Did you know your thyroid gland can cause fatigue if it’s under active, and fatigue and anxiety if it over active? Regularly I see patients more often with sub clinical hypothyroidism, where the thyroid is functioning sub optimally.  If the TSH, or ‘thyroid stimulating hormone’ in your blood, tests between 2 and 5, (this number starts at 0 and can reach over 100), Doctors will tell you it’s okay. Your TSH levels should ideally be between 1 and 2. Commonly TSH is tested in isolation, but always should be tested alongside Free T3 and Free T4 (more about these hormones later). Your thyroid can be under active for years before it shows in blood tests and eventually becomes a full blown thyroid disease.

Your thyroid can be slightly underactive and still produce concerning symptoms for you. Have you been suspecting it’s your thyroid when all you get from your Doctor is – ‘its fine’ ? TSH is a hormone produced by the pituitary gland (in the brain) as a response to thyroid hormones. If your thyroid hormones are too low, then the pituitary will respond by producing more TSH which will stimulate the thyroid to try and produce more thyroid hormones.

What does your thyroid gland actually do?

The thyroid glands hormones regulate oxygen use and basal metabolic rate (BMR), cellular metabolism, growth and development. The thyroid regulates the metabolism by stimulating protein synthesis and the use of glucose for energy. Its hormones play an important role in the maintenance of normal body temperature and accelerate body growth especially the growth of nervous tissue. They also increase triglyceride (a type of fat) breakdown and excretion of cholesterol. (1). Commonly, people with high cholesterol have thyroid issues.

If hormone levels drops below normal, metabolism inside your cells slows down and energy levels drop. If the hormones become too high, the metabolism and all the body processes speed up. The thyroid also affects the body’s sensitivity to adrenal hormones.

“both the glands produce hormones that regulate our energy levels. In a simplified sense, the thyroid gland sets our “idle” level or our baseline energy level, and the adrenal glands acts as the accelerator for our energy level when demand is higher”

Dr. Banks, Endocrine specialist, USA

For more information on the adrenal glands please see my blog ‘3 stages of adrenal dysfunction and what to do about it’.

 The main Thyroid hormones

 TSH is thyroid stimulating hormone, which is produced by the Pituitary gland in the brain. TSH acts on the thyroid gland which produces the thyroid hormones T3 and T4, using the nutrients tyrosine and iodine.

TBG is thyroid binding globulin which carries T4 and T3 to the tissues to exert their metabolic effect.

T4 is thyroxine (contains 4 molecules of iodine), the ‘inactive’ thyroid hormone which is the precursor to T3 or reverse T3

T3 is Triiodothyronine (contains 3 molecules of iodine), the ‘active’ hormone is produced when the body needs energy, by removing  an iodine atom From T4, it then becomes  T3. T3 is 5 to 7 times more biologically active than T4.

RT3 is reverse T3, an inactive form of T3, which is made by the body to tone down energy. If reverse T3 is too high it binds up your ‘active’ Free T3, which can cause symptoms of hypothyroidism despite a normal thyroid function test.

TRH is thyrotropin releasing hormone which is released by the hypothalamus gland in the brain. It monitors the levels of thyroid hormones in the body and acts on the pituitary gland to produce TSH.

Thyroid diagram

Brain… thyroid …action !

The hypothalamus (part of the brain that regulates the autonomic nervous system and endocrine glands) monitors the thyroid hormones and produces TRH, which then acts on the pituitary gland (also in the brain) to produce TSH. TSH acts on the thyroid gland to produce T3 and T4. Nutrients used during this process are iodine and tyrosine. T4 is then converted to T3 by deiodinase enzymes, which depend on adequate selenium in the body. This happens mainly in the liver but also in the gut, muscles, brain and the thyroid gland. TBG carries T4 and T3 into the tissues where they become free T3 and Free T4, then binding to thyroid hormones receptors (THR’s ) and exert their metabolic effect.


