Understanding the Causes behind Autoimmune Diseases

1. Introduction

Autoimmune diseases involve a broad range of conditions in which the immune system malfunctions and mistakenly attacks healthy cells and tissues, leading to chronic inflammation, tissue damage, and organ malfunction. More than 100 different autoimmune diseases attack virtually any part of the body, from the skin and joints to inner organs, tissues, and cells. Even the brain can be affected by autoimmune diseases, such as encephalitis, which can cause headaches, fever, and confusion, among many other symptoms.

At the heart of all autoimmune diseases is the malfunction of the body’s immune system, but the causes behind this malfunction are not fully understood. However, scientists now know there are three major factors behind autoimmune diseases: a person’s genome, a person’s sex identity and their surrounding environment.

People born with specific genetic mutations are more likely to develop certain autoimmune diseases. In most cases, it is not a single gene but a combination of many different genes and other parts of the genome linked with an increased risk of developing an autoimmune disease¹.

Sex is another crucial factor, with women being up to three times more likely to develop certain autoimmune diseases compared to men. Scientists think that some potential factors driving this bias may involve sex hormones, specific genes found in sex chromosomes, or physiological changes that occur in the woman’s body during pregnancy.

But, while genetics and sex play a significant role, recent studies suggest that a person’s environment represents the most critical driver behind autoimmune diseases. Environmental factors, also known as the exposome, are thought to explain up to 70% of all autoimmune diseases. Anything from viral infections and exposure to toxins to dietary habits and alterations to the optimal balance of the gut microbiota has been linked to multiple autoimmune diseases.

2. Focus on the exposome: a significant cause of Autoimmune Diseases.

The exposome is a term used to describe anything found in our environment that can enter our bodies and affect our health. It can involve anything from pathogens, such as viruses and bacteria, to toxins in the air and drinking water or pathologies within our physiology³. The exposome can also refer to the food we eat, how much physical activity we do, or to social factors, such as stress, which can also affect our health⁴.

Within the context of autoimmune diseases, some of the most critical factors of the exposome are discussed below.

Environmental exposures—Our body is exposed to countless chemical and biological factors found in our surroundings. Some of the most common environmental exposures that have been linked to autoimmune diseases include toxic chemicals, biotoxins, and infections. Autoimmune diseases like systemic lupus erythematosus, autoimmune hepatitis, rheumatoid arthritis, and systemic sclerosis have been associated with such environmental factors.

Among these environmental factors, the most substantial scientific evidence linking environmental exposure to autoimmune diseases involves exposure to chemicals found in pesticides, certain industrial solvents, silica, and tobacco cigarette smoking^5-6. Mercury exposure (in some dental amalgams, polluted air and seafood) has also been linked to autoimmunity⁴. More recently, infection with the COVID-19 virus has also been linked to the development of autoimmune disease¹¹.

Intestinal Permeability—Commonly known as “Leaky Gut,” this pathology involves the malfunction of the cells lining the small intestine, which allow pathogens and toxins to pass into the bloodstream and our body. Under normal circumstances, these cells are a barrier to invading pathogens or chemicals. People suffering from systemic lupus erythematosus are commonly diagnosed with intestinal permeability, suggesting a link between these conditions⁷.

Immune malfunction—While many factors are thought to influence the development of autoimmune diseases, in some cases, the issue involves the immune system itself. A recent study, for example, found that immune aging is a risk factor for developing autoimmune disease⁸. As we age, our immune system becomes less efficient at fighting off infections and other environmental exposures, and essential cellular pathways and processes start to malfunction.

Gut Microbiota Pathology—Malfunction of the gut microbiota is associated with a wide range of pathologies, including autoimmune disease⁹. Research studies now show that alterations to the optimal function of the gut microbiota are linked to autoimmune diseases like systemic lupus erythematosus, multiple sclerosis, rheumatoid arthritis, systemic sclerosis, inflammatory bowel disease, and ulcerative colitis⁶.

Diet – The food and beverages we eat represent essential factors influencing our health. Food colouring additives, for example, have been linked to the development of autoimmune diseases. These chemicals can enter the body through the gastrointestinal tract by ingesting food or certain medications laced with these additives10.

More broadly, certain foods are well-known allergens, causing immune reactivity in the body, which can lead to the development of autoimmune disease. Some commonly reactive foods include bread and other products containing gluten, a protein that triggers immune reactions in many people. Likewise, lactose in cow’s milk and cow’s milk-based products can cause immune reactivity. More broadly, following a “Western diet” characterised” d by high-fat and cholesterol, high-protein, high-sugar, and excess salt is associated with a myriad of pathologies that can lead to autoimmune disease¹².

Exercise—Regular exercise has multiple health benefits, such as improving circulation, aiding with optimal tissue repair, and boosting the production of anti-inflammatory chemicals in the body13-14. Research shows that moderate to high-intensity exercise can lead to enhanced immune function, which can help fight off pathogens more effectively and regulate inflammatory reactions, potentially safeguarding you from autoimmune disease^15-16.

Stress occurs when we feel emotional or mental strain due to adverse circumstances. Chronic stress is a well-known factor influencing immune function, partly through the effect of stress-related hormones, such as norepinephrine and glucocorticoids. But there is also a clear association with autoimmune disease. One study, for example, found that people exposed to chronic stress had an increased risk of developing an autoimmune disease¹⁷.

3. What Happens Next? Understanding the Functional Medicine Approach to autoimmune diseases

Autoimmune diseases are difficult to diagnose by a regular GP using a conventional medicine approach. This is because autoimmune conditions have multiple and sometimes non-specific symptoms, which can lead to misdiagnoses.

At AUSCFM, our doctors take a comprehensive approach to assessing your health and immune system, facilitating the identification of mechanisms contributing to immune dysregulation. Initially, our team reviews your health and medical history through detailed questionnaires. Advanced diagnostic tests are advised to uncover disease-related mechanisms in cases of suspected autoimmune disease. Following identification, a customised treatment plan is formulated, incorporating dietary guidance, lifestyle adjustments, exercise recommendations, and advanced formulations to bolster your immune system. The plan also encompasses strategies to enhance nutritional well-being, incorporating stress reduction techniques.

References

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