THYROID FUNCTION TEST
ALWAYS FEELING FATIGUED OR STRESSED?
There are currently about 25 million Americans diagnosed with some sort of thyroid disorder. Thyroid disorders tend to be more prominent in women, and the probability of a thyroid disorder occurring is four times more likely in women than in men.
The Thyroid is a butterfly shaped gland in the neck which makes T3, T4, and calcitonin (calcium regulating hormone), and can be affected by Reverse T3 levels. These regulate virtually every aspect of metabolism: body temperature, mood, sex hormones, energy levels, and even impact one’s appearance, from hair and nails to skin and waistline. Abnormalities lead to weight gain, fatigue, sensitivity to cold, muscle weakness, joint pain, pale/dry skin, and mood disorders.
SEE THE WHOLE PICTURE
Our test also includes a Reverse T3 test, which most thyroid tests do not include. Reverse T3, the inactive mirrored form of T3, inhibits T3 function. Measuring Reverse T3 levels is considered to be essential in the diagnosis and management of an underactive thyroid.
Patients with high levels of Reverse T3 tend to have lower than normal metabolism, constant weight gain without changing eating habits, crushing fatigue, increased sensitivity to cold, muscle weakness, joint or muscle pain, pale or dry skin, symptoms of hypothyroidism, chronic pain, and/or depression, anxiety and/or bipolar disorder.
NATURALLY PROMOTE PROPER FUNCTIONING
The body cannot fully achieve optimal thyroid functioning if lacking in key micronutrients. Any deficiencies can disrupt proper endocrine function. For this reason, it is recommended that the Thyroid Function test be paired with the Micronutrient test to give a more complete diagnostic picture.
With these results together, a custom program of natural micronutrient supplementation can target deficiencies that are leading to irregular thyroid functioning.
THYROID FUNCTION TEST: $150
**NO FASTING REQUIRED**
HOW DOES THE THYROID GLAND FUNCTION?
Thyroid hormones directly regulate every cell in our body as most basic functions like metabolism, emotions and thinking. We also test several proteins that affect thyroid function as well as antibodies to thyroid which can detect autoimmunity (when the immune system attacks healthy tissue) and your levels of cortisol, the stress hormone.
The major thyroid hormone secreted by the thyroid gland is thyroxine, also called T4 because it contains four iodine atoms. To exert its effects, T4 is converted to triiodothyronine (T3) by the removal of an iodine atom. This occurs mainly in the liver and in certain tissues where T3 acts, such as in the brain. The amount of T4 produced by the thyroid gland is controlled by another hormone, which is made in the pituitary gland located at the base of the brain, called thyroid stimulating hormone (abbreviated TSH). The amount of TSH that the pituitary sends into the blood stream depends on the amount of T4 that the pituitary sees. If the pituitary sees very little T4, then it produces more TSH to tell the thyroid gland to produce more T4. Once the T4 in the blood stream goes above a certain level, the pituitary’s production of TSH is shut off. In fact, the thyroid and pituitary act in many ways like a heater and a thermostat. When the heater is off and it becomes cold, the thermostat reads the temperature and turns on the heater. When the heat rises to an appropriate level, the thermostat senses this and turns off the heater. Thus, the thyroid and the pituitary, like a heater and thermostat, turn on and off.
T4 and T3 circulate almost entirely bound to specific transport proteins, and there are some situations which these proteins could change their level in the blood, producing also changes in the T4 and T3 levels (it happens frequently during pregnancy, women who take control birth pills, etc).
WHAT IS TESTED?
Free T3 (Free Triiodothyronine) – the more potent and biologically active thyroid hormone, T3 regulates growth and metabolism throughout the whole body.
Free T4 (Free Thyroxine) – considered a precursor hormone, T4 is converted to T3 as required by cells throughout the body; levels of T4 are generally much higher than T3.
Total T4 (Total Thyroxine) - Most T4 in the blood is bound to carrier proteins which make it biologically inactive. Total T4 includes unbound (free) T4 plus T4 that is bound to carrier proteins in the blood.
rT3 - Reverse T3 (Reverse Triiodothyronine) - As the name implies, Reverse T3 opposes the biological action of T3. It slows metabolism and renders T3 in the body biologically inactive. The rate of rT3 production relative to T3 will increase in times of stress (high cortisol) and in the presence of nutrient deficiencies, inflammation or certain medications.
Thyroid Stimulating Hormone (TSH) – produced by the pituitary gland, TSH tells the thyroid gland to increase or decrease production of T4 or conversion to T3 depending on the amounts circulating in the bloodstream via an efficient feedback system.
Anti-TG (Antibodies to Thyroglobulin) – a precursor to T4. If Anti-TG are present in significant amounts, this suggests an abnormal immune response against your own body, also called autoimmunity.
Anti-TPO (Antibodies to Thyroperoxidase) – is an enzyme that initiates the synthesis of T4. Antibodies to TPO indicate autoimmunity where the body is attacking normal proteins in the blood (in this case, TPO). People with anti-TPO have a higher chance of developing hypothyroidism that those who do not have antibodies to TPO.
Tg (Thyroglobulin) – The main function of Tg is to store iodine, which is a necessary nutrient for the production of thyroid hormones T3 and T4. This test is particularly useful when monitored over time versus a single measurement and can sometimes be a useful tumor marker in patients with previous thyroid cancer.
TBG (Thyroid Binding Globulin) – is a carrier protein for thyroid hormones so its role is to transport T4 and T3 through the bloodstream. The thyroid gland adjusts to changing levels of TBG in order to keep free T4 constant and it is particularly useful when thyroid (T4) levels do not necessarily correlate with clinical symptoms. TBG levels are largely affected by other hormones and many prescription drugs and is useful in diagnosing the reason behind abnormal thyroid hormone levels.