The thyroid, a butterfly-shaped gland at the center of the front of your neck, is the master gland of metabolism. How well your thyroid is functioning is interrelated with every system in your body. If your thyroid is not running optimally, then neither are you.
Your thyroid powers every cell in your body through the hormones it produces. These hormones determine the energy level and reproduction of each cell, keeping your organs powered up and managing your overall metabolism. The process of creating, regulating, and delivering these hormones begins in your brain.
When your thyroid isn’t working properly, it can cause an array of issues. There are two primary types of thyroid disease: hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid).
The most common form of thyroid disease is hypothyroidism, which is when your thyroid is underactive and does not produce enough thyroid hormone. This can happen because your pituitary gland is malfunctioning and not sending enough Thyroid Stimulating Hormone (TSH) to your thyroid, or your TSH levels are normal, but your thyroid isn’t producing enough T4 and T3 to adequately fuel your cells.
10 Signs of an Underactive Thyroid
Weight gain or the inability to lose weight
Mood swings, anxiety, or depression
PMS, irregular periods, infertility, and low sex drive
Muscle pain, joint pain, carpal tunnel syndrome, or tendonitis
Dry or cracking skin, brittle nails, and excessive hair loss
Brain fog, poor concentration, or poor memory
Neck swelling, snoring, or hoarse voice
Cold hands and feet, feeling cold often, or low body temperature
On the other end of the thyroid spectrum is hyperthyroidism, which is less common yet more dangerous than hypothyroidism. When thyroid hormones are too high, energy metabolism will speed up, causing the body to burn through nutrients too quickly. This can result in malnutrition and lead to a wide range of problems. Grave’s disease is a form of hyperthyroidism.
14 Signs of an Overactive Thyroid
Hot flushes, sweating
Unintentional weight loss
Difficulty sleeping and insomnia
Elevated heart rate
Anxiety, irritability, or constant fatigue
Changes in menstrual cycle
Frequent stools, loose stool, or diarrhea
Thick red skin on shins and feet
Three methods to determine if you have a thyroid problem
Blood testing - This is the first step. In hyperthyroidism, the thyroid-stimulating hormone (TSH) will be very low and the Free T4 and Free T3 will be elevated. In autoimmune conditions, you will see elevated levels of antibodies as well.
Radioactive iodine uptake (RAIU) - This is the next step in diagnosing a thyroid imbalance. An RAIU using a small dose of I-131 will determine how much iodine the thyroid takes up. A high iodine uptake is indicative of Graves’ disease. This test can be helpful in ruling out other possible causes of an overactive thyroid.
Ultrasound - This is helpful to look at nodules on the thyroid, and your doctor may request you have a fine needle biopsy to confirm that the nodules are not cancerous.
Which Lab Tests are Best to Determine if You Have A Thyroid Problem?
It’s important that the results are read for optimal levels, not “normal” levels.
TSH levels: This test is based on the activity of the pituitary gland. High TSH levels indicate hypothyroidism whereas low TSH level indicates hyperthyroidism.
Free T4 (FT4): FT4 refers to the unbound T4 - i.e. the one found in the bloodstream. High FT4 levels indicate hyperthyroidism whereas low FT4 levels indicate hypothyroidism.
Free T3 (FT3): High FT3 indicates hyperthyroidism whereas low FT3 indicates hypothyroidism.
Reverse T3 (RT3): High RT3 levels indicate that there’s a high conversion of T4 to RT3 instead of FT3. This is an indicator of hypothyroidism.
Antibodies test (TPO - TgAb levels): Since the most common forms of thyroid disease are autoimmune diseases, detection of thyroid antibodies is essential to get an accurate result. There are two antibodies of concern: TPOAb and TgAb. TPOAb refers to the thyroid peroxidase antibodies that target the enzyme that mediates the iodination of thyroglobulin. TgAb refers to the antibodies that attack thyroglobulin.
What are the Optimal Lab Values?
TSH 1-2 UIU/ML or lower (Armour or compounded T3 can artificially support TSH)
FT4> 1.1 NG/DL
FT3> 3.2 PG/ML
RT3 less than a 10:1 ratio RT3:FT3
TPO - TgAb - <4 IU/ML or negative
What’s the difference between hyperthyroidism and hypothyroidism?
The most common form of thyroid disease is hypothyroidism, which is when your thyroid is underactive and does not produce enough thyroid hormone. In contrast, hyperthyroidism is when your thyroid produces too many thyroid hormones and energy metabolism will speed up, causing the body to burn through nutrients too quickly.
How to Understand Thyroid Levels
Your thyroid gland is one of the most integral organs in your body. It controls or plays a role in countless bodily functions to ensure your overall health, Understanding your thyroid levels can be confusing.
TSH isn’t a thyroid hormone, so why have this thyroid test? As mentioned, TSH is the hormone produced by the pituitary gland that tells the thyroid gland to start producing and secreting its hormones. While TSH levels fluctuate, significant changes can potentially act as an early warning sign of thyroid hormone issues.
TSH tests may detect high TSH levels, which might indicate that your thyroid isn’t making enough hormones, which can point to the autoimmune disease of hypothyroidism. Alternatively, a low TSH level in your blood may point to your thyroid overproducing hormones leading to the autoimmune disease of hyperthyroidism.
In other cases, TSH itself may contribute to a thyroid issue. Low TSH levels may prevent your thyroid from knowing that it needs to make more hormones, resulting in abnormally low thyroid hormone levels.
Total T4 levels are more prone to fluctuation, especially if you are on medication. Certain drugs and medical conditions can cause changes to thyroid hormone-binding proteins. Some can increase thyroid hormone-binding proteins, leading ot a higher total T4 level, while others reduce those proteins and result in lower total T4.
For these reasons, your healthcare provider or endocrinologist may recommend free T4 tests for a more accurate assessment.
T3 tests also come in free and total variations. However, free T3 levels generally aren’t reliable for diagnostic purposes. High total T3 levels typically point to hyperthyroidism. This makes total T3 tests important in diagnosing hyperthyroidism and determining the severity of the thyroid condition.
On the other hand, measuring T3 levels is less useful with the autoimmune thyroid disease of hypothyroidism. T3 levels only fall in later stages of hypothyroidism. In fact, people with severe hypothyroidism can have low free T4 levels and high TSH levels but completely normal T3 levels.
Measuring T3 and T4 levels is an accurate means of diagnosing certain thyroid disorders. For example, Graves’ disease typically presents with increased T3 levels compared to T4. Certain severe illnesses or the use of steroid medication can result in a lower proportion of T3 to T4.
HERE is a link to get a full thyroid test if you are concerned about any of these symptoms!
Keep Moving Forward 😊 Sarah