What Is A Tsh Test
Thyroid testsBlood tests to measure thyroid hormones are readily available and widely used. Not all thyroid tests are useful in all situations.
TSH TestThe best way to initially test thyroid function is to measure the TSH level in a blood sample. Changes in TSH can serve as an “early warning system” often occurring before the actual level of thyroid hormones in the body becomes too high or too low.
A high TSH level indicates that the thyroid gland is not making enough thyroid hormone . On the other hand, a low TSH level usually indicates that the thyroid is producing too much thyroid hormone . Occasionally, a low TSH may result from an abnormality in the pituitary gland, which prevents it from making enough TSH to stimulate the thyroid . In most healthy individuals, a normal TSH value means that the thyroid is functioning properly.
What Causes Congenital Hypothyroidism
SPAN: The most common cause of congenital hypothyroidism is failure of the thyroid gland to grow before birth. Sometimes the gland is present but doesn’t make the thyroid hormones. Other times the thyroid gland is located in an abnormal place in the neck. This makes it work less well. Or it can be caused by treatment of a thyroid problem while you are pregnant. If your diet is low in iodine, your child will also have low thyroid hormone levels at birth.
What Does Low Tsh Mean And What Are The Causes
Keep in mind that the pituitary gland plays a role in the production of eight hormones, including the TSH and thyroid hormones .
When a patient has low levels of TSH, it indicates that a patient has a health problem. The common causes are:
Hyperthyroidism is a medical condition wherein a patient will have high levels of thyroid hormones and a low TSH level.
When a patient has hyperthyroidism or Graves diseases, he will have an overactive thyroid wherein there is an increase in the levels of thyroid hormones. Because TSH is responsible for triggering the release of these thyroid hormones, the bodys natural response is to lower the TSH levels.
- Problem with the Pituitary Gland
In cases of Hashimoto thyroiditis or hypothyroidism, the patients thyroid hormones are low, thus, there should be an increase in TSH levels.
When both the thyroid hormones and TSH levels are low, it indicates that the patients pituitary gland is either weak or damaged because of a disease, head injury, or tumor.
It is crucial to seek medical attention if you have hypothyroidism and low TSH levels. Your doctor will order additional blood tests or brain scans to detect the underlying cause of the problem.
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Taking A T3 Only Medication
If you are taking a T3 only medication, it will often result in a drop in your T4 level.
T3 only medications include Cytomel and liothyroinine.
Why? It makes sense if you think about it.
Like we learned earlier, T4 acts as the storage reservoir for T3 in the body.
If you are taking a T3 only medication, then your need for that reserve of T4 decreases because you have bypassed the conversion process. This therefore results in less T4 production by the thyroid gland.
Taking a T3 only medication will typically cause the free T4 level to decrease, the TSH level to decrease, the reverse T3 level to decrease, and the total T3 and free T3 levels to increase.
This can also happen to a lesser extent if you are taking a natural dessicated thyroid such as Armour Thyroid, NP Thyroid, or Nature-throid. That is because these medications contain about 20% T3 and about 80% T4.
The drop in T4 level in this case is expected and what you want. It is not a sign of inadequate thyroid levels like it is in the other situations.
What Tsh Level Requires Treatment
The American Thyroid Association recommends that patients older than 65, should be treated for hyperthyroidism if TSH levels are below 0.1 mIU/L. Patients younger than 65 are treated if they are post-menopausal women, have coexisting conditions such as heart disease or osteoporosis, or symptoms of hyperthyroidism.
Subclinical hyperthyroidism with TSH levels between 0.1 to 0.4 mIU/L with normal T3 and T4 levels may be just monitored if the patient is below 65 and has no symptoms. Patients above 65 or those below 65 with comorbidities or symptoms of hyperthyroidism may be treated depending on their condition.
Doctors usually start treatment for hypothyroidism if the TSH level remains persistently elevated above 10.0 mIU/L even if T4 is normal and the patient has no symptoms. Thyroid levels are usually periodically monitored and maintained optimally with appropriate dosage changes.
Subclinical hypothyroidism, which means TSH levels of 5.0 to 10.0 mIU/L and normal T4, may require treatment if the individual has a positive thyroid antibodies test, experiences symptoms, or is at high risk for developing hypothyroidism.
If you have questions about TSH levels, ask your doctor to explain what your TSH level means.
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How The Test Is Performed:
Blood is drawn from a vein on the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic, and an elastic band is placed around the upper arm to apply pressure and restrict blood flow through the vein. This causes veins below the band to swell with blood.
A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. During the procedure, the band is removed to restore circulation. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding. For an infant or young child, the area is cleansed with antiseptic and punctured with a sharp needle or a lancet. The blood may be collected in a pipette , on a slide, onto a test strip, or into a small container. Cotton or a bandage may be applied to the puncture site if there is any continued bleeding.
What Is The Reason For High Tsh Levels
High levels typically indicates an underactive thyroid gland, which produces too little thyroid hormone. This is known medically as hypothyroidism.
Common causes of hypothyroidism include an autoimmune disease , radiation treatment, or surgical removal of the thyroid gland.
