Glyphosate Exposure: How This Common Herbicide May Affect Your Gut Microbiome and Nervous System

Bianka Rainbow
Mar 12
3 min read

Glyphosate: What You Should Know About This Widely Used Herbicide

Glyphosate is one of the most widely used herbicides in the world. It is applied in large-scale agriculture as well as in residential areas such as lawns, gardens, and public green spaces.

First registered in the United States in 1974 as the primary ingredient in Roundup, glyphosate has since become a component of many commercial weed-control products used globally.

Despite its widespread use, scientific and public concern has increased in recent years regarding the potential impact of glyphosate exposure on human health. Researchers are particularly examining possible links between glyphosate and changes in the gut microbiome, as well as effects on the nervous system.

Glyphosate and Your Gut Microbiome

Glyphosate works by targeting an enzyme called EPSPS within the shikimate pathway. This metabolic pathway is responsible for producing three essential amino acids in plants and microorganisms.

Because this pathway exists in plants, fungi, and bacteria—but not in human cells—glyphosate was originally considered safe for humans. However, scientists now recognize that many bacteria within the human gut microbiome rely on this same pathway.

By analyzing the structure of the EPSPS enzyme, researchers can classify microbial species as either sensitive or resistant to glyphosate. Current estimates suggest that around 80–90% of microbial species fall into one of these categories.

A healthy gut microbiome depends on a balanced diversity of microorganisms. Some bacteria are naturally sensitive to glyphosate, while others are resistant.

When glyphosate exposure occurs frequently, it may:

Suppress glyphosate-sensitive bacteria
Allow resistant bacteria to proliferate
Alter the balance of microbial species in the gut

This imbalance is known as microbial dysbiosis, and it has been associated with numerous health conditions.

Research on Glyphosate Sensitivity in Gut Bacteria

Scientists from the University of Turku in Finland recently developed a bioinformatics tool designed to predict how sensitive different microbes are to glyphosate.

Using this tool, researchers analyzed bacterial species commonly found in the human gut and discovered that approximately 54% of core gut bacterial species may be sensitive to glyphosate.

Docent Marjo Helander explained that this research provides an important framework for understanding how herbicide exposure might influence gut microbiota.

This type of research is significant because disruptions in the gut microbiome have been linked in scientific literature to many chronic health conditions, including metabolic disorders, immune dysregulation, and neurological conditions.

The findings suggest that widespread glyphosate use may have broader ecological and biological impacts than originally assumed.

Glyphosate and the Nervous System

In addition to its potential effects on gut bacteria, several studies have investigated the possible neurological effects of glyphosate.

Research indicates that glyphosate and glyphosate-based herbicides may be capable of crossing the blood-brain barrier, a protective structure that normally shields the brain from harmful substances circulating in the bloodstream.

Some studies suggest that exposure may contribute to disturbances within the nervous system, including both short-term and long-term neurological effects.

Researchers have also observed potential changes in key neurotransmitters, including:

Dopamine
Serotonin

These neurotransmitters play crucial roles in mood regulation, cognitive function, and overall neurological health.

While more research is still needed to fully understand the long-term effects, scientists continue to explore how environmental chemicals like glyphosate may influence brain chemistry and neurological function.

Why This Research Matters

The growing body of research on glyphosate highlights an important shift in how scientists evaluate chemical safety.

Rather than focusing only on direct toxicity to human cells, modern research increasingly considers how substances interact with the human microbiome and other complex biological systems.

Because gut microbes play essential roles in digestion, immunity, metabolism, and neurological signaling, any substance capable of altering microbial balance may have wider health implications.

Understanding these interactions is an important step toward evaluating how environmental exposures may influence long-term human health.