces Autism-Like Neurobehavioral Changes in Male Neonatal Rats. Journal of Neuroimmune Pharmacology. 2023.

This is the companion study (same research group) that isolated the mechanism. They injected pregnant rats with purified spike protein plus aluminum hydroxide adjuvant (mimicking the vaccine’s contents without the mRNA).

Results:

• Male offspring showed autism-like behaviors (impaired social interaction, passive avoidance deficits, and repetitive behavior).

• BDNF levels were significantly lower in spike protein-exposed males.

• Gliosis and neuronal cell death in the CA1-CA3 regions of the hippocampus and cerebellum.

• Elevated MDA (oxidative stress marker), TNF-α, IL-17, NF-κB, and lactate; this time the inflammatory markers were elevated, suggesting the isolated spike protein triggers a different inflammatory profile than the full vaccine formulation.

What I surmise is that the mechanism, the spike protein itself, whether produced by the vaccine or via infection is the neurotoxic factor and surpasses BDNF. The vaccine makes your cells produce spike protein. The spike protein crosses the blood-brain barrier and/or triggers peripheral effects that cascade centrally. BDNF drops. Neurodevelopment is vulnerable to these biologic disruptions.

The In Vitro Confirmation

A 2025 study in PubMed (Effects of Exogenous SARS-CoV-2 S1 Protein and mRNA Vaccines on Mixed Neuronal-Glial Cell Cultures) added another layer:

• SARS-CoV-2 S1 protein at 50 µg/mL induced neuronal death in neuronal-glial co-cultures.

• Single vaccine doses didn’t kill neurons outright after 7 days, but three repeated treatments with mRNA vaccines at 6 ng/mL caused microglial proliferation, meaning the cumulative dosing matters.

• Sex-dependent effects: female brain slices showed more microglial activation from the Tozinameran/Riltozinameran vaccine, while male slices were less affected, but the Erdogan data showed males were more vulnerable behaviorally. The sex-specific vulnerability patterns are complex and not fully mapped.

How BDNF Suppression Fits The Bifidobacteria-Acetylcholine-ADHD Model

Two parallel mechanisms by which vaccines can impair neurodevelopment can converge:

Pathway 1: Bifidobacteria Depletion → Reduced SCFAs → Reduced BDNF

As I have laid out in this article, SCFAs (acetate, propionate, and butyrate) modulate BDNF production. Germ-free mice have decreased BDNF. The gut-brain-microbiome axis regulates BDNF through microbial metabolites. When bifidobacteria are wiped out, SCFA production collapses, and BDNF drops as a downstream consequence.

Pathway 2: Spike Protein → Direct BDNF Suppression

The Erdogan studies show the spike protein, whether from the vaccine or infection, suppresses BDNF expression in the brain. This isn’t mediated through the gut. It’s a direct neurotoxic effect.

The Double Hit

A child with glyphosate-depleted Bifidobacteria already has compromised SCFA production and therefore compromised BDNF signaling (Pathway 1). Then you administer a vaccine that produces spike protein, which directly suppresses BDNF (Pathway 2). The child’s brain gets hit from both directions simultaneously impacting the gut which can’t make enough SCFAs to support BDNF, and the spike protein is actively suppressing what little BDNF remains. Perhaps this is how adult-onset ADHD develops as well.

BDNF and ADHD

The BDNF-ADHD connection is well-established:

• Corominas-Roso et al. (2013): Adults with ADHD have significantly lower serum BDNF than healthy controls.

• Akay et al. (2018): Drug-naïve ADHD boys had low BDNF; methylphenidate treatment increased BDNF and improved symptoms. The stimulant is partially compensating for the BDNF deficit.

• Amiri et al. (2010): Same finding: ADHD children have lower BDNF, stimulants increase it.

BDNF is critical for:

• Neurogenesis (birth of new neurons)

• Synaptic plasticity (learning and memory)

• Dopaminergic neuron survival and function

• Prefrontal cortex development (executive function, attention, impulse control)

When BDNF is suppressed during early childhood development, the neurological infrastructure for attention and impulse control doesn’t get built properly. The child doesn’t “outgrow” it because you can’t retroactively build what was never constructed.

A Neurodevelopmental Model

The Unified Mechanism:

1. Glyphosate depletes Bifidobacterium → reduced SCFA production → impaired BDNF expression (gut-brain axis disruption).

2. Vaccine-induced spike protein → direct BDNF suppression in the brain (neurotoxicity).

3. Both hits converge on BDNF deficiency during neurodevelopmental windows.

4. Low BDNF → impaired dopaminergic development, reduced synaptic plasticity, prefrontal cortex dysfunction.

5. Clinical outcome: ADHD, autism-spectrum behaviors, impaired executive function.

And the final gut-punch: methylphenidate increases BDNF. That’s part of why it “works.” We’re using amphetamine-class drugs to artificially elevate a neurotrophic factor that the child’s environment (the food supply and the vaccine schedule) has systematically suppressed. We’re not treating a disease.

Let this sit: We’re medicating an iatrogenic and environmental injury.