Common symptoms of an underactive thyroid

The symptoms are very important, the most common being fatigue, poor concentration, feeling mentally groggy, weight gain, dry skin, cold hands and feet, constipation, depression, high cholesterol, high estrogens, heavy periods, hair loss, high blood pressure, fibromyalgia and insomnia. Some people experience a tight feeling around the throat or have frequent throat or lost voice issues. Their reflexes can be slow and they can feel cold all the time or have an intolerance to cold. Some people also get pain or joint stiffness and numbness / tingling in hands and feet including Carpel tunnel syndrome.

Children with hypothyroidism have symptoms that are not as specific as adults, but mainly are fatigue, brain fog and hair loss.

When testing for hypothyroidism it is best to use the basal body temperature test and also look at the blood test results.

How to do ‘The basal body temperature test.’

Take your temperature on waking each morning for at least 5 days. Lying very still in bed for around 10 minutes with a thermometer under your arm. If its digital don’t turn it on until the 10 minutes is up. If its mercury then shake it down the night before. The reading shouldn’t be below 36.4 degrees Celsius. If it is consistently then your thyroid is underactive.

If the temperature is consistently low I usually suggest my patients have a blood test to check TSH, Free T3, Free T4 and reverse T3. A more comprehensive test may involve the thyroid auto antibodies, urinary iodine, homocysteine (an amino acid produced in the body from methionine, another amino acid), serum selenium and plasma zinc.

The overactive thyroid or underactive thyroid…. or both??

I have had an under active and over active thyroid gland at the same time, during a period of high stress in my life. I went from having a racing heart and anxiety to feeling depressed and flat as a tack. Fortunately naturopathy offers effective support for thyroid disorders. It was resolved very quickly with all the right lifestyle changes and the right remedies.

If the thyroid is inflamed or if the immune system decides to attack it, it becomes a form of thyroiditis. A common form is Hashimoto’ disease, where the body produces antibodies against the thyroid tissue. A common trigger is stress and leaky gut, or an existing auto immune disease such as celiac disease. The thyroid becomes inflamed and over produces hormones then eventually becomes under active. Grave’s disease is another auto immune thyroid disease which causes the thyroid to produce too many thyroid hormones.

Hashimoto’s thyroiditis

According to research, 95% of hypothyroid cases are due to Hashimoto’s Disease, an autoimmune thyroid condition. The immune system attacks the thyroid gland and eventually the thyroid loses the ability to produce hormones and hypothyroidism develops. This can take years and in some cases the thyroid can be overactive for a short period of time, but doesn’t last long as it soon becomes underactive. Hashimoto’s is diagnosed by a high level of TSH, low T3 and T4 and the presence of antibodies. The two main anti bodies are TPO (thyroid peroxidase antibodies) and TGAb (Thyroglobulin antibodies). Hashimoto’s is often associated with gluten intolerance and/or celiac disease, so a gluten anti body blood test is also warranted. Vitamin D levels may also be low.

Grave’s disease

This is the most common form of overactive thyroid and accounts for 85% of all hyperthyroidism cases. (4)

Grave’s disease is an autoimmune disease. The immune system produces an antibody that attacks or stimulates the thyroid gland to produce high levels of thyroid hormones. This toxic level of thyroid hormones is called thyrotoxicosis. These people can have symptoms which include extreme anxiety, protruding eyes and cardiac issues. Blood tests involved in diagnosing this disease are Low TSH, High levels of Free T3 and free T4 and thyroid stimulating auto antibodies (TSI). TPO antibodies may also be present.

 Overactive thyroid symptoms.

If the thyroid hormone levels are too high, some of the following symptoms may be present.

Hair loss


Nervousness, shortness of breath

Bulging eyes (in Grave’s disease)

Rapid heart beat

Diarrhoea/ loose stools

Weight loss

Being over sensitive to heat.

Hand tremors

Sometimes a goitre is present (see below),


Increased appetite and increased sweating.

