54% of your gut bacteria are vulnerable.
Glyphosate inhibits the EPSPS enzyme in over half of core human gut bacterial species, disrupting their ability to produce essential compounds we depend on for health.
The shikimate pathway powers bacterial nutrition.
This ancient biochemical machinery, completely absent in mammals, accounts for 20-35% of total carbon flux in bacteria. It produces compounds we can only get from our gut bacteria or diet.
Tryptophan
Precursor to serotonin and melatonin—mood and sleep.
Tyrosine
Needed for dopamine and thyroid hormones.
Folate
Gut bacteria synthesize approximately 37% of daily requirements.
Vitamin K2
Essential for bone health and blood clotting.
Beneficial bacteria are more vulnerable.
The sensitivity pattern reveals a concerning asymmetry: minimum inhibitory concentrations for commensal bacteria range from 5-10 mg/mL, while pathogenic bacteria like Salmonella require 20-80 mg/mL for inhibition.
Vulnerable Species
Faecalibacterium (major butyrate producer), Bifidobacterium (immune development), Lactobacillus (gut barrier function and GABA production).
Microbiome Shifts
Studies demonstrate measurable shifts in microbiome composition within two weeks, with significant decreases in beneficial species and increases in potentially harmful bacteria.
Persistent Changes
These compositional changes persist and intensify with continued exposure, with phylogenetic diversity declining significantly over time.
Disruption triggers cascading health effects.
Amino Acid Competition
Bacteria lose their ability to synthesize aromatic amino acids, forcing them to compete for these nutrients from the host diet.
One-Carbon Metabolism
When folate-producing bacteria are inhibited, homocysteine levels can rise—a documented cardiovascular risk factor.
Short-Chain Fatty Acids
Butyrate producers are particularly sensitive, leading to reduced production of these critical metabolites that maintain gut barrier integrity and regulate inflammation.
Scientists debate the risks.
of Americans have detectable glyphosate
of core gut bacteria are intrinsically sensitive
Regulatory Position
EPA maintains current exposure levels are unlikely to cause significant microbiome disruption. EFSA concluded no definitive conclusions can be drawn from microbiome studies.
Independent Research
Peer-reviewed studies demonstrate microbiome effects at or below regulatory limits, suggesting current safety assessments may underestimate risks.
Critical Gap
No studies have directly measured EPSPS pathway activity in human gut bacteria under physiological conditions. Scientists don't know whether dietary amino acids fully compensate for bacterial synthesis disruption.
Human health extends beyond our own cells.
The discovery that a chemical designed to target a pathway “absent in humans” actually affects the majority of our bacterial partners serves as a profound reminder that we depend on a vast microbial ecosystem for survival.