Maybe you feel worn out. Perhaps you’re also having trouble losing weight. Generally, you just don’t feel 100%.

Could it be Hashimoto’s disease? This common autoimmune thyroid disorder is when your immune system (which fights off viruses and bacteria), mistakenly attacks a part of your body. In this case, it’s your thyroid – a gland located at the base of your neck – and can cause low thyroid hormones levels (hypothyroidism).

Hypothyroidism affects one in 33 Australians and Hashimoto’s is one of the most common thyroid conditions in first-world countries.

While symptoms can be subtle, untreated Hashimoto’s can cause long-term problems with your heart, memory and fertility. Here is what you need to know.

What happens when you have Hashimoto’s?

Your thyroid gland is a butterfly-shaped gland in the neck. It is essential in regulating things like muscle function, digestion, metabolism, the heart and lungs. In children, thyroid hormones are also needed for normal growth and development.

Hashimoto’s thyroid disease, named after the Japanese doctor who discovered it in 1912, is also known as Hashimoto’s thyroiditis or chronic lymphocytic thyroiditis. The disease can cause the immune system to mistakenly produce proteins called antibodies (thyroid peroxidase and thyroglobulin). These can cause inflammation and long-term damage to the thyroid gland. Over time, as thyroid tissue is inflamed and/or destroyed, there can be a decrease in the production of thyroid hormones (hypothyroidism).

Hashimoto’s can present subtly at first. If you only have antibodies with no change in thyroid levels, it is likely you won’t have any symptoms.

However, as the disease progresses, you may experience fatigue, weight gain (or difficulty losing weight), increased sensitivity to the cold, constipation, dry skin, muscle aches, irregular or heavy menstrual cycles, enlarged thyroid (goitre) and occasionally hair loss, including at the ends of your eyebrows.

What causes Hashimoto’s thyroid disease?

Several risk factors can contribute to the development of Hashimoto’s including:

• genetic risk – your risk is higher if you have family members with Hashimoto’s

• gender – women are up to ten times more likely than men to develop the disease

• age – you are more likely to develop the disease from 30 to 50 years of age

• autoimmune condition – having another autoimmune condition like systemic lupus, Type 1 diabetes and celiac disease increases your risk

• excessive iodine intake and radiation exposure may also increase risk in people who are already genetically at greater risk.

What are the long-term risks?

Long-term, untreated Hashimoto’s thyroiditis can cause heart issues, higher cholesterol levels, nerve damage (peripheral neuropathy), reduced cognition and infertility.

In pregnancy, Hashimoto’s has a higher risk of pre-eclampsia (high blood pressure affecting several organs), premature birth, placental abruption (when the placenta separates from the inner wall of the uterus before birth) and, in severe cases, pregnancy loss.

The disease has also been linked with an increased risk (but low incidence) of the lymphocytes of the thyroid turning into cancer cells to cause thyroid lymphoma.

How is Hashimoto’s diagnosed?

Diagnosis can be confirmed with a blood test to check thyroid levels and antibodies.

Thyroid peroxidase antibodies are commonly present but about 5% of patients test antibody-negative. In those people, diagnosis depends on the thyroid levels, clinical presentation and ultrasound appearance of general inflammation. An ultrasound may not be required though, especially if the diagnosis is obvious.

Three hormone levels are tested to determine if you have Hashimoto’s.

Thyroid stimulating hormone (TSH) is produced by the brain to speak to the thyroid, telling it to produce two types of thyroid hormones – T3 and T4.

If you have either relative or absolute thyroid hormone deficiency, a test will show the stimulating hormones as high because the brain is trying to get the thyroid to work harder.

Can it be treated?

The management of Hashimoto’s depends on the severity of the thyroid levels. Up to 20% of the population can have antibodies but normal thyroid levels. This is still Hashimoto’s thyroid disease, but it is very mild and does not require treatment. There is no current treatment to reduce antibody levels alone.

Because thyroid peroxidase antibodies increase the risk of abnormal thyroid levels in the future, regular thyroid testing is recommended.

When the thyroid stimulating hormone is high with normal thyroid hormone levels it is termed “subclinical hypothyroidism”. When it is paired with low hormone levels it is called “overt hypothyroidism”. The first is a mild form of the disease and treatment depends on the degree of stimulating hormone elevation.

Overt hypothyroidism warrants treatment. The main form of this is thyroid hormone replacement therapy (levothyroxine) with the dose of the drug adjusted until thyroid levels are within the normal range. This is usually a lifelong treatment but, once the dose is optimised, hormone levels usually remain relatively stable.

In some people with very enlarged thyroid glands causing compressive symptoms (such as difficulty swallowing or breathing), thyroidectomy (surgical removal of the thyroid) is considered.

