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If you haven’t gotten to know your thyroid gland yet, it’s time to get acquainted. It may be small enough to hide under your chin’s shadow, but it plays a big role in whether you’re energetic or sleepy, lean or supple, calm or moody, warm or cold, and so much more.

Getting To Know Your Thyroid

Long before modern medicine identified the inner workings of the thyroid gland, traditional medicines like ayurveda and Chinese medicine recognized it as a key component of the body’s vitality. In Chinese medicine, an unhealthy thyroid is described as an imbalance in Qi, or life force. In ayurvedic medicine, the thyroid is at the center of the throat chakra, or spiritual energy center responsible for one’s ability to communicate and express the true self.

Did you know that every cell in your body depends on thyroid hormones to produce energy? Even before you were born, thyroid hormones were directing your brain development and growth. Your thyroid health can fluctuate throughout life, especially during times of stress. Because it impacts every part of your body, sometimes it’s hard to identify when thyroid dysfunction first begins. If you know what to look for, and which tests to request, you can catch it early. More on that later, but first, let’s break down how your thyroid works.

Thyroid Function

The thyroid gland is part of your endocrine system, a network of glands and organs that produce hormones to control your growth, metabolism, sexual function, and mood. Thyroid hormones have many jobs, but the most important one is metabolism. On a microscopic level, this means the thyroid tells your cells to use nutrients to make energy. On a larger scale, this leads to healthy body weight, energy levels, appetite, bones, and fertility.

Your brain monitors your thyroid hormones and sends a signal when it wants you to make more. This signal, sent from your pituitary gland to your thyroid, is called thyroid stimulating hormone (TSH). If your thyroid hormones are low (hypothyroidism), the brain yells a little louder and TSH rises. When you produce too much hormone (hyperthyroidism), that voice gets turned down, resulting in a low TSH.

The thyroid makes four important hormones, and three of them directly impact your energy and metabolism:

  • Thyroxine (T4): Inactive thyroid hormone doesn’t do much for metabolism, but makes up 80% of what the gland produces. Your body must convert T4 into T3 to stimulate metabolism.
  • Triiodothyronine (T3): Active thyroid hormone makes up 20% of what your thyroid produces. T3 has the greatest impact on metabolism and energy.
    Reverse Triiodothyronine (RT3): Reverses the effects of T3. You only make small amounts of RT3, but it can cause hypothyroidism symptoms if you make too much.
  • Calcitonin: A hormone that helps regulate calcium levels which affect bone, muscle, and nerve health. Luckily, most thyroid disorders don’t cause big changes in calcitonin levels.


To make these hormones, your thyroid needs healthy levels of three very important micronutrients: iodine, tyrosine, and selenium. When you don’t eat enough of these, your thyroid can’t do its job well. You need iodine and tyrosine to make T4, and selenium to convert T4 into the active T3. Most Americans unknowingly rely on processed foods containing iodized salt in order to reach healthy iodine levels. Because it’s important to limit processed foods in a healthy diet, make sure you have iodine-rich ingredients in your kitchen. Clinically, low iodine levels are surprisingly common, even in those following the most healthy, whole foods diets. With a few key added ingredients, anyone can correct the deficiency and maintain their healthy lifestyle.

Ready to support your thyroid hormone production through diet? Stock your kitchen with these foods:

  • For Iodine: Fish, shellfish, eggs, grass-fed dairy products, seaweed, iodized sea salt
  • For Tyrosine: Poultry, eggs, grass-fed cheese, avocados, peanuts, sesame seeds
  • For Selenium: Brazil nuts, fish, poultry, ham, brown rice

Whenever possible, use iodine rich foods and iodized sea salt rather than buying a supplement which may contain high doses. Even though you need iodine for a healthy thyroid, too much of this micronutrient can actually cause thyroid disease.

Now you understand how your thyroid works, but how do you know if you’re experiencing thyroid dysfunction? Remember, thyroid hormones fuel every cell in your body, so the symptoms may be hard to pinpoint.


Low T4 and T3 can be caused by micro-nutrient deficiencies and environmental toxins, but the most common cause in the U.S. is an autoimmune disease called Hashimoto’s Thyroiditis. In Hashimoto’s, your immune system attacks your thyroid, causing hormone fluctuations that lead to hypothyroidism.

Common Symptoms: Weight gain, fatigue, slow heart rate, constantly feeling cold, brain fog, decreased exercise endurance, hair loss, heavy periods, constipation, dry skin, muscle aches, and depression.


High T4 and T3 levels are sometimes caused by nodules, small growths in the gland that produce extra hormone, but they’re more likely to occur from thyroiditis (inflammation of the gland). This can be triggered by a virus or a recent pregnancy, but the more common cause is an autoimmune disease called Grave’s Disease. Just like Hashimoto’s, your immune system attacks your gland, but in a way that causes you to make too much T4 and T3.

Common Symptoms: Weight loss, racing or irregular heartbeats, constantly feeling overheated, shakiness, frequent bowel movements, shortness of breath, disappearing periods, nervousness, hair loss, and excessive sweating.

Even if you don’t have symptoms of thyroid dysfunction, getting a blood test for a baseline TSH by the time you’re 18 years old is important. And if you’re having symptoms, make sure your doctor knows that you want a full thyroid panel. Here are the recommended blood tests to ask for based on your symptoms:

If you have NO symptoms: TSH, Free T4, Free T3

If you have symptoms of hypothyroidism: TSH, Free T4, Free T3, Iodine Level, Reverse T3, Thyroid Peroxidase Antibodies, Thyroglobulin Antibodies

If you have symptoms of hyperthyroidism, or symptoms of both: TSH, Free T4, Free T3, Iodine Level, Reverse T3, Thyroids Stimulating Immunoglobulin, Thyroid Peroxidase Antibodies, Thyroglobulin Antibodies

When you look at your test results, remember that a “normal” range does not equal optimal. That recommended range is based on the scores of 95% of people who took the same test. Just because your number falls within normal, doesn’t mean it’s ideal for your health. My favorite example of this is TSH, the most commonly ordered thyroid test. Most labs provide a normal reference range of 0.4-4.0, but in my experience, most patients feel best when their TSH is between 1.0-2.0. Work with a provider willing to help you optimize and dig deeper into your health. Your numbers matter, but so do your symptoms.

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Dr. Kaley Bourgeois

Naturopathic Physician

Dr. Kaley Bourgeois is a Naturopathic Physician practicing holistic family medicine designed to strengthen the body’s natural healing processes. She’s experienced in the treatment of endocrine dysfunction, women’s health concerns, hormone imbalances for all genders, fertility support, weight loss, digestive health, and fibromyalgia & chronic fatigue syndromes. At Framework Integrative Medicine in Portland, OR, she offers individualized care that encompasses the best of both alternative and conventional medicine.