Thyroid is one of the most important endocrine organs in the body, producing three major hormones: thyroxine (inactive T4), triiodothyronine (active T3), and calcitonin. These hormones regulate the body’s metabolic rate, including the burning of fat and sugar, protein synthesis, heart rate, and developmental processes, especially during infancy. They also influence the Hypothalamic-Pituitary-Adrenal (HPA) axis, which determines our response and resilience to stress.

Potential Causes Thyroid Dysfunction

• Low Iron – thyroid peroxidase, enzyme essential to thyroxine production, is largely heme dependent. If iron is low, thyroid will have a hard time producing T4.
• Infection – thyroiditis, the inflammation of thyroid gland, is often secondary to infections such as Staphylococcus aureus, Streptococcus, mycobacteria, and fungi.
• Adrenal Fatigue – the HPA axis is closely linked with thyroid function. High levels of cortisol slow deiodinase activity, leading to decreased T4 to T3 conversion and increase symptoms of hypothyroidism.
• Iodine/Selenium Deficiency – iodine deficiencies is the number one cause of goiter formation across the world; and selenium deficiencies has been shown to slow T3 conversion by up to 80%
• Insulin Resistance – it is found to be correlate with increased number of thyroid nodules; T4 to T3 conversion has also shown to be slowed by up to 50% for those with insulin resistance.
• Autoimmunity – Hashimoto’s and Grave’s disease are result of autoimmune insult on the thyroid gland, enzymes, and receptors.
  
  

Assessment of Thyroid Dysfunction

Symptoms are evaluated first, lab markers are then used to further confirm or rule-out underlying dysfunction.

Some of the important blood markers for thyroid assessment – 

• TSH, Free T4, Free T3, reverse T3
• Anti-TPO, Anti-TG, TSI antibodies
• Ferritin and CBC
• 25-hydroxy Vitamin D
• Fating glucose & Fasting insulin

Treatment and Management

For any hormonal concerns, it is important to determine where the root of the dysfunction – 

• Supply issue – inability to produce hormones
• Conversion issue – inability to activate/utilize the hormones
• Absolute deficiency, where it must be replaced
• Autoimmunity eg Hashimoto’s or Grave’s disease
• Diet, gut health, food sensitivities
• Nutrient deficiencies
• Chronic stress and adrenal fatigue

Understanding the mechanism will shape the goals of treatment and help guide the implementation of proper diet, lifestyle and supplementation to correct the dysfunction. Thyroid treatments can also include herbal medicine, nutrient replacements, and Bio-identical Hormone Replacement Therapy (Natural Desiccated Thyroid) when necessary*.

*Dr. Sheena Wu, ND is a licensed medical provider of bio-identical hormone replacement therapy