Replacing thyroid hormone and altering your diet are crucial for the safe and effective treatment of an underactive thyroid.
Summary: High TSH levels for the average adult are 4.2 mIU/L and over. This reading typically indicates an underactive thyroid.
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The Normal Tsh Levels In Women By Age: Table
TSH what is it? The real causes of ill health can determine the results of laboratory tests for hormones, which can clarify a lot a qualified physician, including the increased thyrotropic hormone TSH. Especially important normal TSH in women.
Medical statistics indicate that the female is much more common pathology of the thyroid gland and elevated TSH than in the male.
The norm are the following indicators:
- TSH norm in women is 0.44.2 mu/l
- the males 0,44,0 mu-l.
Does Thyroxine Treatment Have Side Effects
No good-quality research is available on the side effects of treating subclinical hypothyroidism with thyroxine, but it’s generally considered to be a well-tolerated drug. Because the body usually produces this hormone on its own, there are no problems if the dose is correct. If it’s too high though, side effects can’t be ruled out. Possible side effects include heart problems like or a racing heartbeat.
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What Is A Normal Tsh Level
When looking at a characteristic found in a large population of people, the results will follow a predictable distribution across a graph.
For example, if you graph the heights of everyone in the world, the results will range from as little as 21.5 inches to as tall as 97 inches with the average being about 68 inches. The majority of people in the world will be close to the average height. The further away from the average you go, the fewer people will be that height.
The result is what is commonly called a Bell Curve:
This is also how reference ranges for lab tests are determined.
However, a Bell Curve also assumes that all people included in the graph are equivalent – meaning none are on medication, have different diets, genetic history, etc. which could affect the results.
ZRT is a well-known national laboratory. Their website explains it like this:
Reference ranges do not always reflect a normal healthy population free of medications. Most laboratories establish their reference ranges from a large population of people where detailed information on health status, stage of life , and medications and hormones used is unknown, and therefore not taken into account. Couple this with differences in lifestyles, physiology, dietary habits, and genetic heredity, and its even more difficult to define, let alone find, a normal population.
So instead of a normal range of TSH ranging from about 0.4-5.0 which it is for most labs, it should instead be about 0.4-2.0.
What Do The Results Mean
High TSH levels can mean your thyroid is not making enough thyroid hormones, a condition called hypothyroidism. Low TSH levels can mean your thyroid is making too much of the hormones, a condition called hyperthyroidism. A TSH test does not explain why TSH levels are too high or too low. If your test results are abnormal, your health care provider will probably order additional tests to determine the cause of your thyroid problem. These tests may include:
- T4 thyroid hormone tests
Learn more about laboratory tests, reference ranges, and understanding results.
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When Is Treatment Needed
Treatment is needed when your thyroid levels are too high or too low, ranging outside the optimal levels. Normal TSH levels are typically considered 0.5-5.0 mIU/L. We prefer the upper limit to be 2.5 mIU/L.
Thyroid hormone replacement using levothyroxine is the most common treatment for an underactive thyroid . Usually, thyroid medications like levothyroxine are not our first response to treating thyroid dysfunction.
Radioactive iodine, antithyroid agents, and beta-blockers are the most common treatments for an overactive thyroid.
There are many different root causes of thyroid conditions. The best treatment for either hypothyroidism or hyperthyroidism is addressing your unique root cause, such as stress, leaky gut syndrome, toxin exposure, nutrient deficiencies, inflammatory diet, or thyroid cancer.
Here at PrimeHealth, we do just that create individual, integrative treatments that impact the root cause of your thyroid levels.
How To Raise Your T4
Fortunately, raising your T4 level is usually straight-forward.
Reversing what is causing your low T4 is the key to successful treatment.
You will either want to increase the thyroid hormone your body produces itself, or you will need to supplement what your body produces with a thyroid hormone medication.
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What Are Thyroid Hormones
Thyroid hormones are secreted by the thyroid gland using iodine, a mineral that is present in many foods and is abundant in seafood. The thyroid gland is a butterfly-shaped endocrine gland located at the base of the front of the neck. Endocrine glands are a network of organs that produce and release various hormones necessary for the normal functioning of the body.
Thyroid hormones regulate the metabolic rate of the body and thus play a major role in the proper functioning of every organ in the body. Thyroid hormones are essential for normal brain and physical development in infants. Thyroid hormones regulate body temperature and help maintain the normal function of all organs including the brain, heart, and muscles.
Thyroid hormones are found in two forms in the body:
- Thyroxine : Thyroxine constitutes approximately 95% of thyroid hormone circulating in the blood.
- Triiodothyronine : T3 accounts for the balance of 5% of thyroid hormone and is formed by the removal of one atom of iodine from T4, which is mostly done in the liver or kidney.
Only a minuscule percentage of thyroid hormones are in a free form that can enter cells and activate metabolism. More than 99.95% of T4 and 99.5% of T3 are bound to proteins in the blood. The binding proteins act as a storage system for the thyroid hormones, regulating the availability of free T4 and T3 for metabolic function.
