the hub of your metabolic system
Your thyroid is arguably one of the most important endocrine organs in the body. Sitting comfortably in the base of the neck, this exocrine gland outputs three major hormones: thyroxine (aka inactive T4), triiodothyronine (aka active T3) and calcitonin. These hormones essentially determine the body's metabolic rate at which it burns fuels like fat and sugar, synthesizes proteins, regulates heart rate, and controls development - especially in infancy. They also influence the hypothalamic-pituitary-adrenal axis which determines your response and resilience to stress.
Thyroid disorders are one of the most common hormonal issues plaguing Canadians, with hypothyroidism affecting roughly 2 in every 100 people, and prevalence rates increase with age.
"I sleep well but never wake feeling rested"
"I can't lose weight, no matter what
"I feel like I'm in a constant fog"
"My labs are normal, but I still feel unwell"
Hypothyroidism is described as under-functioning of the thyroid gland and can be a result of high levels of stress, environmental influence, genetics, age, and autoimmunity (Hashimoto's). Under-functioning of the gland, and/or failure of the negative feedback signalling to the brain ultimately result in a lack of T4/T3 hormones in the bloodstream, producing the following most commonly experienced symptoms:
Poor concentration or feeling mentally "foggy"
Muscle and joint aches
Prolonged or excessive menstrual bleeding in women
Hair loss, brittle hair, brittle nails
Hyperthyroidism is less common and is usually a result of an autoimmune disorder known as Grave's Disease. Symptoms include:
Decreased tolerance to heat
Tremors, heart palpitations and/or chest pain
What causes thyroid dysfunction?
low iron - the enzyme known as thyroid peroxidase, which is essential to thyroxine production is largely heme dependent. That means if your iron is low, your thyroid will have a hard time making T4
infection - inflammation of the thyroid gland, also known as thyroiditis, is often secondary to bacterial and viral infections like Staphylococcus aureus, Streptococcus, mycobacteria, and fungi
environment - heavy metals, chemical drug toxicity, synthetic hormones (especially high doses during fertility treatment) and BPAs/thermal receipts have all been linked to thyroid disorders
adrenal dysfunction - the hypothalamic-pituitary-adrenal axis has a closely linked relationship with thyroid function. High levels of cortisol output slow deiodinase activity, resulting in decreased T4 to T3 conversion and increased symptomatology of hypothyroidism.
iodine + selenium deficiency - iodine deficiencies remain the number one cause of goitre formation worldwide. Furthermore, selenium deficiencies have been shown to slow T3 conversion by up to 80%
insulin resistance - research from the American Thyroid Association confirms that individuals with insulin resistance have also been shown to have an increased number of thyroid nodules, and medications that support blood sugar control actually shrink the size of thyroid nodules. Furthermore, T4 to T3 conversion has been shown to be slowed by up to 50% in those with insulin resistance.
autoimmunity - Hashimoto's and Grave's disease are a result of autoimmune insult on the thyroid gland, enzymes, and receptors
Believe it or not, your thyroid medication can also be making your thyroid disorder worse. Increased levels of T4 in the system, without proper enzyme activity and support towards T3 production, can lead to T4 moving down the reverse T3 pathway, which inherently further inhibits thyroid function. Talk to Dr. Holmberg, ND about having your reverse T3 levels checked.
Testing your thyroid
The single most important thing to remember when screening for thyroid disorders is that while blood work is an essential part of uncovering underlying pathologies, it is not fool proof. Symptoms should always be evaluated first, and lab markers should be used to further confirm or deny underlying dysfunction.
Secondly, there are some things to remember when running your blood work.
3 Rules for an Accurate Diagnosis
#1 Always test your thyroid in the morning
#2 Always test your full thyroid panel (TSH, T4 and T3)
#3 Listen to your symptoms first, labs second
The most important blood markers to evaluate when assessing for a thyroid disorder are as follows:
TSH, Free T4, Free T3, reverse T3
Anti-TPO, Anti-TG, TSI antibodies
Ferritin and CBC
25-hydroxy Vitamin D
Fasting glucose + fasting insulin
DHEA, 4 point cortisol
Secondary to blood work, it is also important to assess your basal body temperature roughly 3 hours after waking. Temperatures under 98 degrees F can indicated slowed metabolic function.
Treatment of thyroid disorders
The first step to understanding and treating any hormonal concern is understanding if the issue comes from a supply issue (lack of building blocks to make the hormones), a conversion issue (inability to activate/utilize them), or if there's an absolute deficiency (in which case you much replace them). The goals of treatment include understanding the mechanism as to why the thyroid dysfunction is occurring, and implementing the proper diet, lifestyle, and supplement routine to correct the imbalance.
Therapies often include:
- Herbal medicine: support production and conversion, decrease antibodies in Grave's/Hashimotos
- Nutrient replacement: provide the building blocks (like zinc, iodine, selenium) to create hormones
- Diet and Lifestyle: eliminate food intolerances and promote healthy metabolism through diet
- Bio-identical Hormone Replacement Therapy (Natural Desiccated Thyroid) when necessary *
No two people are the same. Thyroid issues can present differently in everyone. Furthermore, lab testing is not always reliable. Some people exhibit symptoms of "subclinical hypothyroidism" well before lab tests become abnormal.
* Dr. Holmberg, ND is a licensed medical provider of bio-identical hormone replacement therapy