If you suspect that you may have a thyroid condition, or know someone who does, this article will go over all of the most helpful tests that can help you identify a thyroid condition.
Basic Thyroid Tests
There are many blood tests that can be done to assess thyroid function, and I have found the following tests to be the most useful: TSH, Free T3, Free T4 and thyroid antibodies. In addition, the following tests should be considered as well:
- Medication history (antibiotics, NSAIDS, PPIS, steroids)
- Family history screen for thyroid and autoimmune conditions
- Toxicity exposure test
- Systemic inflammation tests
- Diagnostic gut test
- Ultrasound for Hashimoto’s
We will go over the standard tests and discover why the additional tests are often necessary to create a complete, holistic picture of your thyroid and overall health.
The Thyroid Screening Test
TSH (Thyroid Stimulating Hormone) – This is a pituitary hormone that responds to low/high amounts of circulating thyroid hormone.
In advanced cases of Hashimoto’s and hypothyroidism, this lab test will be elevated. In the case of Graves’ disease and hyperthyroidism, the TSH will be low. Interestingly, people with Hashimoto’s and central hypothyroidism may not have anything show up on this test.
Thyroid Hormone Level Tests
FREE T3 and FREE T4– These tests measure the levels of active thyroid hormone circulating in the body. When these levels are low, but your TSH tests in the normal range, might be indicative of a rare type of hypothyroidism known as central hypothyroidism.
Thyroid Antibodies
If thyroid antibodies are present, it means the immune system thinks the thyroid gland is a foreign invader, and it should be removed! These antibodies can be detected for decades before changes in the other blood tests are seen.
Thyroid Ultrasound
Some individuals might have a condition with their thyroid, but bloodwork doesn’t show anything. A thyroid ultrasound will help you determine what is really going on (shrunken thyroid, enlarged thyroid, or abnormal growths).
Medication history
- Medications for epilepsy (phenobarbital, carbamazepine or phenytoin)
- The antibiotic, rifampicin
- Imatinib (a tyrosine kinase inhibitor used to treat certain cancers)
- Estrogen replacements
- Amiodarone
- Glucocorticoids and some beta blockers
- NSAIDS (like Ibuprofen)
- PPIS (Proton Pump Inhibiters)
- Steroids
Family history screen for thyroid and autoimmune conditions
Genetics can play a large part in determining the likelihood of developing thyroid conditions in your life. Doing a proper family history and/or genetic screening should be considered as part of a workup.
Toxicity exposure test
To check if toxicity is causing thyroid issues, the following tests might be administered to symptomatic patients:
- Complete blood count
- Electrolytes (eg, calcium, magnesium, phosphorous)
- Urinalysis
- Serum acetaminophen level (in patients with intentional exposures and suicidal ideations)
- Arterial blood gas (ABG)
Systemic inflammation tests
C-reactive protein or CRP is an inflammatory protein that is one of the best ways to measure your inflammation levels. Produced mainly by the liver, we all make CRP and in normal levels, CRP helps fight off infections and protect your body.
Inflammation becomes damaging when it flares unchecked, like a forest fire fueled by gasoline. The CRP test measures your inflammatory firestorm.
Diagnostic gut test
A diagnostic gut test is important in determining your overall gut health. All of our organs are connected and influence each other. What ends up toxic to your gut might end up toxic in your bloodstream, and toxic to your thyroid. Often times, as a functional medicine doctor, I am concerned with leaky gut. To determine leaky gut, an intestinal permeability test can be administered.
Increased intestinal permeability (leaky gut) of the small intestine can:
- Increase the number of foreign compounds entering the bloodstream
- Allow bacterial antigens capable of cross-reacting with host tissue to enter the bloodstream, leading to auto-immune processes
- Enhance the uptake of toxic compounds that can overwhelm the hepatic detoxification system and lead to an overly sensitized immune system
Leaky gut has been observed in a range of disorders such as:
- Inflammatory Bowel Disease (IBD)
- Food allergy
- Inflammatory joint disease
- Chronic dermatologic conditions
Your Symptoms
Do you have any of the following? Many of these are indicative and valid tests to look at when it comes to diagnosing thyroid issues:
Hypothyroidism:Â Tangled hair, hair loss, eyebrow thinning/loss, puffy face, brain fog, sadness/apathy, fatigue, cold intolerance, weight gain, joint pain, heavy periods?
Hyperthyroidism: Irritability, agitation, mood swings, restlessness, palpitations, heat intolerance, rapid heart rate, scant periods, weight loss, insomnia, excess sweating?
Interpreting Your Labs
So once you have your labs, what do you do with them? What do they mean? Here is a chart to help you make sense of your numbers:
Â
Test Name | Standard Reference Range | Optimal Reference Range |
TSH | 0.4-5.5 IU/L | 0.5-2 IU/L, 0.5-2.5 IU/L in elderly |
Free T4 | 9-23 pmol/L | 15-23 pmol/L |
Free T3 | 3-7 pmol/L | 5-7 pmol/L |
Reverse T3 | 11-21 ng/dl | 11-18 ng/dl |
TPO Antibodies | ||
TG Antibodies |
Â
Thyroid Lab Analysis
- Lab Results:
TSH – Normal / Free T3 – Normal / Free T4 – Normal / TPO/TG Antibodies – Negative
Meaning: Normal Thyroid Unless Symptomatic – This is an indication that the person is euthyroid (has thyroid function at the normal level), with a low risk of Hashimoto’s/Graves’. I recommend double checking the reference ranges for optimal levels (see below), testing reverse T3, and doing a thyroid ultrasound if you still have thyroid symptoms. Adrenal saliva testing is the next step if all thyroid labs come back normal.
Â
- Lab Results:
TSH – Normal / Free T3 – Low / Free T4 – Low / TPO/TG Antibodies – Positive or Negative
Meaning: Central hypothyroidism – For some reason, the thyroid and the pituitary are not communicating. Autoimmune thyroid disease may be present.
Â
- Lab Results:
TSH – Normal / Free T3 – Normal / Free T4 – Normal / TPO/TG Antibodies – Positive
Meaning: Euthyroid Hashimoto’s – Your thyroid is still making enough thyroid hormone but is under attack. Stage 2 of Hashimoto’s. A thyroid ultrasound can be helpful here.
Â
- Lab Results:
TSH – Elevated / Free T3 – Normal / Free T4 – Normal / TPO/TG Antibodies – Positive or Negative
Meaning: Subclinical hypothyroidism – Your thyroid is losing its ability to make enough thyroid hormone. Stage 2 Hashimoto’s. A thyroid ultrasound can be helpful here.
Â
- Lab Results:
TSH – Elevated / Free T3 – Low / Free T4 – Low / TPO/TG Antibodies – Positive or Negative
Meaning: Hypothyroidism –Your thyroid has lost its ability to make enough thyroid hormone. Stage 3 Hashimoto’s. A thyroid ultrasound can be helpful here.
Â
- Lab Results:
TSH – Low / Free T3 – Normal / Free T4 – Normal / TPO/TG Antibodies – Positive or Negative
Meaning: Subclinical hyperthyroidism – Your pituitary is telling the thyroid to make less thyroid hormone.
Â
- Lab Results:
TSH – Low / Free T3 – High / Free T4 – High / TPO/TG Antibodies – Positive or Negative
Meaning: Hyperthyroidism –Your pituitary is telling the thyroid to make less thyroid hormone because it has detected excess levels of thyroid hormone.
The Bottom Line…. GET TESTED!
We are here to serve!
Call us at 319-393-4307 to schedule a 15-minute free strategy call!