New scientific data is reviving the theory that behind most thyroid disorders lies a virus and an immune system that needs support.
When Amy Meyers was a teenager, she contracted infectious mononucleosis, sometimes referred to as "kissing disease" because the Epstein-Barr virus (EBV) that causes it is transmitted through saliva. Meyers had a fever, swollen glands, joint pains and felt severe fatigue for weeks. It was a pretty bad case of infection, but it recovered - or so she thought at the time.
Now Meyers, who is a doctor in Austin, Texas and author of The Autoimmune Solution (Harper Collins, 2017), is convinced that that period of mononucleosis was not the end of her fight with the virus.She believes that the infection she contracted as a teenager was a major factor in the development of autoimmune thyroid disease later in life, and there is new medical evidence for the theory that Epstein Barr and other viral infections are a major underlying cause of thyroid disease.
Years after the infection, while in her second year of medical school, Meyers was diagnosed with Graves' disease - a condition in which the immune system mistakenly attacks the thyroid gland, which in turn becomes overactive.
Meyers was around 20 when she had trouble sleeping, and she was exhausted day and night. She lost a lot of weight while eating cookies and pizza, and noticed that she always had a mild sweating and palpitations for no apparent reason.She felt very tired and for the first time in her life she had panic attacks. The trembling in her hands, which was observed by others, prompted her to visit a doctor.
As many people with thyroid disease have experienced, Meyers' doctor initially devalued her symptoms. She said it was simply the result of her stress due to medical school. Having already experienced the anxiety of her mother's death from cancer, Meyers was convinced that her symptoms were not just anxiety. She underwent a full examination and was diagnosed with Graves' disease.
Thyroid Epidemic
The American Association of Endocrinologists estimates that 27 million Americans suffer from thyroid disease, about half of them undiagnosed, and the British Thyroid Foundation estimates that one in 20 people in the UK suffers from a disorder.
Women are particularly vulnerable as one in eight women will develop a thyroid disorder during their lifetime. In fact, the thyroid epidemic has been on the rise for decades, and shows no signs of cessation.The thyroid gland, often described as a butterfly, has two lobes on each side of the trachea and is located low in the front of the neck just below Adam's apple. Every cell type in the body has receptors for thyroid hormones.
An overactive thyroid, as in the case of Graves' disease, usually produces symptoms similar to those experienced by Meyers, including weight loss, anxiety, tachycardia and tremors. Another common symptom is sensitive eyes.
A dysfunctional thyroid (hypothyroidism), which produces very few hormones, results in a wide range of symptoms - most commonly slowing heart rate, constipation, fatigue, feeling cold, weight gain, poor concentration and depression. The most common type of hypothyroidism is Hashimoto's disease.
The majority of both thyroid diseases (hyperthyroidism and hypothyroidism) are thought to be the result of a disorder of the immune system - which presents with self-invasion of thyroid components. Depending on which particular thyroid protein is attacked by the overactive immune system, different symptoms appear and different diagnoses and names of autoimmune diseases are given.
Recent studies have shown that many cytokines - small proteins that are important factors in regulating the immune system - are involved in thyroid disorders - fueling inflammation. An overview of the issue in 2015 concludes that these cytokines are critical to the overall picture of thyroid disease, but it has not yet been clarified how they work. But a disorder in the immune system can explain why thyroid disease is often accompanied by other immune system disorders such as vitiligo, juvenile diabetes and celiac disease.
All this adds to an increasingly clear picture that autoimmune thyroid disorder is part of a larger out-of-control inflammatory response that can affect other parts of the body. The thyroid gland suffers because the immune system suffers.
The Role of The Virus
Epstein-Barr virus (EBV), which causes mononucleosis, is one of the ubiquitous herpes viruses that appears to be found everywhere. Once the infection is complete, it does not die or disappear. Remains inactive in the host for the rest of his life, does not reproduce, he is not active, he is just there and can be reactivated years later when there is an opportunity.
When the immune system is strained and depleted, the virus reappears, reproducing itself. It may not be noticeable, but every time this process takes place, the immune system is "activated" and any subsequent activation makes the immune system more likely to fall into autoimmunity in the future. In an autoimmune attack, the overactive immune system attacks the body's own cells, which are genetically similar to parts of an infectious virus.
A 2009 study by Japanese researchers looked at what happens to the mouse's immune system when it is repeatedly stimulated (by immunization) beyond the steady state. They have shown that autoimmunity occurs "as a natural consequence of a normal immune response when stimulated to the maximum.
In the 1970s, EBV infection was linked to autoimmune diseases such as multiple sclerosis and lupus erythematosus. But because most people are infected with the virus (tests show that 96% of the population over the age of 40 have antibodies to the virus) and most people do not develop autoimmunity, the theory has been abandoned. But again in 1997, researchers in Oklahoma published strong evidence that EBV infection was a necessary feature for the development of autoimmune lupus and that the virus was present in almost all patients at levels much higher than in healthy individuals.
Since then, EBV has also been identified as a key feature of other common autoimmune diseases, such as multiple sclerosis, rheumatoid arthritis and autoimmune hepatitis. Patients with thyroid disorders have been diagnosed with higher levels of EBV antibody than normal.
An overview of the 2016 literature on the role of EBV in autoimmune thyroiditis (thyroid inflammation) concluded that the virus "can be considered a contributing factor to the disease", although its exact role is not yet understood. However, other infections such as mycoplasma pneumonia have also been implicated in autoimmune thyroid disease and have not been extensively investigated by conventional medicine.
Reduced Ιmmunity
The question remains why some people have a more controlled reaction to the Epstein-Barr virus (EBV) infection, where the virus remains dormant for a lifetime, while in others it recurs again and again and causes damage to the immune system.
The answer seems to be the ability of each person's immune system to fight EBV, specific genetic weaknesses, nutritional deficiencies and pressures, and the number and frequency of other infections and immunizations that may have triggered the immune system autoimmunity.
Most alternative therapists recommend diets to eliminate foods that may stimulate autoimmune activity, and this usually includes stopping gluten, cereals, and legumes, which are common triggers for autoimmunity. They also advise lifestyle changes to reduce toxins that interfere with immune and thyroid function. However, it is also important to address nutrient deficiencies and to treat the presence of viruses as a step towards treatment by preventing autoimmunity.
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