Poor concentration

Light or absent menstruation/periods

Goitre and Thyroid nodules

A goitre is an enlarged thyroid gland and is a symptom of many thyroid disorders. Commonly it is because of inadequate iodine intake which causes low levels of thyroid hormones and the stimulation of TSH can cause enlargement of the gland. Nodules can be part of a multi nodular goitre.

There are many types of thyroid nodules and they are more common in women and in people with iodine and selenium deficiencies. They can also be caused by inflammation of the thyroid gland (as in Hashimotos), radiation or chemical exposure. The four types of single nodules are fluid filled cysts, benign adenoma, slow growing adenoma and rarely a cancerous adenoma. Most nodules are symptomless, but some such as the ‘hot nodules’ which produce thyroid hormones cause the symptoms of hyperthyroidism. Some cysts can also cause neck symptoms such as trouble swallowing and change in your voice.

What affects the thyroid gland?

  • BPA; Bisphenol A, the main source is from plastics but also receipts
  • Chemicals such as organo chlorides (in herbicides and pesticides), PCB’s and PBDE’s , (polychlorinated bisphehyl and polybrominated diphenyl ethers in plastics, adhesives, insulating materials, flame retardants, carpets and upholstery)
  • Chlorine and fluoride in drinking water and fluoride also in toothpaste
  • Goitrogen foods such as unfermented soy products and uncooked cruciferous vegetables
  • Antidepressants
  • HRT or the contraceptive pill, estrogen being the main offender here
  • Heavy metals such as mercury from dental fillings, lead from car fumes and water pipes, and cadmium from car fumes, pesticides and in white flour products.
  • Stress and extreme emotions.
  • The thyroid can be effected if there are problems with expressing oneself

Thyroid function is easily impaired by chronic stress and adrenal fatigue as well as iodine deficiency (which is common in Australia), a high intake of goitrogenic foods, radiation, exposure to toxins and autoimmune thyroid disease. (2)

The thyroid and cardiovascular system.

People with Low T4 / thyroxine levels have slower methylation ability as it slows down MTHFR. MTHFR is an enzyme which breaks down folate into its biologically active form. This leads to an increase in homocysteine, a part of the methylation cycle which if high long term, can cause cardiovascular problems.

Methylation is a metabolic process which happens in every cell of our body and more than a billion times per second. It affects our body’s ability to produce and regulate chemicals, hormones and to switch genes on and off. It is involved in production of neurotransmitters and DNA repair and detoxification.

Thyroid solutions

Your symptoms and type of thyroid disorder, whether full blown or subclinical, are treated individually. Having the guidance of a naturopath is very important whether you are already being treated by a medical doctor or not.

Part of the support is not just for symptoms but for the reasons behind the type of thyroid disorder. Treating and improving gut function is very important for all thyroid disorders. Leaky gut is commonly associated with Grave’s disease and Hashimoto’s, so this needs to be quickly addressed. Nutrient deficiencies also need to be addressed.

Food sensitivities and allergies need to be tested and eliminated. A Gluten free diet is very important to follow in autoimmune disease. Dairy free is also recommended as the casein (milk protein) can produce inflammation and/or immune system problems for many people.

Stress needs to be reduced or avoided, and this includes toxins/ chemical exposure, avoidance of known allergens, overwork and lack of sleep. It is very important to always support the adrenal gland function, at some stage the liver support and even a detox may be needed. .

There are many herbs and nutrients which can help normalise the thyroid and can stand alone or support any medical treatment.

If you suspect thyroid dysfunction, start with your basal body temperature test and then have blood tests. It is important to catch it early to avoid harmful bodily effects it can exert.

I have helped many patients with thyroid disorders over the last 17 years. If you would like my guidance, please book for a consultation. for those of you not in South Australia, I also offer phone or Skype consultations! 

  • References
  1. Principles of anatomy and physiology. Tortora and Grabowski. Thyroid gland, p 520-525
  2. Biopractica Thyroid webinar notes
  3. The importance of Adrenal and Thyroid health – Eagle Professional natural medicine
  4. Your thyroid problems solved – Dr. Sandra Cabot.


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