Hashimoto’s thyroiditis is a common condition caused by your body’s immune system incorrectly damaging to your thyroid and can go undetected. Long-term, untreated, it can cause issues with your heart, cognition, and fertility. It can be diagnosed with a simple blood test. Speak to your doctor if you have any concerns as early diagnosis and treatment can help prevent complications.

Aakansha Zala, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

It has been a long winter, filled with many viruses and cost-of-living pressures, on top of the usual mix of work, study, life admin and caring responsibilities.

Stress is an inevitable part of life. In short bursts, our stress response has evolved as a survival mechanism to help us be more alert in fight or flight situations.

But when stress is chronic, it weakens the immune system and makes us more vulnerable to illnesses such as the common cold, flu and COVID.

Stress makes it harder to fight off viruses

When the immune system starts to break down, a virus that would normally have been under control starts to flourish.

Once you begin to feel sick, the stress response rises, making it harder for the immune system to fight off the disease. You may be sick more often and for longer periods of time, without enough immune cells primed and ready to fight.

In the 1990s, American psychology professor Sheldon Cohen and his colleagues conducted a number of studies where healthy people were exposed to an upper respiratory infection, through drops of virus placed directly into their nose.

These participants were then quarantined in a hotel and monitored closely to determine who became ill.

One of the most important factors predicting who got sick was prolonged psychological stress.

Cortisol suppresses immunity

“Short-term stress” is stress that lasts for a period of minutes to hours, while “chronic stress” persists for several hours per day for weeks or months.

When faced with a perceived threat, psychological or physical, the hypothalamus region of the brain sets off an alarm system. This signals the release of a surge of hormones, including adrenaline and cortisol.

In a typical stress response, cortisol levels quickly increase when stress occurs, and then rapidly drop back to normal once the stress has subsided. In the short term, cortisol suppresses inflammation, to ensure the body has enough energy available to respond to an immediate threat.

But in the longer term, chronic stress can be harmful. A Harvard University study from 2022 showed that people suffering from psychological distress in the lead up to their COVID infection had a greater chance of experiencing long COVID. They classified this distress as depression, probable anxiety, perceived stress, worry about COVID and loneliness.

Those suffering distress had close to a 50% greater risk of long COVID compared to other participants. Cortisol has been shown to be high in the most severe cases of COVID.

Stress causes inflammation

Inflammation is a short-term reaction to an injury or infection. It is responsible for trafficking immune cells in your body so the right cells are present in the right locations at the right times and at the right levels.

The immune cells also store a memory of that threat to respond faster and more effectively the next time.

Initially, circulating immune cells detect and flock to the site of infection. Messenger proteins, known as pro-inflammatory cytokines, are released by immune cells, to signal the danger and recruit help, and our immune system responds to neutralise the threat.

During this response to the infection, if the immune system produces too much of these inflammatory chemicals, it can trigger symptoms such as nasal congestion and runny nose.

What about chronic stress?

Chronic stress causes persistently high cortisol secretion, which remains high even in the absence of an immediate stressor.

The immune system becomes desensitised and unresponsive to this cortisol suppression, increasing low-grade “silent” inflammation and the production of pro-inflammatory cytokines (the messenger proteins).

Immune cells become exhausted and start to malfunction. The body loses the ability to turn down the inflammatory response.

Over time, the immune system changes the way it responds by reprogramming to a “low surveillance mode”. The immune system misses early opportunities to destroy threats, and the process of recovery can take longer.

So how can you manage your stress?

We can actively strengthen our immunity and natural defences by managing our stress levels. Rather than letting stress build up, try to address it early and frequently by:

1) Getting enough sleep

Getting enough sleep reduces cortisol levels and inflammation. During sleep, the immune system releases cytokines, which help fight infections and inflammation.

2) Taking regular exercise

Exercising helps the lymphatic system (which balances bodily fluids as part of the immune system) circulate and allows immune cells to monitor for threats, while sweating flushes toxins. Physical activity also lowers stress hormone levels through the release of positive brain signals.

3) Eating a healthy diet

Ensuring your diet contains enough nutrients – such as the B vitamins, and the full breadth of minerals like magnesium, iron and zinc – during times of stress has a positive impact on overall stress levels. Staying hydrated helps the body to flush out toxins.

4) Socialising and practising meditation or mindfulness

These activities increase endorphins and serotonin, which improve mood and have anti-inflammatory effects. Breathing exercises and meditation stimulate the parasympathetic nervous system, which calms down our stress responses so we can “reset” and reduce cortisol levels.

Sathana Dushyanthen, Academic Specialist & Lecturer in Cancer Sciences & Digital Health| Superstar of STEM| Science Communicator, The University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.