"Why do I have food intolerances?"
Dr. William DavisPublished on April 24, 2026
Summary authored by editor@wellifi.com
TLDR Summary
Food intolerances are on the rise due to an overgrowth of harmful bacteria in the gut, particularly gram-negative proteobacteria. Addressing these imbalances through targeted probiotic use can potentially alleviate symptoms and improve overall gut health.
Key Points
- Food intolerances are increasingly common, affecting nearly a quarter of the population.
- Gut health, particularly an overgrowth of gram-negative proteobacteria, is linked to food intolerances.
- Endotoxemia can lead to serious health issues, including mental health problems and digestive disorders.
- Testing methods for food intolerances include hydrogen breath tests and stool analysis.
- Some probiotics may help restore gut health and alleviate food intolerances.
Understanding Food Intolerances and Their Connection to Gut Health
In recent years, food intolerances have become increasingly prevalent, affecting a significant portion of the population. While our grandparents rarely faced such issues, today nearly a quarter of people report various food sensitivities. This blog post explores the underlying causes of these intolerances, particularly the role of gut health and bacterial overgrowth.
The Rise of Food Intolerances
Food intolerances can manifest in various ways, including reactions to:
- FODMAPs (fermentable oligosaccharides, monosaccharides, disaccharides, and polyols)
- Nightshades (e.g., eggplant, tomatoes)
- Histamine-containing foods (e.g., cheese, wine)
- Fructose
- Gluten and gliadin
The increase in food intolerances is linked to an overgrowth of specific types of bacteria in the gastrointestinal tract, particularly as seen in conditions like small intestinal bacterial overgrowth (SIBO). This phenomenon has connections to liver diseases, with a high prevalence of SIBO found in individuals with liver dysfunction.
The Role of Gram-Negative Bacteria
One of the critical players in food intolerances is a group of bacteria known as gram-negative proteobacteria. These bacteria, which include species like E. coli and Pseudomonas, possess a component in their cell wall called lipopolysaccharide (LPS) or endotoxin. When these bacteria proliferate, they can release endotoxins into the bloodstream, leading to various health issues.
Understanding Endotoxemia
Endotoxemia refers to the presence of endotoxins in the bloodstream, which can lead to severe health consequences, including:
- Sepsis
- Respiratory failure
- Kidney dysfunction
- Disruption of blood pressure
In cases of SIBO, there is a significant rise in endotoxin levels, leading to various symptoms that often accompany food intolerances, such as:
- Abdominal pain
- Diarrhea
- Mental health issues (e.g., depression, anxiety)
- Skin conditions (e.g., eczema, psoriasis)
- Muscle and joint pain
Identifying Food Intolerances
To determine whether food intolerances are present, there are several methods available, including:
- Hydrogen breath testing using devices like the Aire device
- Stool testing to analyze microbial composition
Stool tests can indicate an overabundance of proteobacteria, which may signal dysbiosis and SIBO.
Conventional Treatments vs. Alternative Approaches
Conventional treatments for SIBO typically involve antibiotics like Xifaxan. However, this approach may not be entirely effective for everyone, and the costs can be prohibitive. In contrast, a more natural solution involves the use of specific probiotics that can help restore gut health. For example, strains such as Lactobacillus reuteri, Lactobacillus gasseri, and Bacillus subtilis demonstrate potential efficacy against harmful gram-negative bacteria.
Creating Your Own Probiotic Cultures
One innovative approach to improving gut health is to cultivate specific probiotic strains at home:
- Lactobacillus reuteri and Lactobacillus gasseri can be fermented together at 100°F for 36 hours.
- Bacillus subtilis can be fermented at 90°F for 24 hours.
Consuming these cultures regularly may help alleviate food intolerances and improve overall gut health.
Conclusion
Food intolerances serve as an indicator of underlying gut issues, particularly an overgrowth of harmful bacteria. By addressing these imbalances through targeted probiotic use and dietary modifications, individuals can potentially reclaim their health and reduce the impact of food intolerances on their lives.
For a deeper dive into this topic, consider reading my book, Super Gut, or visiting my website at williamdavismd.com for more resources.