Thyroid School, Issue 3// Root Causes of Hypothyroid, Part 1

Last Thyroid School email, I introduced the different “types” of hypothyroidism. If you missed it, you can read more about it here.

Identifying your root cause is step one to best managing your unique hypothyroid situation because, guess what, there is no one-size-fits-all hypothyroid fix! Lacking clarity about your root causes is like setting out on a journey without an exact destination or map to help get you there.

To recap, the root cause(s) of hypothyroidism can first be split into two major groups:

1. Autoimmune

– Hashimoto’s

2. Not autoimmune

– Inadequate production of thyroid hormone (not enough thyroid hormone coming out)

– Cellular resistance to thyroid hormone (thyroid hormone being produced, but either not converting to “active” form and/or not being used by cells the right way)

So, the pressing question…

How do you identify what TYPE you may have? Get your labs out and put on your detective hat. I’ll wait…

Got your labs? Okay, good.

What you’re looking for are antibodies on your full thyroid panel. (Pssst… if you have hypothyroidism and are unsure if it is autoimmune in nature or not, you definitely want to get a full thyroid panel! You can request this through your provider. If you’re a 1:1 client or a Brain Fog Bootcamp: Thyroid member, I can help you with this if we haven’t already run one!).

The circled items are antibodies.

Do you have antibodies present above the recommended range? If so, you definitely want to chat with your doc about the likelihood of your root cause being a very common condition called Hashimoto’s. Some studies estimate that 90% of hypothyroidism is due to Hashimoto’s! Unfortunately, antibody levels aren’t always routinely run and/or rechecked. You may need to pull up old lab panels to see if antibodies levels were checked way back when you were first diagnosed.

Hashimoto’s is an autoimmune condition in which the body begins to attack the thyroid which affects the production of thyroid hormones.  It is the most common cause of hypothyroid among women in America and is 7 times more common in women than in men. Autoimmune management can be complex and generally includes a very individualized plan to eliminate inflammatory foods/food sensitivities, repletion of nutrients that are deficient, managing stress, and improving gut health to help control the confused immune system. (Detailed posts coming about this soon too!)

No antibodies present?

Here are some other common contributors to hypothyroidism:

1. High amounts of stress (it has a lot to do with the hypothalamus-pituitary-adrenal-ovary-thyroid axis… what a mouthful!!). Stress hormone and thyroid production oppose one another: the higher the stress, the less robust the thyroid.

2. Iodine Deficiency

 More commonly in underdeveloped countries, goiters (or an enlargement) can occur on the thyroid related to lack of iodine in supply in the diet. In America, where salt is iodized (meaning iodine is added), iodine deficiency is less common. Iodine is also present in foods such as seafood, eggs, seaweeds, navy beans, yogurt, strawberries, raw cheese, and potatoes. 

Too much of a good thing isn’t a good thing though, as taking in too much iodine can exacerbate hypothyroidism, especially if it is autoimmune in nature. The iodization of salt in America has reduced instances of iodine deficiency, but can also contribute to excess levels if eaten in abundance. Popular “thyroid supplements” usually contain high amounts of iodine. Knowing whether you’re iodine deficient and/or if you have autoimmunity can help to make an educated decision as to whether a thyroid-specific supplement is right for you.

3. Pregnancy

Pregnancy increases the demand on the thyroid, so if you were a bit sluggish to begin with, chances are that the trend can continue, so you may need more thyroid support (either introduction of medication for the first time or increasing your dose). Sometimes, during and after pregnancy, fluctuating levels of hormones can increase antibodies that attack the thyroid and result in postpartum thyroiditis. (Fun fact: some sex hormones increase immune activity and some decrease it. That’s why women are more predisposed to autoimmunity!)

4. Congenital Disease

Some babies are born with a defective thyroid gland or have inherited the disorder from one or both parents.

5. Estrogen Dominance or Excess Estrogens

High levels of estrogen can reduce levels of active thyroid by increasing TBG (thyroid binding globulin).  “Estrogen Dominance” (or having too high a ratio of estrogen to the other sex hormones) is increasing in prevalence due to synthetic estrogen-like hormones, called “xenoestrogens” creeping into our diet through modern day factory farming practices, more use of plastic products, synthetic hormone replacement, and reduced function of detoxification pathways in the body.

Xenoestrogens can be stored in the fat cells for decades and concentrate in fatty areas such as breast tissue. Excess fat produces estrogen hormone, so having too much body fat can further exacerbate high estrogen levels.  Signs of estrogen dominance include weight gain, menstrual irregularities (heavy, painful, cloth periods), poor memory, loss of libido, breast tenderness, fluid retention, and bloating. Constipated? Your risk of estrogen dominance increases significantly since the bowels are the #1 means of detoxification.

Over the next several Thyroid School posts, I’ll be continuing the conversation about root causes of hypothyroidism, specifically discussing poor thyroid hormone production and thyroid conversion next.

Disclaimer: Please note that “Thyroid School” emails from Chews Food Wisely, LLC (and Nicole Fennell, RD) are not intended to create any physician-patient relationship or supplant any in-person medical consultation or examination. Always seek the advice of a trained health professional with any questions you may have regarding a medical condition and before seeking any treatment. Proper medical attention should always be sought for specific ailments. Never disregard professional medical advice or delay in seeking medical treatment due to information obtained in “Thyroid School” emails. Any information received from these emails is not intended to diagnose, treat, or cure. These emails, websites, and social media accounts are for information purposes only. The information in these emails, websites, and social media accounts are not intended to replace proper medical care.

Hey There, I'm Nicole!

Nicole Fennell is a functional nutrition dietitian and fellow Hashimoto's patient with first-hand experience navigating the ups and downs of living with thyroid and immune system dysfunctionn. Her unique approach to nutritional management of chronic disease and nagging symptoms includes focusing on nourishing and building the body up versus tearing it down with low-calorie diets and high amounts of exercise.

Nicole has a real food approach and believes healthy eating, physical activity, and peace of mind are key to disease prevention and management. In her spare time, Nicole enjoys being active with her husband and three kids, lifting weights, practicing yoga, walking cooking, eating, and being outdoors.
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