The Numbers Don’t Lie

ADHD diagnoses in U.S. children have risen from roughly 6% in the late 1990s to over 11% today and in some populations, much higher. (CHAMACOS: Eskenazi, et al, 1999- ongoing, Salinas Valley, CA: the longest running birth cohort study of pesticide exposures in a farmworker community demonstrating neurodevelopmental deficits in children.) We’re past 6 million children diagnosed. The parallel rise in glyphosate use (which exploded with Roundup Ready crops in 1996) and the expansion of the childhood vaccine schedule (from roughly 10 shots in the 1980s to 72 doses by age 18 in the current CDC schedule) creates an exposure timeline that maps with uncanny precision onto the ADHD curve. (https://alanplewis.com/wp-content/uploads/2024/08/Glyphosate_research_papers_compiled_by_Dr_Alex_Vasquez-1.pdf)

Mainstream medicine calls this correlation. But when you have:

• A known mechanism (Bifidobacteria depletion)

• Two known Bifido-depleting exposures (glyphosate and vaccines)

• A known metabolic consequence (reduced acetate → reduced acetylcholine)

• A known clinical outcome (attention deficit)

...you’re not looking at a coincidence. You’re looking at cause and effect. Where are the synergistic studies to confirm or negate these findings? Note the graph below produced by superimposed government datasets demonstrates the correlation between ADHD and glyphosate researched and published by Seneff and Swanson:

Do Other Vaccines Deplete Bifidobacteria?

This is the glaring research question that remains largely unanswered and the absence of data is itself damning.

What we know:

• Intrapartum antibiotics (given during labor for GBS prophylaxis) produce persistent Bifidobacterium longum depletion lasting at least one year, accompanied by a pro-inflammatory T-helper response in the newborn.

• Neonatal antibiotic exposure is associated with significantly lower antibody responses to pneumococcal and Hib vaccines and the mechanism is Bifidobacteria depletion. A 2025 Nature paper demonstrated that Bifidobacterium species are essential for optimal vaccine responses, and that administering a Bifidobacterium concoction restored vaccine immune responses in germ-free mice.

• mRNA COVID vaccines deplete Bifidobacteria persistently, as Hazan demonstrated.

• The immune activation from any vaccine evidenced by fever, the cytokine release, and the inflammatory cascade shifts gut ecology. Febrile responses alter intestinal permeability. Inflammatory cytokines change the microbial terrain.

The childhood vaccine schedule administers multiple immune stimulating agents simultaneously at well-baby visits; hepatitis B at birth, then the 2-month barrage (DTaP, HIB, IPV, PCV13, rotavirus), repeated at 4 months, 6 months, and on through 15–18 months. Each of these visits triggers systemic immune activation. Each one has the potential to reshape the developing gut microbiome during the vulnerable window when Bifidobacteria colonization is being established.

No one has studied this. No one has taken serial stool samples from infants before and after their scheduled vaccinations to measure what happens to Bifidobacteria populations. The studies don’t exist because no one with funding wants them to exist. The Precautionary Principle states if an intervention might cause harm, the burden of proof of safety falls on those promoting the intervention: this protective armor for children has been inverted. We inject first and ask questions…never.

The Combined Hit: Glyphosate + Vaccine Exposure in the Developing Child

Let’s summarize what could happen to the child who gets both hits:

Prenatal and early-life glyphosate exposure through maternal diet (conventional grains, soy, corn products), water contamination, and environmental residues. The glyphosate has already suppressed Bifidobacterium and Lactobacillus populations before the child’s first birthday. The gut environment is acidified, favoring pathogenic overgrowth. SCFA production is already compromised.

Then the vaccine schedule begins. Hepatitis B at birth. The 2-month combination. The immune system which is now already skewed toward inflammation by gut dysbiosis is hit with multiple antigenic challenges and aluminum adjuvants simultaneously. The inflammatory response further disrupts the fragile microbial ecosystem. Bifidobacteria populations, already suppressed by glyphosate, can’t recover. The metabolic consequences are compounded.

The result: a child with chronically low acetate production, impaired acetylcholine synthesis, disrupted dopamine precursor pathways, reduced BDNF, systemic low-grade inflammation, and a gut-brain axis that’s been sabotaged from both directions.

This child enters toddlerhood with the neurochemical deck stacked against attention, impulse control, and emotional regulation. By age 4 or 5, they’re restless, impulsive, and unable to focus. By age 7, they have an ADHD diagnosis and a prescription for methylphenidate which, ironically, further suppresses SCFA production and microbial diversity, deepening the biochemical hole.

The stimulant “works” in the short term by forcing dopamine into the synapse. But it doesn’t restore Bifidobacteria. It doesn’t produce acetate. It doesn’t fix the root cause. And the child stays on it for years, then decades, while the underlying gut dysbiosis worsens.

What This Means for Our Children’s Health: The Full Clinical Picture

The health consequences of Bifidobacteria depletion extend far beyond ADHD:

Part II in this series examines the restoration pathways and what can be done. Over decades of pediatric practice, I have observed that many children with neurodevelopmental and behavioral challenges exhibit profound microbiome disruption. When the microbiome is restored, clinical improvement often follows. These clinical successes can support my hypotheses and simultaneously raise important questions regarding the environmental factors that create Bifidobacteria depletion and subsequent neurodevelopmental sequelae.

July 21, 2026, 12 noon PST: stay tuned for The New MDS podcast with Dr. Sabine Hazan.