Introduction

It is estimated that 1 in 10 Canadians have some form of thyroid disease, many of which have not yet been diagnosed. The most common thyroid condition in Canada is hypothyroidism due to Hashimoto’s thyroiditis (HT).

“Hashi – what’s this now? Who? But I’m not Japanese!? I’ve never heard of that before.”

Yes, this is the patient’s typical follow-up response to this unusual-sounding diagnosis.

HT is an immune-mediated reaction directed against the thyroid gland causing inflammation and destruction of functional thyroid tissue. This process typically results in hypothyroidism (under-functioning thyroid gland), at which point thyroid medication is often prescribed. HT was the first autoimmune disease ever identified. And by whom? You guessed it – Japanese medical scientist Hakaru Hashimoto in 1912.

What is Autoimmunity?

Basically, this is an abnormal response by the immune system whereby our own body becomes targeted. “Auto” in this case means “self”. Depending on the specific type of autoimmune disease (there have been around 50 identified), the immune system can inappropriately target a particular tissue or organ, or it can be relatively widespread. The incidence of autoimmune disease has been increasing for every age group in Canada. Acquiring more than one autoimmune disease is not uncommon; in fact there is an association between HT and rheumatoid arthritis, polymyalgia rheumatica, systemic lupus erythematosus, systemic sclerosis, Sjogren syndrome, and type 1 diabetes mellitus.

Although there has not been a single identified cause of autoimmune disease, there are several factors that seem to play a role in the development of Hashimoto’s thyroiditis:

Environmental factors
–  chemical exposure to tobacco smoke, polychlorinated biphenyls (PCB’s), solvents, toxic (“heavy”) metals
–  high iodine intake
–  radiation exposure
–  selenium deficiency
–  Vitamin D deficiency
–  certain drugs and medications (eg. interferons, amiodarone, antiretrovirals)

Genetic factors
–  several genes seem to play a role in the susceptibility of HT
–  HT is 10-15 times more common in women than men

Gastrointestinal factors
–  intestinal bacteria composition
–  infections such as Yersinia enertocolitica, Coxsackie B virus, retroviruses, Helicobacter pylori, Hepatitis C virus
–  food reactions such as anti-gliadin antibody formation

There are various signs, symptoms, and complications of untreated Hashimoto’s thyroiditis:

–  fatigue
–  weight gain
–  dry skin
–  constipation
–  cold intolerance
–  puffiness and fluid retention
–  brittle nails
–  enlarged thyroid gland (goiter)
–  depression
–  poor memory
–  aches & pains
–  menstrual irregularities
–  anemia
–  high cholesterol and heart disease
–  reduced kidney function

I have several of these signs and symptoms – how can I tell if I have Hashimoto’s thyroiditis?

There are a number of blood markers that are useful for assessing the thyroid. TSH (thyroid stimulating hormone) is typically part of a family doctor’s regular blood test requisition, however thyroid antibodies are not routinely tested. I frequently find benefit running a comprehensive panel including thyroid antibodies to identify these autoimmune reactions before the patient progresses to overt hypothyroidism.

Can Hashimoto’s thyroiditis be reversed?

Although many patients are told that they will need medication for life as a result of their HT, that has not been my clinical experience. I have frequently helped people improve their thyroid function, minimize hypothyroid symptoms, and normalize their thyroid lab markers through addressing many of the underlying factors listed above.

~ Dr. Tim Warwick, ND

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