Inflammation Of The Thyroid Gland
Hypothyroidism often results from previous or currently ongoing inflammation of the thyroid gland, which leaves a large percentage of the cells of the thyroid damaged and incapable of producing sufficient hormone.
The most common cause of thyroid gland failure is called autoimmune thyroiditis , a form of thyroid inflammation caused by the persons own immune system.
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In People With Thyroid Disease
In people being treated for hypothyroidism, a low TSH level may mean:
- Overmedication with thyroid hormone replacement
- Interactions that cause increased absorption or activity despite an optimal dose of medication
- Central hypothyroidism
In people being treated for hyperthyroidism, a low TSH level usually means that further treatment is needed to reduce thyroid hormone levels.
It could also mean that a person must continue to be monitored to make sure thyroid hormone levels return to normal. This is often the case for people who have temporary thyroiditis related to pregnancy or chemotherapy treatment.
Treatment may be more aggressive than needed
Medication may be absorbing too much
Potential Complications Of Hypothyroidism
Left untreated, the symptoms of hypothyroidism will usually progress. That can lead to complications including birth defects, infertility, elevated bad cholesterol, and mental health problems. Rarely, complications from untreated hypothyroidism can result in severe life-threatening depression, heart failure, or a type of coma called myxedema coma.
Additionally, because the body is expecting a certain amount of thyroid hormone, the pituitary will make additional thyroid stimulating hormone as a way to prompt the thyroid to produce more hormone . This extra work at signaling the thyroid gland to keep producing T4 may cause the thyroid gland to become enlarged, leading to the formation of a goiter .
What Is The Takeaway
One potential flaw in the study is the fact that hypothyroidism was defined as a TSH > 4.6. There are some clinicians who believe that the range for TSH is far to broad and that TSH should be within a tighter window such as 1.5, 2.0, or 2.5 as the upper cut-off point. There is little evidence to support this claim for every single human being who has Hashimotoâs or hypothyroidism.
Sure, some people just feel better with a TSH that is in these lower ranges but some people also feel great with higher TSH levels. As with everything in functional medicine, this is an individualized question which shouldnât be set in stone.
Additionally, as pointed out above, the patients who did have TSH levels above 4.6 after the 6 year follow-up had normal thyroid function despite the higher TSH levels.
Once weâve dealt with the most significant causes of Hashimotoâs thyroiditis including gut health, infections such as Epstein-Barr Virus, food sensitivities like gluten, vitamin D deficiency, selenium deficiency, stress, and childhood adversity, you can be confident that your immune system will continue to heal and stay in balance.
Levothyroxine Dosage Chart And Comparison Table
So, what if your Doctor isn’t willing to change medications or you really like being on Levothyroxine?
Then make sure you are on the right dose!
Your dose should be based off of the 3 step system I outlined above: Lab tests, symptoms, and your metabolism.
You can get to this dose by starting out with a low dose and then slowly increasing your dose and monitoring each of the steps.
From there you can check your lab tests every 6-8 weeks to follow your TSH, free T3, free t4 and reverse T3.
Dosing varies quite a bit based on the person but a typical dose may range between 25mcg and 250mcg of Levothyroxine or Synthroid per day.
If you have continued to increase your dose beyond 150mcg and haven’t noticed ANY improvement in your symptoms then that may be a sign to consider switching medications.
If your Doctor still isn’t willing to trial NDT or T3 containing medications then you can also try other forms of T4 with fewer fillers like Tirosint and continue increasing your dose slowly over time.
If you are switching from T4 to another medication this comparison chart may be helpful:
This chart isn’t perfect but it is a good starting place.
I find that the conversion from T4 to NDT or natural desiccated thyroid to be too low .
In my experience, 2 grains is closer to 100mcg of T4 than 1 grain, but it is important to start out slowly if you are switching medications because T3 can be VERY stimulating to some people.
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Normal Thyroid Levels: Typical Numbers & How Testing Works
Your thyroid gland is an essential part of your endocrine system that secretes hormones that regulate metabolism, heart function, digestion, muscles, brain development, and bone health.
In this article, well talk about typical thyroid hormone levels, which tests are important, and what to do if you have hypothyroidism.
What Is A Low Thyroid Number
A low thyroid number is when blood test results indicate your thyroid is not functioning properly. Low levels of the thyroid hormone in your blood will result in abnormal test results. There is treatment available for this condition.
The Thyroid Gland
The thyroid gland is located in your neck. It secretes thyroid hormones T3 and T4. These hormones help regulate your metabolism. The pituitary gland, located at the base of your brain, produces thyroid-stimulating hormones that tell your thyroid gland to produce T3 and T4.
Normal TSH levels are 0.4 to 4.0 mIU/L, according to MedlinePlus. Normal T3 levels are 100 to 200 ng/dL. Normal T4 levels are 4.5 to 11.2 mcg/dL.
Tests for thyroid function are done with blood draws. There is a test for the TSH hormone and one for the T3 and T4 hormones.
If your blood test shows low TSH levels, you may have a common condition called hyperthyroidism, which is when your thyroid gland produces too much T3 and T4. Low levels of T3 and/or T4, however, can indicate a condition called hypothyroidism.
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