Is Your Thyroid Behind Your Energy Levels, Mood Changes, or Metabolic Issues?

A guide to testing for both underactive and overactive thyroid conditions by Lesley Oakes.

Fatigue, brain fog, weight changes, digestive issues, overheating or feeling cold all the time…

There are many things that can cause these symptoms, and some people spend years going from doctor to doctor trying to figure out why their test results come back normal, when their symptoms are not normal. Often, that’s when they might find themselves in a consultation with me, discovering these symptoms are all connected to the thyroid gland.

About the Thyroid Gland

Your thyroid is about the size of a walnut and is located near your throat. It produces hormones that regulate metabolism, temperature, energy production, digestion, menstrual health, cognitive function, and emotional wellbeing.

So when your thyroid isn’t functioning properly - either underactive or overactive - the effects ripple through the whole body.

Here at PNMC, I frequently see clients who have been told their thyroid is “fine” despite symptoms clearly indicating otherwise. Some doctors can and do test for the broader thyroid hormone panel, but generally speaking, it is only TSH that is routinely tested as a measure of thyroid health.

In this article I’ll share more about:

• Symptoms of an underactive and overactive thyroid

• Tests I recommend when symptoms are present

• How nutrient testing can provide important clues

• How naturopathic treatments can support thyroid health naturally

Underactive Vs Overactive Thyroid

UNDERACTIVE THYROID (Hypothyroidism)

When the thyroid slows down, so does everything else in the body. Common symptoms include:

• Persistent fatigue or waking up feeling tired

• Unexplained weight gain or difficulty losing weight

• Cold intolerance, cold hands/feet

• Constipation or sluggish digestion

• Dry skin or hair changes

• Brain fog, forgetfulness, poor concentration

• Low mood, feeling “flat” or unmotivated

• Feeling slowed down physically or mentally

These symptoms are common, yes, but they’re not normal. If you’re experiencing these symptoms its not something you need to just push through, and not something likely to go away on its own.

OVERACTIVE THYROID (Hyperthyroidism)

When the thyroid becomes overactive, everything speeds up, and while many would prefer a fast metabolism, it can be quite unpleasant when the thyroid is overdoing it. 

Common symptoms of an overactive thyroid include:

• Unexpected or uncontrollable weight loss despite normal food intake

• Feeling wired, anxious, or “on edge”

• Heart palpitations or a racing pulse

• Heat intolerance, sweating easily

• Loose stools or frequent bowel movements

• Tremors or shakiness

• Difficulty sleeping

• Irregular menstrual cycles

• Irritability or emotional volatility

Because some symptoms mimic anxiety, perimenopause, or other conditions, hyperthyroidism is frequently missed without proper testing.

What I Recommend Testing if Thyroid Issues are Suspected

A basic TSH test is not enough. At PNMC, we investigate a wider panel to better understand:

• Thyroid hormone production

• Conversion of T4 to active T3

• Stress-related metabolic slowdown

• Any presence of autoimmune thyroid disease

• Nutrient drivers of thyroid imbalance

Here’s the breakdown of why it’s so important to test all of these.

1. TSH (Thyroid Stimulating Hormone)

This hormone is the brain’s signal to the thyroid gland..

• High TSH often means an underactive thyroid

• Low TSH often points to an overactive thyroid

But on its own, TSH cannot explain why symptoms are present.

2. Free T4 (Thyroxine)

The main hormone produced by the thyroid.

• Low T4 can indicate underactive thyroid

• High T4 suggests overactive thyroid

3. Free T3 (Triiodothyronine)

The active hormone that drives metabolism, temperature, and energy.

• Low T3 can occur even when TSH and T4 look normal

• High T3 is common in hyperthyroidism

4. Reverse T3

We can consider this the “brake pedal” hormone. Reverse T3 levels are often elevated when:

• You’re stressed

• Recovering from illness

• Restricting calories

• Dealing with chronic inflammation

High reverse T3 can block T3 activity and mimic hypothyroidism.

5. Thyroid Antibodies (TPO & TgAb)

These identify the autoimmune thyroid conditions Hashimoto’s (causes underactive thyroid) and Graves’ disease (causes overactive thyroid). Autoimmune thyroid issues often require a very different treatment approach to hypo- or hyperthyroidism..

Nutrient Testing For Thyroid Support

Thyroid hormones rely on specific nutrients to work optimally.. Deficiencies in these key nutrients can cause or worsen symptoms of both hyper and hypo thyroid patterns. Testing the levels of these nutrients in your body provides more information for us to put together a clear picture of root causes.

Iodine - Essential for thyroid hormone production. A simple urine test can identify deficiency.

Selenium - Crucial for T4 → T3 conversion and for lowering thyroid antibodies.

Zinc - Supports immune balance, hormone metabolism, and skin repair. I like to look at Zinc and Copper levels in a blood test as low zinc and elevated copper can both negatively affect the thyroid.

Iron (Ferritin) - Low iron stores mimic hypothyroid symptoms and worsen fatigue. I recommend getting your iron levels tested through your GP - and often this will be one of the first things tested if you’re reporting fatigue and low energy levels.

Vitamin D & B12 - Both support energy, immune health, and hormone function.

Why Testing Matters

We can arrange for a comprehensive functional medical lab test and reporting when you come to a consult, but you can also make the most of the tests that your GP is able to order for you, such as Zinc, copper, vitamin D and iron levels, which may be covered under medicare.  

Thyroid imbalances, whether overactive or underactive, can affect your:

• Metabolism

• Mood and cognitive function

• Menstrual cycles

• Energy levels

• Stress resilience

• Skin, hair, and nails

• Digestion

• Body temperature

Many clients come to me after years of hearing “your blood tests are normal” while still feeling exhausted, flat, or unwell.

A comprehensive thyroid work-up helps us to understand:

• Is your thyroid underactive or overactive?

• Is your body converting hormones properly?

• Are nutrients (or lack of) contributing to your symptoms?

• Is an autoimmune process involved?

• What is actually driving your weight, mood, or energy changes?

From here, we create a personalised naturopathic treatment plan, which may include:

• Nutrition support - food to avoid, or include more of in your diet  

• Herbal medicine - liquid tonics or tablets

• Supplementation with the highest quality products

• Gut and liver support to assist elimination pathways

• Stress management - including specific herbs or supplements to support this

• Lifestyle guidance

Thyroid health can be restored, and with decades of experience helping countless patients get back to full health, I can assure you that not only are you not alone in this, but by understanding what is causing symptoms and with the right support, you’ll be on the path to recovery before you know it. 

Ready to understand your thyroid and reclaim your energy?

When you book a consultation with me I assess your symptoms and can start to put together a picture of what may be happening to cause this. I can also offer comprehensive thyroid testing which provides specific information to enable us to pinpoint exactly what is happening and what you need to address these symptoms.

To book your appointment, either call the clinic on 08 9328 9233 or find a time through our online booking system.

Stop guessing and start understanding your symptoms, so you can feel your best again.