Autoimmune diseases

Specific autoimmune diseases

Autoimmune diseases are a diverse group of conditions in which the immune system attacks a component of our own body. Normally the immune system can distinguish between our own proteins (and other molecular structures) and those of foreign microbes (and substances) but in autoimmune diseases, our own antibodies and immune cells latch onto parts of our body resulting in a cascade of inflammation and destruction. This may lead to the destruction of a particular cell type (e.g. Insulin-producing beta cells or thyroid cells), inflammation mainly limited to one organ (e.g. Rheumatoid arthritis), or damage to multiple organ systems when the immune target is widespread (e.g. Lupus (SLE)).

Genes are our predisposition to autoimmune diseases, but not the cause. Environmental factors have a major role, particularly nutrition. Autoimmune diseases are on the increase. A U.K. database study reported a 22% increase in two decades. Developing nations are now seeing inflammatory bowel diseases that were rare several decades ago.

Autoimmune diseases can be triggered by molecular mimicry – an immune reaction against viruses, bacteria, and other foreign proteins, such as those in food, in which the antibodies produced cross-react with our own proteins. Animal proteins are more likely to resemble our own and to trigger a cross-reaction (e.g. a dairy protein that resembles a protein on (insulin-producing) beta cells). The health of the gut is a key factor in the causation and treatment of autoimmune diseases. 70% of our immune cells are in the gut, many adjacent to the gut barrier, a one-cell thick barrier separating food digestion products and the gut microbiome from our own tissues. Damage to the gut barrier (‘leaky gut syndrome’) and an inflammatory gut microbiome (‘dysbiosis’) can dysregulate immune cells and initiate or perpetuate an autoimmune disease. These mechanisms may explain why people with one autoimmune disease are at greater risk of developing other autoimmune diseases.

Treating autoimmune disease with nutrition and lifestyle:

Pharmaceutical and nutritional treatment is not mutually exclusive. Anti-inflammatory and immunosuppressive drugs can ‘put out the fire’ of active autoimmune disease and stop highly destructive processes. Drugs can be reduced or withdrawn (under medical supervision) when the condition improves or goes into remission. Synthetic hormones like levothyroxine and insulin will need to be continued if tissue damage is permanent. Coeliac disease will require the long-term avoidance of gluten.

‘Food as medicine’ for autoimmune disease includes an anti-inflammatory diet. Effective autoimmune protocols are often plant-based and high in protective foods, such as green leafy vegetables and other vegetables, fruits and spices. Phytonutrients in these foods downregulate inflammation at the cellular level and inhibit inflammatory cytokines such as TNF. Dietary fibre from whole grains, legumes and other whole plant foods fuels the gut microbes that produce short chain fatty acids and other substances that reduce inflammation, regulate immune cells and support a healthy gut barrier. Saturated fats, found mainly in animal products, are inflammatory to the gut and throughout the body. Other components of meat, including the animal protein itself, fuel microbes that damage the gut barrier and cause inflammation throughout the body. Vegetable oil and processed plant products also have a negative impact on gut health and inflammation. Dietary salt (sodium) inhibits beneficial gut microbes and increases the activity of immune cells involved in joint inflammation. A whole foods, plant-based diet ticks all the boxes for promoting a healthy gut microbiome and reducing inflammation.

Treating autoimmune disease with nutrition often requires a high level of adherence. Reduced inflammation may be apparent within days, but the full benefits, sometimes complete remission, can take many months. Not infrequently, the dietary intervention needs to be taken further than low fat, low salt WFPB, with the elimination of gluten-containing grains or other families of plants. Other lifestyle medicine domains are also important: physical activity, quality sleep, resilience to stress and mental health.

Resources

Last updated 23 July 2023