Thyroid disorders are becoming an increasingly common health concern today, especially among women. In 2014, as per an article on Medscape, levothyroxine (Synthroid) was the most prescribed drug in the USA and the third most prescribed drug in the UK (Davenport, 2016).   In my naturopathic family practice, I see many that have a diagnosed thyroid disorder but also many who have suboptimal levels of thyroid hormones that can explain their symptoms even though they haven’t received a formal diagnosis from their medical doctor as their levels on their blood test are within ‘normal reference ranges’.

thyroid gland
(6) From the National Cancer Institute from the National Institute of Health.

The most common thyroid imbalance is hypothyroidism when your thyroid hormones and/or thyroid function is low resulting in decreased metabolic activity which may contribute to weight gain.  Hypothyroidism can be PRIMARY (originating at the thyroid gland where your T4 and T3 thyroid hormones are low and TSH is elevated) which is the most common form; SECONDARY which originates at the level of the pituitary where TSH is low; or, TERTIARY which originates at the hypothalamus where TRH is low). 

Hyperthyroidism is not as common but this is where you have excess thyroid hormone production. Similar to hypothyroidism, you also have primary/secondary/tertiary hyperthyroidism except for this time that particular tissue is producing an excess of its respective hormone (see above for which organ is affected at each level). The most common cause of primary hyperthyroidism is Grave’s Disease, an autoimmune disorder.


Symptoms of abnormal thyroid hormones

If you have any of the symptoms listed in the box above but your doctor tests your TSH levels only and says your thyroid is fine, I recommend you seek another opinion or at the very least, speak to your family doctor about these key blood tests:

  • Free T4
  • Free T3 (active thyroid hormone that regulates metabolism)
  • TSH (The reference range is quite large but I review optimal ranges which should be somewhere between 1-2.5 mIU/L)
  • Anti TPO antibodies (thyroid peroxidase)
  • Anti TG antibodies (thyroglobulin)
  • TSH receptor antibodies (if thyroid hormones are elevated)
  • rT3

If you have been diagnosed with hypothyroidism, the most common drug he or she will prescribe is Synthroid (levothyroxine) – this is only T4.  The problem with this is that your body still has to convert it into T3 and if your conversion mechanism is impaired, many will still not feel at their best.  Cytomel (liothyronine) is T3 which is another medication that may be prescribed.  Desiccated thyroid (Armour) comes from a porcine source and contains both T3 and T4 however, many MDs are reluctant to prescribe this form.

If you are diagnosed with hyperthyroidism, the medication most often prescribed is tapazole (methimazole).  Sometimes propylthiouracil (PTU) is prescribed but PTU has a higher risk of elevating liver enzymes compared to methimazole and MDs will prefer to prescribe methimazole (2).  If your thyroid hormones are very high and you are very symptomatic, your doctor may even recommend radioactive iodine which shuts down the thyroid, essentially “zapping” it.  Surgery to remove the thyroid gland is often another option.  Once either of these invasive procedures is done, one could become hypothyroid and then be prescribed Synthroid “for the rest of their life”.

Causes of Suboptimal Thyroid Hormones

The four major contributors that can lead to abnormal thyroid hormones are: Nutrient deficiencies; Adrenal dysfunction; Autoimmune; and, Cancer.  While allopathic medicine can help increase or decrease your T4 and/or T3 levels through medication, there is not much in allopathic medicine currently for lowering thyroid antibodies or addressing suboptimal adrenals if it isn’t overt Cushing’s syndrome (most common cause is iatrogenic – caused by too many corticosteroid medications) or Addison’s disease (rare).  MDs may recommend vitamins or minerals if they suspect your low thyroid hormone levels are due to an iodine or iron deficiency.

NUTRIENT DEFICIENCIES: Thyroid hormones contain iodine and in developing countries, where iodine deficiency is common, this is a leading cause for hypothyroidism. With the advent of iodized table salt in North America, it reduced the incidence of hypothyroidism, however, with the exposure to heavy metals and other environmental pollutants, this can decrease the ability of iodine to accumulate in the thyroid gland and form thyroid hormone.  The reduction in table salt usage may decrease iodine consumption as well.  Other nutrients like tyrosine (amino acid), zinc, copper, iron, vitamin E, vitamin B2, vitamin A, and selenium are necessary for forming T3 and T4 thyroid hormone.

Should everyone just take iodine, tyrosine, and iron then? Not necessarily.  Increased iodine levels can decrease thyroid function or induce hyperthyroidism.  Caution is necessary if you have an autoimmune thyroid condition such as Hashimoto’s as iodine may induce hypothyroidism (3).  Too much iron can be damaging to the body, and the use of tyrosine supplements, especially in autoimmune conditions does not have any concrete research.  Seeing a licensed healthcare provider can help you determine if iodine and tyrosine are necessary for improving your thyroid function or if optimizing other nutrients are necessary. Some functional medical doctors and naturopathic doctors offer functional testing to assess for environmental toxins, chemicals, and heavy metals (mercury, cadmium, lead, etc) in the body.

ADRENALS: This is a complex topic and there will be future blog posts regarding adrenal health. Your adrenal cortex produces the following hormones: cortisol, mineralocorticoids, DHEA, androgens (testosterone, etc), estrogen and progesterone.  Yes, males produce progesterone too and it helps to oppose estrogen – too much estrogen in men can create mood changes, weight gain, “man-boobs” (gynecomastia), and affect libido.  Progesterone is necessary as it is a precursor to cortisol, DHEA and testosterone.  The adrenals also release epinephrine – “flight or fright” neurotransmitter which promotes cortisol secretion.

