Perhaps you -- or a friend or family member -- has suffered from some of the following mild symptoms: fatigue, dry skin, weight gain, cold intolerance, depression, or poor memory. There are so many possible causes for these kinds of symptoms that it is easy to assume you're "just not getting enough sleep," or that you're "just feeling a little stressed." January is Thyroid Awareness Month, so let's discuss a condition that is all-to-often overlooked: subclinical hypothyroidism (also called "mild thyroid failure").
The thyroid is a butterfly-shaped endocrine gland located at the base of your throat. This tiny organ has a huge responsibility; it makes thyroid hormones, which are secreted into the blood and then carried to every tissue in your body. Thyroid hormones regulate your metabolism, which helps your body use energy, maintain proper temperature, and keeps your organs (brain, heart muscles, etc.) functioning.
Typically, family physicians simply test a patient's TSH (thyroid-stimulating hormone) and T4 (thyroxine) levels in order to determine whether a thyroid condition exists. If the patient's levels are within the normal range, then the patient is told, "it's not your thyroid." But that's not always the full picture!
You may already know that hormones work like thermostats: when one level is activated, the other shuts off, and vice versa. Here's how your thyroid hormones work: The hypothalamus (a tiny gland located in the brain) releases a substance called thyrotroptin-releasing hormone (TRH), which triggers the pituitary gland to release the thyroid-stimulating hormone (TSH). TSH then triggers your thyroid gland to produce two hormones: triiodothyronine (T3) and thyroxine (T4). The T4 and T3 hormones circulate through your bloodstream "bound" to proteins, although a small percentage is considered "free," or unbound. Some T4 gets converted to T3 as it moves through multiple tissues and organs (notably the liver, brain, and muscle). Some T4 and T3 are separated from their protein carriers during these processes, becoming "free" again to exert a metabolic effect on the body. So what does this mean?
Thyroid hormone problems are complex. If you or someone you know suspects a thyroid issue, or simply wants to rule one out, it is important to consult with a clinician who is experienced in thyroid hormone dysfunction. Blood tests should be ordered to put together the clearest picture of how your thyroid hormones are working -- or not. For example, the "Total T4" test can tell your medical practitioner how much T4 your thyroid is producing, while the "Free T3" test helps to show how much is "bio-available" for the cells and tissues of your body.
In the case of subclinical hypothyroidism, the TSH blood test levels are typically normal or just slightly elevated while the T4 and T3 levels appear in the low to normal range -- in addition to the patient experiencing classic (though mild) symptoms of hypothyroidism. Even in this low-normal range, your thyroid may still be low-functioning (in the 10th percentile), creating symptoms that can significantly impact your quality of life. Every organ in your body relies on a healthy thyroid!
Our approach is to order blood tests that reveal the full picture of how your thyroid hormones are functioning, typically: TSH, Free T3, Free T4, TPO (Thyroid Peroxidase Antibody), TGA (Thyroglobulin Antibody), and Reverse T3. We understand the subtle signs of an imbalance, and carefully treat patients for subclinical hypothyroidism when symptoms are present. Our approach is to optimize your thyroid levels to the upper 1/3rd of the healthiest range, allowing you to feel better, have more energy, think more clearly, and lose weight more easily.
For more information on thyroid health and Thyroid Awareness Month, visit the American Thyroid Association at www.thyroid.org.