Thyroid Function Test: Everything you need to know
Tests for thyroid function diagnose and monitor thyroid disorders. The test can also check the effectiveness of thyroid hormone replacement therapy.
Typically, these disorders can cause excess weight gain and symptoms such as tiredness, heart palpitations, and an intolerance of cold temperatures.
Learn more about why you might need this thyroid function test and what it can tell you about your body’s health status.
What are thyroid hormones?
The thyroid is a small, butterfly-shaped gland on the front of the neck that produces thyroid hormones and regulates the body’s metabolism.
Various thyroid hormones comprise two main thyroid hormones: thyroxine (T4) and triiodothyronine (T3). The pituitary gland produces thyroid-stimulating hormone (TSH), which helps regulate thyroid hormone production.
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Hypothyroidism
Hypothyroidism is the condition when the thyroid gland does not produce enough hormones. It can lead to fatigue, weight gain, depression, and dry skin. If you think you might have hypothyroidism, see your doctor for a diagnosis. Your doctor will do a physical exam and check your thyroid levels using a simple blood test. They may also order more tests to rule out other causes of your symptoms.
Hyperthyroidism
Hyperthyroidism is an overactive thyroid gland that releases too much hormone into the bloodstream. The most common symptom of hyperthyroidism is an abnormally fast heart rate, but other potential signs include anxiety, nervousness, trembling hands or feet, and problems sleeping. Thyroid function tests diagnose these conditions by measuring the T3, T4, and TSH. These levels change depending on what type of disorder is present.
Types of thyroid function test
The thyroid function test measures the levels of three different hormones:
- Thyroxine (T4)
- Triiodothyronine (T3)
- Thyroid-stimulating hormone (TSH)
Triiodothyronine (T3)
The total T3 test measures how much thyroxine exists and its conversion into triiodothyronine (T3). The amount of T3 produced by the body is crucial for many bodily functions, including muscle contraction, heart rate, and metabolism.
Thyroxine (T4)
T4 is the form of thyroid hormone circulating in the blood. The thyroxine (T4) test measures the amount of thyroxine in your blood. It determines a thyroid problem and checks for hypothyroidism.
Thyroid-stimulating hormone (TSH)
The TSH test measures how much thyroid hormone is present in the body. Hypothyroidism and subclinical hypothyroidism occur when the thyroid gland does not produce enough thyroid hormones.
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How To Prepare For The Test?
If your doctor orders a thyroid function test, you may wonder how to prepare. The test requires no special preparation.
You may need to fast for several hours before other blood tests if your health care provider orders them. If there are any special instructions you should follow, your health care provider will let you know.
Diagnosis using the results from this test
The results can help to identify whether a person has hypothyroidism or hyperthyroidism.
- Low levels of T3 and T4 may show hypothyroidism.
- High levels of T3 and T4characterize hyperthyroidism.
- The imbalance of T3 and T4 hormones lead to Graves’ disease.
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Managing Thyroid Function with the Best Diet & Supplements
The best way to manage your thyroid function with diet and supplements is through eating right, getting enough sleep, exercising daily, and taking thyroid-friendly supplements.
Eating Right: The first step in managing your thyroid with a diet is to eat foods rich in iodine—which helps keep the thyroid healthy and functioning well.
Foods rich in iodine include Fish (salmon, tuna, halibut), shellfish (lobster, crab), seafood (shrimp, calamari), Eggs, and Milk products.
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Getting enough sleep: It is vital to get enough sleep so that your body has time to rest while it repairs itself from all the work it does during the day.
If you are having trouble sleeping at night, try these tips:
a) Make sure your room is dark and quiet (no electronics)
b) Avoid caffeine after noon
c) Do not drink alcohol before bedtime
Exercising daily: keeps your metabolism healthy by preventing thyroxine and triiodothyronine overproduction and underproduction.
Taking thyroid-friendly supplements: You can also take supplements such as selenium sulfide (Se-Sulphide), which helps to regulate thyroid function.
We recommend taking this supplement daily as part of a balanced diet, as we do not recommend dietary supplements for people with heart disease or diabetes.
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