Thyroid disorders are the most common endocrine condition in Australia with up to 12% of the population experiencing thyroid autoimmunity and 5% with subclinical hypothyroidism. Women are 10 times more likely to have an issue with their thyroid and the risk increases with age.


This article is a thyroid “primer” and will briefly discuss:


  • What the thyroid does
  • Symptoms of thyroid disease
  • What the underlying cause may be


Future articles will discuss testing and naturopathic treatment approaches for thyroid conditions.


Anatomy of the thyroid


The thyroid is a butterfly-shaped, endocrine gland located at the front of your neck. It produces and stores thyroid hormones thyroxine (T4) and the active hormone tri-iodothyronine (T3).


What does it do?

Thyroid hormones regulate metabolism and affect the speed at which cells work. Almost every organ and cell has receptors for thyroid hormone which is why an imbalanced thyroid creates a multitude of symptoms in different systems.


Some of the things thyroid hormones help to regulate include:

  • Breathing
  • Heart rate
  • Body temperate
  • Nervous system activity
  • Muscle strength
  • Female menstrual cycle
  • Movement of food through your intestines
  • Weight
  • Cholesterol

A simplified overview of how the thyroid works


The thyroid gland receives its instructions from the “master” of the endocrine system, the pituitary gland located in the base of the brain. The pituitary releases thyroid stimulating hormone (TSH) in response to low circulating levels of T4. TSH acts on the thyroid to produce T4 and T3. More T4 is made than T3 as it has a longer lifespan. T4 is converted to T3 inside many different cells in the body. A protective mechanism to prevent excess stimulation of the thyroid involves the conversion of excess T4 into reverse T3 (rT3). This molecule can occupy thyroid receptors, but it won’t activate them. A bit like putting the wrong key into a lock. It fits, but it won’t open the door.


What can go wrong with the thyroid?

Inherently thyroid problems result when the hormones become unbalanced. You can have either an underactive thyroid (hypothyroid) where things slow down or an overactive thyroid (Hyperthyroid) when everything speeds up.


These conditions exist on a continuum from overt dysfunction to subclinical presentations. Some people can also swing between hypo and hyperthyroid states.


The table below provides a summary of some common thyroid hormonal imbalances.


Primary hypothyroidism Reduce thyroid hormone synthesis with low body temperature. TSH elevated and T3 and T4 low.
Sub-clinical hypothyroidism Underactivity of the thyroid gland, with symptoms of low thyroid but with TSH within standard laboratory reference ranges.
Euthyroid sick syndrome Impaired conversion of T4 to the active T3 resulting in symptoms of low thyroid. This may occur if there is concurrent liver or kidney disease as these are two organs responsible for converting T4 to T3.
Wilsons thyroid syndrome Excessive production of reverse T3 which blocks T3 from accessing the receptors in cells. A trigger for the increased production of T3 is states of high cortisol.
Hashimoto’s thyroiditis An autoimmune condition where immune cells infiltrate the gland causing inflammation and goitre. Diagnosed by testing for thyroid antibodies.
Secondary Hypothyroidism If there is a dysfunction with the pituitary gland, TSH will be decreased, and the gland will mostly be idle. In this case, there is usually nothing wrong with the thyroid gland itself.
Hyperthyroidism/Thyrotoxicosis Overactivity of the thyroid gland. TSH is very low and T4, and T3 levels are high.
Grave’s Disease An autoimmune condition where antibodies affect the TSH receptor on the thyroid gland. This condition is often associated with bulging eyes or exophthalmos.
Thyroid tumours Usually solitary and benign. They can cause changes in the volume of hormones secreted. They are treated with radioiodine or surgery.


Symptoms of thyroid imbalance

Because the thyroid affects almost every cell in the body an underactive or overactive thyroid can produce a wide variety of symptoms and these symptoms will vary among different people. Keep in mind you need to have a number of these symptoms before being concerned about your thyroid!


