The Root Causes of Thyroid Imbalance

The thyroid is a small gland with a very big job.

Located at the front of your neck, the thyroid produces hormones that help regulate metabolism, energy production, heart function, digestion, body temperature, brain function, bone health and much more.

Thyroid hormones also influence mitochondrial function—the tiny energy-producing centers inside your cells—which helps explain why changes in thyroid function can affect so many different areas of the body.

When thyroid function slows down, you may notice fatigue, feeling cold, constipation, dry skin, hair changes, brain fog, weight changes or difficulty maintaining your normal energy.

But here's something I think is important:

Having thyroid symptoms doesn't automatically tell us why your thyroid isn't functioning optimally.

That's where I like to dig deeper.

Looking Beyond TSH

Thyroid disorders are incredibly common, yet many patients come into my office after having only a TSH test performed.

TSH is important, but it doesn't always give us the complete picture.

Depending on the patient and clinical situation, I may want to look at additional markers such as Free T4, Free T3 and thyroid antibodies, along with other laboratory markers that can help us understand what's happening elsewhere in the body.

From a functional medicine perspective, I also want to consider things that may influence thyroid health, including nutrient deficiencies, autoimmune disease, metabolic health, medications, stress, liver function and environmental exposures.

Instead of simply asking:

“Is your TSH normal?”

I want to ask:

“Why are you experiencing these symptoms in the first place?”

Here are eight areas I consider when evaluating thyroid health.

1. Thyroid Gland Dysfunction

Sometimes the problem really does begin with the thyroid gland itself.

In primary hypothyroidism, the thyroid isn't producing adequate thyroid hormone despite receiving signals from the pituitary gland to do so.

One of the most common causes of hypothyroidism in the United States is Hashimoto's thyroiditis, an autoimmune condition in which the immune system targets thyroid tissue.

Other factors can also directly affect the thyroid gland, including certain medications, thyroid surgery, radiation treatment and significant abnormalities in iodine intake.

The important part is determining what type of thyroid dysfunction is actually occurring rather than assuming every case of hypothyroidism has the same cause.

2. Pituitary Dysfunction

Your thyroid doesn't work alone.

It is part of a communication system between your hypothalamus, pituitary gland and thyroid, commonly referred to as the HPT axis.

The pituitary produces thyroid-stimulating hormone, or TSH, which tells the thyroid to produce thyroid hormones.

If pituitary function becomes impaired, that signal can be disrupted.

Pituitary disorders are much less common than primary thyroid disease, but tumors, traumatic brain injury, surgery, radiation and other medical conditions can affect pituitary hormone production.

This is one reason thyroid labs need to be interpreted together rather than looking at one number in isolation.

3. Hypothalamic Dysfunction

The hypothalamus is a small but incredibly important area of the brain that helps connect the nervous system with the endocrine system.

It plays a role in temperature regulation, appetite, sleep, stress responses and hormone signaling.

The hypothalamus communicates with the pituitary, which then communicates with the thyroid.

Significant injury or disease affecting the hypothalamus can therefore interfere with this signaling pathway.

True hypothalamic thyroid dysfunction isn't something I assume every fatigued patient has, but understanding the brain-pituitary-thyroid connection helps illustrate why thyroid health is much more complex than simply looking at the thyroid gland itself.

4. Thyroid Hormone Conversion

Your thyroid produces primarily T4, which is considered a relatively inactive thyroid hormone.

Your body then converts T4 into T3, the more biologically active form of thyroid hormone.

This conversion occurs in several tissues throughout the body, including the liver and kidneys.

Illness, inadequate calorie intake, certain medications and other physiological stressors can influence thyroid hormone metabolism.

This is one reason I like looking at the whole patient rather than assuming that every thyroid symptom means the thyroid gland itself isn't working.

Your thyroid hormones have to be produced, transported, converted and ultimately used by your tissues.

There are several steps in the process.

5. Autoimmune Thyroid Disease

Autoimmunity is an extremely important part of the thyroid conversation.

Hashimoto's thyroiditis is an autoimmune condition associated with hypothyroidism, while Graves' disease is an autoimmune condition that typically causes hyperthyroidism.

Depending on the clinical picture, thyroid antibody testing may include thyroid peroxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb) and, when Graves' disease is suspected, TSH receptor antibodies.

When autoimmune thyroid disease is present, I don't only want to look at thyroid hormone levels.

I also want to consider the bigger picture, including gut health, nutrient status, inflammation, stress, sleep and other autoimmune conditions.

What About Gluten and Hashimoto's?

This is an area where I think we need more nuance than simply telling every person with Hashimoto's that gluten is automatically the problem.

There is a well-established relationship between celiac disease and autoimmune thyroid disease, so screening for celiac disease may be appropriate in certain patients.

Some people with Hashimoto's also report feeling better when they remove gluten, particularly when celiac disease or gluten sensitivity is present.

But I don't believe every patient needs exactly the same diet.

I would rather determine what is appropriate for the individual than hand everyone the same list of foods they're never allowed to eat again.

Food should give us information—not anxiety.

6. Chronic Stress and the Thyroid

Stress is another piece of the puzzle.

