Have you ever stopped to wonder how you developed Hashimoto’s disease?

These days we tend to blame everything on genetics as if our health is written in stone before we are born. The truth is that the majority of our genes are not expressed and most are not fixed. Under certain conditions they can be switched on or off. Have you heard the phrase, ‘your genetics load the gun but your environment pulls the trigger’? This is very true of Hashimoto’s.

There is a lot that medicine does not know about Hashimoto’s and autoimmunity in general, including the precise cause. It’s widely understood that autoimmune disease seems to be triggered by a matrix of factors that work on our genes, we call this called epigenetics. 

As you will learn there are a number of other factors that are often, but not always, common in the health or social history of those with a Hashimoto’s diagnosis. In my experience speaking with clients with Hashimoto’s they are also not widely known. Let’s take a look at the most obvious factors first then dive into some of the less well known causes.

Hormones

9/10 people with a Hashimoto’s diagnosis will be women. Our periods of hormone fluctuations such as pregnancy, childbirth, perimenopause and menopause leave us at greater risk of developing the condition. It’s extremely common for symptoms to develop postpartum or in perimenopause. Many postpartum thyroiditis cases do resolve but about 50% will develop Hashimoto’s/Hypothyroidism within 5 years. Breastfeeding mothers can be nutrient depleted and under supported which may also play a part. Oestrogen plays an important role in T4 production so when it fluctuates in perimenopause this can be problematic. However, when it is too high it can bind to T4 and prevent conversion to T3, not good! Unfortunately many women struggle with high oestrogen these days. 

The other theory as to why women are more susceptible is our greater exposure to toxins through cleaning, personal care and cosmetic products. There are many endocrine disrupting chemicals used very widely in personal care products that affect thyroid function.

Genetics

Do you have relatives with Hashimoto’s or Hypothyroidism? It’s not a prerequisite for developing the disease but you’re at higher risk if it runs in the family. So let’s educate our daughters and the next generation on prevention so they can give themselves a better chance for avoiding a diagnosis and having a healthy future.

For your interest HLA-DR3, HLA-DR5 and FOXE are the genes associated with Hashimoto’s disease. But again, these genes can be unexpressed or ‘switched off’.

Toxic Exposure

The thyroid is very sensitive to toxins, it is a highly vascular organ that acts like a sponge. While it is trying to capture iodine and other minerals to do its job, sometimes it will capture other similar compounds like chlorine, fluoride and bromine instead. These compounds take up iodine receptor sites, blocking iodine intake and causing inflammation. Swim athletes and swim instructors are therefore at high risk due to their regular exposure to chlorinated pools but these compounds can be an issue in our drinking water too. Fluoride suppresses T4 production, is known as an antithyroid and as a result was used in the past as a hyperthyroid treatment. So depending on what your water supply is like, your tap water may also predispose you to hypothyroidism due to its fluoride and chlorine content.

Other high toxin exposure industries include hairdressing, metalworking and farming. If your parents or grandparents worked in these industries then you may be affected epigenetically. 

Too much iodine is also one of the most well known risk factors. Radiated iodine treatment, iodine based medical contrast dye and inappropriate supplementation can put you at risk of Hashimoto’s or increase your antibodies.

Some other toxin exposures that can put us at risk of thyroid disease are smoking or second hand smoke exposure, pesticides, mycotoxins (mould exposure) and endocrine disruptors like plastics, perfumes etc There is a very long list and I’ll cover it more closely in a blog soon. When we think of endocrine disrupters we think of our reproductive hormones like oestrogen but the endocrine system encompasses thyroid hormones too. The way we live and interact with our environment in our modern lives exposes us to a frightening amount of these each day but there is a lot you can do to minimise exposure.

Dietary Factors

Many nutrients are crucial to the optimal functioning of the thyroid. A few deficiencies have been associated with Hashimoto’s and hypothyroidism including magnesium, iodine, selenium, vitamin D and iron. The thyroid requires four Iodine atoms to synthesise a T4 molecule for example, and adequate stores of many of the nutrients above are required for T4 to T3 conversion so it can get into the cells where it takes action. This is how goitres can form, the thyroid tissue enlarges to try and capture more iodine so it can perform its function. Selenium deficiency in particular has been associated with the development of Hashimoto’s disease. 

Trauma

A surprising association that has been made between autoimmunity and childhood traumatic stress or PTSD. Chronic stress in childhood leads to chronic inflammation and immune dysregulation that can progress into the development of autoimmune disease in adulthood. It makes sense doesn’t it?

I’ve also had many clients who experienced grief and chronic stress in their adult life due to the death of a loved one, a serious physical injury or life-upending events such a divorce suddenly develop symptoms. Whether these stressful periods exacerbate an already brewing condition or trigger them is unknown. 

Stress plays a large role in the development of thyroid dysregulation due to the HPT axis (Hypothalamus/Pituitary/Thyroid connection). This is why many already diagnosed with Hashimoto’s notice their symptoms worsen during periods of stress.

Gut Dysfunction

The gut is where much immune system dysregulation stems from. A poorly functioning gut lining will allow antigens to access the bloodstream and in appropriately interact with immune cells, 80% of which reside behind the lining of the gut. Over time this causes the immune system to become hypersensitive and disordered, responding to harmless substances with antibody production. An imbalance of the bacteria in your gut, called microbiome dysbiosis is often the major driver but excess alcohol, some medications (particularly regular NSAID use), stress, lack of sleep, a diet rich in processed foods and poor glycemic control are all obstacles to a well functioning gut lining. There is a lot that can be said here but essentially a disordered gastrointestinal terrain and function is always part of the picture of autoimmune development.

Infections

Various gastrointestinal and viral infections have been associated with the development of Hashimoto’s disease. Gut bacterial infections such as Helicobactor Pylori and viral infection such as Hepatitis, the Herpes viruses – yes, including the humble cold sore – and notably Epstein-Barr (Glandular fever or EBV) are understood to be triggers for some. Viral infections form part of the human virome. Similar to the microbiome which pertains to the bacteria that live in and on us, viruses can also reside dormant within us until a period of physical or emotional stress can weaken our immune system and reactivate the infection. Unfortunately the thyroid can house these dormant viruses, the theory being that they are causing low grade inflammation in the organ and therefore triggering an autoimmune response. A serious bout of Glandular Fever very often forms part of the health history of a Hashimoto’s sufferer.

So as you can see the cause of Hashimoto’s is about as simple as a PhD in rocket science. It is unique to each person but will always have at least two or three of the factors above. I can personally put my finger on about a dozen of the factors above and see how they played a role in my own autoimmune journey.

I recommend you work out your own triggers and drivers. It is a valuable exercise as it can illuminate areas that you may need to work on in order to regain your health and feel better. I know it has helped me to address those driving factors and improve my thyroid health and autoimmunity over the years. Stress management, therapy, correcting microbiome dysbiosis, anti-viral supplements and foods, correcting deficiencies, blood sugar regulating meals and a simple water filter have all made a difference.