Thyroid hormones and adrenals
The connection between your adrenals and thyroid and how cortisol can inhibit T3 formation and activity

During times of stress, these adrenals are in overdrive overproducing cortisol which can decrease levels of the other adrenal hormones.  Cortisol can affect the conversion of T4 to T3 and has also shown to affect peripheral tissue activity of T3.  Sometimes, this is why people who are put on Synthroid (T4) medication may continue to feel tired and not the best – they have poor T4 to T3 conversion – yet the doctor keeps increasing their Synthroid dose with only minimal improvement in symptoms.  If T4 to T3 conversion is impaired, this can produce rT3 which is T3’s cousin but has no function and prevents T3 from acting on its receptor sites.  Excess cortisol can also affect estrogen metabolism and estrogen dominance states can affect the amount of free T4 and free T3 in the blood leading to hypothyroid symptoms.  Another reason why it is so important to tell your doctor you want to test free T3 and free T4 – not just TSH.

AUTOIMMUNE: This is the hardest type of thyroid disorder to treat because it involves an inflammatory state and a hyperactive immune system that produces antibodies against certain enzymes or other thyroid gland proteins affecting the production of thyroid hormones.  The two autoimmune thyroid disorders are Hashimoto’s Disease ‘Hashi’s’ and Grave’s disease.  The latter is associated with hyperthyroidism.  In Hashimoto’s, one may start out in a hyperthyroid state and eventually end up in a hypothyroid state as the thyroid gland is damaged by the autoantibodies (4). MDs will treat these conditions the same way they treat general hypothyroidism or hyperthyroidism.

Naturopathic medicine aims at getting to the root cause and figuring out what part of your body decided to go “off-track” resulting in the autoimmune condition, not just increasing/decreasing thyroid hormones.  This could involve addressing your digestive health, hormonal imbalances, and working with you to shift your immune system to reduce immune hyperactivity, lower inflammation, and lower thyroid antibodies.  YES ladies, imbalances in progesterone and estrogen can affect thyroid function and predispose one to autoimmune thyroid disorders.  This is why many women will be diagnosed with a thyroid disorder in the perimenopausal stage or even post-partum.

Identifying food sensitivities and optimizing digestive health is a key area to investigate for any autoimmune condition, not just Hashimoto’s or Grave’s disease.  If you experience bloating, gas, acid reflux, and heartburn, there may be something going on in your gut.

CANCER: Yes, unfortunately, another factor to rule out if you have thyroid dysfunction is thyroid cancer. This is more common in females and most common in the 15-49 years range.  Exposure to ionizing radiation, a family history of thyroid cancer, having a personal history of other thyroid disorders, obesity and tall height are risk factors (5).  If you notice swelling on your neck in the thyroid region and your doctor assesses an enlarged thyroid or firmness over the thyroid during a physical exam, he or she will refer you to get an ultrasound.  If nodules are found, you may be referred for a biopsy to rule out a malignant vs benign nodule.  Benign nodules can be associated with autoimmune thyroid conditions and are monitored to ensure they do not become malignant.

Naturopathic Treatment Options

There are vitamins, minerals, and herbs to treat patients with suboptimal thyroid hormone levels.  Herbal supplements can be used to enhance thyroid function or to calm the thyroid but like medications, they can have toxicity symptoms and adverse effects which is why it is important to work with a trained healthcare provider so they can recommend treatments individualized to you.  During an initial visit, we will sit down and perform a thorough review of your health concern(s) and a head-to-toe review of symptoms which will help identify if it is a nutritional deficiency issue, a hormonal or a digestive issue that is leading to suboptimal thyroid function or we will do a workup to assess for thyroid dysfunction and assess the thyroid markers I mentioned above for an additional fee (many MDs will only run half of them or a reluctant to run anything else if TSH is in the normal reference range).

If you intuitively feel that there may be something wrong with your thyroid but your blood test results keep showing a TSH within the normal reference range (1-4.00), get another opinion.  There may be something else going on such as a nutrient deficiency, impaired liver detoxification, digestive problems, or suboptimal cortisol levels contributing to your symptoms.

Some tips you can start implementing right away at home to improve your thyroid health: 

  • Steam or cook your cruciferous vegetables – broccoli, cauliflower, cabbage, brussel sprouts – as this reduces some of the goitrogens that interfere with thyroid hormone production
  • Eat brazil nuts if you are not sensitive or allergic to them – these contain selenium which supports thyroid function
  • Find ways to reduce stress – meditation, music, dancing, being creative, exercise, etc – as this keeps your cortisol levels down


  1. Davenport, L. “Time for a U-turn on Levothyroxine? Overuse Is Rife, Say Docs” in Medscape Family Medicine. WebMD LLC:Nov 14 2016.  Retrieved on Nov 13 2018 from
  2. Nakamura H et al. Comparison of methimazole and propylthiouracil in patients with hyperthyroidism caused by Graves’ disease. J Clin Endocrinol Metab 2007 Jun; 92:2157-62.  
  3. Chung HR MD. Iodine and thyroid function.  Ann Pediatr Endocrinol Metab. 2014 Mar;19(1):8-12.
  4. Ferry R, Jr. MD. Hashimoto’s Thyroiditis Symptoms, Diet, and Treatment.  Retrieved on November 24 2018 from
  5. Canadian Cancer Society (2018). Thyroid Cancer.  Retrieved on November 23 2018 from
  6. Thyroid gland image from: Don Bliss. (2001). Thyroid Gland from National Cancer Institute. Retrieved on November 23 2018 from

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