Your stress-response system and thyroid system communicate with one another, and prolonged physiological stress can influence many processes that affect how you feel—including sleep, blood sugar, digestion, inflammation and energy.

This doesn't mean that every thyroid disorder is caused by “adrenal fatigue.”

That's terminology I no longer use.

Instead, I look at the HPA axis, nervous system regulation and the overall physiological stress load on the body.

This is also where acupuncture can be a valuable part of a comprehensive treatment plan.

Acupuncture can help support relaxation and autonomic nervous system regulation, which is one reason I frequently incorporate it when thyroid symptoms occur alongside stress, anxiety, poor sleep or that familiar tired-but-wired feeling.

Sometimes supporting thyroid health also means helping the rest of the body stop behaving as though it's being chased by a tiger all day.

7. Nutrient Deficiencies

Your thyroid requires specific nutrients to produce and metabolize thyroid hormones.

Two of the most important are iodine and selenium, but iron, zinc and other nutrients also play roles in normal thyroid physiology.

This doesn't mean everyone with thyroid symptoms should immediately start taking iodine.

In fact, too much iodine can be problematic, particularly in susceptible individuals with autoimmune thyroid disease.

This is where testing and individualization become important.

Selenium can be found in foods such as seafood, meat, eggs and Brazil nuts, while iodine is commonly obtained from iodized salt, seafood, dairy products and sea vegetables.

I prefer looking at the overall diet and clinical picture before assuming someone needs high-dose supplementation.

More isn't always better when it comes to thyroid nutrients.

8. Environmental and Heavy Metal Exposure

Environmental exposures are another area worth considering, particularly when there is a known occupational, dietary or environmental risk.

Certain heavy metals and environmental chemicals have been studied for their potential effects on thyroid hormone production, metabolism and signaling.

But I would not assume heavy-metal toxicity is the root cause of every thyroid problem.

Exposure history matters.

Do you work around certain chemicals or metals?

Is there a known environmental exposure?

What types of fish are you eating and how frequently?

Are there other clinical findings that make exposure worth investigating?

When testing is appropriate, it should be selected carefully and interpreted in context.

And I definitely don't recommend jumping into aggressive “detox” protocols simply because someone feels tired and has an abnormal thyroid marker.

First we investigate.

Then we decide what actually needs to be addressed.

What If You're Taking Thyroid Medication but Still Don't Feel Well?

This is something I hear frequently.

A patient may be taking levothyroxine or another thyroid medication, their TSH may fall within the laboratory reference range, and yet they still don't feel like themselves.

That doesn't automatically mean the medication isn't working.

It may mean we need to look beyond the thyroid.

Fatigue, brain fog, hair loss, constipation, difficulty managing weight and feeling cold can overlap with many other conditions.

Depending on the patient, I may want to consider iron status, vitamin B12, vitamin D, blood sugar regulation, sleep, perimenopause or menopause, digestive health, medications, nutrition and other hormone patterns.

Sometimes the thyroid is part of the story.

Sometimes there are several stories happening at once.

That's why I don't like treating laboratory numbers without listening to the person sitting in front of me.

A Functional Medicine Approach to Thyroid Health

Functional medicine asks us to look beyond the diagnosis and understand the factors that may be contributing to the patient's symptoms.

That doesn't mean replacing conventional thyroid treatment.

Thyroid medication can be extremely important and necessary for many patients.

Instead, my goal is to ask what else may need attention.

Is autoimmunity involved?

Is there a nutrient deficiency?

Is iron low?

Is blood sugar poorly regulated?

Is the patient sleeping?

Is there chronic physiological stress?

Are digestive problems affecting nutrient intake or absorption?

Is she entering perimenopause and assuming every new symptom must be her thyroid?

That last one comes up more often than you might think.

The answers help us create a much more individualized plan.

Dr. Stephanie's Tip: If you have thyroid symptoms, don't become obsessed with one laboratory number.

TSH gives us useful information, but it's only one piece of the clinical picture.

Look at your symptoms, your thyroid hormones, antibodies when appropriate, nutrient status and what else is happening throughout your body.

And if someone tells you that one single thing—gluten, cortisol, toxins, your liver, your adrenals—is definitely the cause of every thyroid problem you have, I'd keep asking questions.

The body is usually more interesting than that.

Getting to the Root of Thyroid Symptoms

Thyroid health isn't simply about whether your thyroid is “high” or “low.”

The thyroid communicates with your brain, immune system, metabolism and the rest of your endocrine system, which is why I prefer looking at the whole picture.

At New Direction Natural Medicine in Altamonte Springs, I use functional medicine alongside acupuncture and Chinese medicine to help patients better understand the patterns behind their symptoms.

When appropriate, we can use comprehensive laboratory testing to look more closely at thyroid function and other factors that may be contributing to fatigue, brain fog, digestive changes, hormone symptoms and changes in metabolism.

The goal isn't to chase every possible “root cause.”

It's to identify the factors that actually matter for you.

If you're looking for a root-cause approach to thyroid and hormone health in Altamonte Springs, Orlando or the surrounding Central Florida area, schedule a consultation at New Direction Natural Medicine.