Hypothyroid symptoms (Underactive)

Physical symptoms

  • Fatigue and low energy
  • Weight gain not explained by diet or a change in exercise
  • Trouble losing weight
  • Cold intolerance – you’re the one wearing a jumper all the time
  • Stiff or tender muscles
  • Constipation
  • Unusual cramping or tingling, prickling sensations


Physical signs

  • Loss of outer third of the eyebrow
  • Slow heart rate when you’re not an elite athlete
  • Goitre
  • Hoarse voice
  • High cholesterol
  • Heavy periods
  • Brittle/dry hair and periods
  • Dry skin
  • Puffy face



  • Difficulty concentrating
  • Brain fog
  • Depression
  • Memory problems
  • Infertility
  • Decreased libido


Hyperthyroid symptoms (Overactive)


Physical Symptoms

  • Unexplained weight loss
  • Goitre
  • Fatigue
  • Muscle weakness
  • Increased appetite
  • Increased heart rate >100bpm at rest
  • Irregular heart rate
  • Palpitations
  • Shortness of breath
  • Intolerance to heat
  • Increased sweating
  • Increased frequency of bowel motions
  • Trembling or shakiness, a fine tremble of hand
  • Thin skin
  • Itching or hives
  • Brittle hair


Physical Signs

  • Menstrual cycles of increasing length and reduced flow
  • Infertility
  • Elevated blood sugar



  • Anxiety
  • Irritability
  • Insomnia


Graves Disease

This autoimmune hyperthyroidism has some specific symptoms involving the eyes

  • Protruding eyeballs
  • Red, inflamed eyes
  • Light sensitivity
  • Blurry or double vision
  • Reduced eye movement


Why do things get out of balance?

To successfully treat thyroid disorders, you need to uncover what is causing the imbalance and correct it.



The thyroid gland has a lot of blood vessels making it susceptible to damage from environmental toxins and heavy metals. These include bromide from flame retardants, pesticides, hydrogenated vegetable oils and the heavy metals lead, mercury and cadmium. Chlorine, fluoride and bromide have a similar structure to iodine can also damage the thyroid in excess.


Nutrient deficiencies

The thyroid requires the amino acid tyrosine, the minerals iodine, selenium, iron, copper and zinc to make hormones. Deficiencies of these nutrients in your diet may impact on your thyroid function. It’s essential to get assessed before supplementing as iodine, iron and selenium can be toxic if taken to excess.


Dietary goitrogens

Dietary goitrogens can interfere with thyroid function if consumed in large amounts. These include cruciferous vegetables (kale, broccoli, Brussel sprouts etc.), soy, quercetin, resveratrol, nitrates (processed meats). Food goitrogens will only usually become an issue if you are consuming high amounts of them, have an existing thyroid condition or are low in iodine. In the case of the cruciferous vegetables, cooking reduces the amount of goitrogens. Think less raw kale in smoothies and more lightly sautéed with lemon juice with your poached egg!

Immune and inflammation

Any autoimmune or inflammatory condition can impact the thyroid. Autoimmune thyroid and coeliac disease often co-exist.


Hormonal changes

Women can experience changes in thyroid function after giving birth – known as postpartum thyroiditis. Changes in thyroid function can also occur in menopause.



Chronic stress states produce high levels of cortisol which inhibits production of TSH and produces an excess of the inactive reverse T3.


The thyroid is a complex gland and plays a role in many processes in the body. Problems with the thyroid gland can make you feel like you’re pushing through mud both physically and mentally. To correct and manage thyroid conditions requires an approach which takes into account a wide variety of factors. Work with an experienced practitioner who can help bring your thyroid into balance.


Need help with your thyroid?

Norelle Hentschel is an experienced naturopath with a clinic in Stones Corner, Brisbane who enjoys supporting her clients to reach their health goals.


Want more articles like this?

Receive a monthly digest of natural health information to help you become “health” sufficient!

PS. Your inbox real estate is precious, and we will never annoy you with sales pitches or share your details with anyone else. One email a month — that’s it.