Causes of autoimmune diseases

    Experts in the field say that this disease occurs when the body’s normal immune defenses break down and instead of attacking pathogens or, in addition, it attacks the body itself.

     Autoimmunity is characterized by four general components:

  • First, there will be an imbalance between effector and regulatory T cells. The first cells are those that have the role of defending the body, helping it to produce an immune response, and the regulatory T cells are those that suppress the immune response.
  • Elimination or defective control of auto-reactive immune cells, which are able to attack the body.
  • A chronic alert immune system.
  • Generalized inflammation.

     To date, specialists have found over 80 different autoimmune diseases. Some are well known, such as type 1 diabetes and multiple sclerosis, while others are rare and difficult to diagnose. It should be noted that this type of disease disproportionately affects women. 

     This phenomenon may be related to the suppressive effect of testosterone, which is much higher in men, or to the production of B cells, immune cells that can become auto-reactive and can trigger an autoimmune reaction.

    People need to know that these diseases arise from a combination of genetic and environmental factors. However, genetics account for only about 25% of the risk of developing an autoimmune disease, while the remaining 75% are related to the environment or with environmental factors or with what we understand as epigenetics.

     I believe that few people realize that the gut is the basis of our health and 80% of the immune system lives there, the health of both is therefore closely linked. In that place, there is the greatest interaction with the outside world, taking nutrients from food and keeping “out” bacteria, pathogens and undigested food.

     If your gut loses its ability to discriminate what is necessary or good and what is problematic or bad, when we talk about “leaky gut” or leaky gut, a leaky gut that allows the passage of all types of molecules in the blood or inside our body, which otherwise or with a healthy intestinal barrier would not occur.

     Researchers who have done such tests say that the intestine is naturally permeable to very small molecules to absorb nutrients from food. In fact, the regulation of intestinal permeability is one of the basic functions of the cells that cover the intestinal wall. If you eat a diet that is poor, full of drugs, toxins, infections and stress, then you may suffer from breaking these tight junctions, and when this happens you increase the risk of autoimmunity.

     In terms of genetics, specific variations in genes, or what is meant by polymorphisms, establish a favorable scenario for autoimmunity by changing the regulation of immune cells. Environmental factors interact with these genes, being decisive in the possible occurrence or not of autoimmune disease, hence the very important 75% of the causes they contain.

     Regarding the mentioned polymorphisms, we are talking for example about the human leukocyte antigen (HLA). The HLA system plays a crucial role in the presentation of antigens (toxins or other foreign substances) to the immune system, and therefore polymorphisms in HLA genes can affect the immune response against antigens. HLA-DQ2 and HLA-DQ8 are well known for their role in celiac disease, HLA-DRB1 is associated with rheumatoid arthritis, and HLA-B27 with spondyloarthritis. Variations in cytokine genes can also increase the risk of autoimmune diseases by producing excessive amounts of pro-inflammatory molecules.

     In conclusion, even if the genes mentioned in this article increase the risk of autoimmunity, they do not guarantee that it will occur. Environmental factors, as we have pointed out, are the ones that really favor or most likely trigger the autoimmune cascade.