What Foods Cause GBS? Understanding the Link to Foodborne Illness

January 9, 2026 •

3 min read

Approximately 40% of Guillain-Barré Syndrome (GBS) cases in the United States are preceded by an infection with the bacterium Campylobacter jejuni, which is often found in food. This article explains what foods cause GBS, exploring the link between certain foodborne infections and this rare, serious neurological disorder.

Quick Summary

Guillain-Barré Syndrome (GBS) is often triggered by foodborne infections, especially from Campylobacter jejuni found in undercooked poultry and raw milk, due to molecular mimicry.

Key Points

Primary Cause: GBS is most often triggered by a preceding infection with the bacterium Campylobacter jejuni.
High-Risk Foods: Undercooked poultry and unpasteurized dairy products are major sources of Campylobacter and increase the risk of GBS.
Mechanism: The immune system's attack on the nervous system is caused by 'molecular mimicry,' where antibodies confuse bacterial proteins with nerve cells.
Prevention: Practicing proper food hygiene, like cooking meat thoroughly and avoiding cross-contamination, is key to preventing the triggering infection.
Other Triggers: While less common, other foodborne pathogens like Listeria and Salmonella can also precede GBS.
Contaminated Water: Drinking untreated water is another potential source of the bacterial infections that can lead to GBS.

The Primary Culprit: Campylobacter jejuni

The strongest and most frequent link between a foodborne pathogen and the subsequent development of Guillain-Barré Syndrome is the bacterium Campylobacter jejuni. This common bacterium causes campylobacteriosis, a type of food poisoning with symptoms like diarrhea, abdominal cramps, and fever. While most people recover without complications, a small percentage may later develop GBS.

Undercooked Poultry

The most common source of Campylobacter jejuni infection is raw or undercooked poultry, particularly chicken. The bacteria can live harmlessly in the intestinal tracts of chickens and other birds, but can contaminate the meat during processing. If chicken is not cooked to a safe internal temperature of 165°F (74°C), the bacteria can survive and cause infection.

Unpasteurized Dairy Products

Raw or unpasteurized dairy products, including milk and soft cheeses, can also harbor Campylobacter and other harmful bacteria. Pasteurization is a heating process that kills these pathogens, making dairy products safe for consumption. Consuming raw milk or cheese made from unpasteurized milk significantly increases the risk of infection and potential GBS triggers.

Other Foodborne Triggers

While Campylobacter is the most common trigger, it is not the only foodborne pathogen linked to GBS. Other bacteria that can cause food poisoning have also been associated with the syndrome.

Listeria and Salmonella

Contaminated foods can contain other bacteria like Listeria monocytogenes and Salmonella. For instance, paneer and cheese can be susceptible to contamination with Listeria and Salmonella if not stored properly. Though less frequently linked to GBS than Campylobacter, these pathogens can also trigger an abnormal immune response.

Contaminated Water and Improperly Stored Foods

Beyond specific products like poultry and dairy, contaminated water is a known source of Campylobacter infection. Additionally, improperly stored foods, especially those high in moisture like cooked rice, can allow bacteria like Bacillus cereus to multiply and produce toxins, leading to food poisoning. While this is a common source of food poisoning, it is another potential precursor to an abnormal immune response.

The Mechanism: Molecular Mimicry

So, how does a foodborne infection lead to a neurological disorder? The connection is explained by a process called molecular mimicry.

Immune Response: When the body is infected with Campylobacter or another pathogen, the immune system creates antibodies to attack the foreign bacteria.
Mistaken Identity: Some variants of Campylobacter have surface proteins (lipooligosaccharides) that closely resemble the gangliosides found on human nerve cells.
Cross-Reactivity: The immune system's antibodies, primed to attack the bacteria, mistakenly start attacking the body's own nerves, leading to nerve damage, inflammation, and the symptoms of GBS.

Preventing Foodborne Infections to Reduce GBS Risk

Since the link to GBS is through the initial infection, preventing foodborne illness is the most effective way to reduce the risk.

Cook Thoroughly: Always ensure meat, especially poultry, is cooked to a safe internal temperature of 165°F (74°C).
Avoid Cross-Contamination: Use separate cutting boards and utensils for raw and cooked foods. Wash hands and surfaces thoroughly after handling raw meat.
Choose Pasteurized: Opt for pasteurized milk and dairy products. Avoid any raw dairy items.
Ensure Clean Water: Drink only treated or bottled water, especially when the safety of the local water supply is unknown.

Food Safety Comparison Table


Food Category	Common Pathogens	Risk of GBS Trigger	Prevention Best Practices
Poultry	Campylobacter jejuni, Salmonella	High (especially if undercooked)	Cook thoroughly to 165°F (74°C), prevent cross-contamination.
Raw Dairy	Campylobacter jejuni, Listeria	High	Consume only pasteurized milk and dairy products.
Contaminated Water	Campylobacter jejuni, others	Medium to High	Use treated, boiled, or bottled water; protect well sources.
Shellfish	Campylobacter, Salmonella, others	Medium (if undercooked)	Cook shellfish thoroughly; ensure fresh, safe sourcing.
Stored Rice	Bacillus cereus	Low (link to GBS is less direct)	Refrigerate cooked rice promptly; do not leave at room temp.

Conclusion

While GBS is a rare condition, the strong causal link between certain foodborne infections and its onset is well-documented. The bacterium Campylobacter jejuni, commonly found in undercooked poultry and unpasteurized dairy, is the most frequently identified antecedent. By practicing diligent food safety—including proper cooking temperatures, avoiding cross-contamination, and choosing pasteurized products—individuals can significantly reduce their risk of contracting the infections that may ultimately trigger GBS. Awareness of these food-related risks is a crucial step toward prevention for public health and individuals alike. For more detailed information on GBS and its triggers, the CDC offers comprehensive resources.

Disclaimer: This article is for informational purposes only and is not a substitute for professional medical advice. Always consult a healthcare provider with any questions about a medical condition.

Frequently Asked Questions

No, GBS is not caused by food directly but by an infection contracted through contaminated food or water. The most common bacteria linked to this is Campylobacter jejuni.

Yes, undercooked chicken is a significant risk factor because it is a primary carrier of Campylobacter jejuni, the bacteria most commonly associated with triggering GBS.

Symptoms of GBS typically appear one to three weeks after the initial foodborne infection, such as campylobacteriosis.

Yes, raw or unpasteurized milk can contain harmful bacteria like Campylobacter and Listeria, which can trigger GBS. It is safer to only consume pasteurized dairy products.

Molecular mimicry is the process where the immune system, after fighting a bacterial infection, mistakes similar-looking nerve cell components for the bacteria and begins to attack the nerves.

No, GBS itself is not contagious. It is an autoimmune response that is triggered by a prior infection, which is not spread from person to person.

Improperly stored high-moisture foods like cooked rice can promote bacterial growth, including Bacillus cereus, which can cause food poisoning. While less directly linked than Campylobacter, preventing any foodborne illness is wise.