What level of TSH indicates hypothyroidism?

If you are experiencing symptoms suggestive of hypothyroidism, your doctor may order a blood test to measure your levels of thyroid-stimulating hormone (TSH). Normal TSH levels fall between 0.4 and 4.0 milliunits per liter (mU/L), according to the American Thyroid Association. If your level is higher than this, chances are you are hypothyroid (have an underactive thyroid).  To makes the matter more complicated, some physiologist such as Ray Peat (Ph.D.) suggests, that you are not healthy if your TSH is over 1!

 

What is TSH and TSH Test?

The abbreviation “TSH” refers to “Thyroid Stimulating Hormone.” This hormone is measured in the blood by a TSH test. Thyroid disease may be indicated by TSH levels that are either abnormally high or low.

A TSH test checks to see if your thyroid gland is working properly. The thyroid gland is a tiny gland at the front of the neck that looks like a butterfly. Your thyroid produces hormones that regulate how your body uses available energy.

Your heart is one of the many organs impacted by the hormones your thyroid produces. They regulate not only your weight but also your body temperature, the power of your muscles, and even your mood.

Many of your body’s activities will become less efficient if you do not have sufficient thyroid hormones in your blood. When you have too much, many of the functions in your body accelerate up.

Your pituitary gland, which is located in your brain, is responsible for controlling your thyroid. The production of Thyroid-Stimulating Hormone is handled by the pituitary gland. Your thyroid can determine how much thyroid hormone it needs to produce based on the levels of TSH.

What is the TSH test used for?

To emphasize again, a TSH test is utilized to determine how well your thyroid is functioning initially. It can determine whether you are hyperthyroid (excess thyroid hormone) or hypothyroidism (insufficient thyroid hormone). However, a TSH test cannot identify the root cause of a thyroid condition.

You’ll undergo routine TSH testing to monitor your thyroid hormone levels if you take prescription thyroid hormone medication due to hypothyroidism or remove your thyroid.

Why do I need TSH tests?

If you have symptoms that indicate either an excess of or a deficiency in thyroid hormone in your blood, you should have a TSH test.

Underactive thyroid is another name for the condition known as hypothyroidism, which is characterized by low levels of thyroid hormone. Your body’s functioning will slow down, and you will experience symptoms such as the following if you do not have enough thyroid hormone:

• Fatigue
• Weight gain
• Being extremely sensitive to cold causes discomfort in the joints and muscles
• Skin that is dry and hair that is thinning
• Heavy or irregular menstrual periods
• Depression
• Constipation

In contrast to hypothyroidism, an overactive thyroid is another name for hyperthyroidism, which refers to an excess of thyroid hormone in the body. When you have more thyroid hormones in your body than you need, your bodily processes accelerate, and you experience a variety of symptoms, including the following:

• Loss of weight, even though you might be consuming more than usual.
• A pulse that is either rapid or irregular
• Having feelings of agitation or anxiety
• Trouble sleeping, tiredness
• Weakness in the muscles, trembling hands
• Exhibiting sweating or a high degree of heat sensitivity
• Regular evacuations of the bowels (pooping a lot)
• Goiter (enlarged thyroid)

If you have strange bumps or lumps on your thyroid, such as those that could be thyroid cancer or thyroid nodules (growths on your thyroid that are not cancer), your doctor may recommend that you have a TSH test in addition to the other tests that are already being performed.

How does a TSH test work?

Blood will be drawn from a vein in your arm using a tiny needle. Following the insertion of the needle, a small amount of blood will be gathered in a test tube or vial. When the needle enters or exits, you can experience a slight sting. Usually, this takes less than two minutes.

Do I need to prepare for the test in any way?

For a TSH blood test, no extra preparations are required. If your doctor has requested additional blood tests, you might need to fast (not eat or drink anything) for a few hours before the test. Your doctor will inform you if there are any particular instructions to follow. Do not take thyroid medication before the test. Do it after your blood has been drawn.

Do the test’s dangers exist?

Having a blood test carries relatively little risk. Most symptoms pass fast. However, you can experience mild pain or bruise when the needle is inserted.

Things that can affect TSH test results

Several different things can change TSH levels. These things are essential to think about because lab results don’t tell the whole story about a person’s health. If a person’s symptoms aren’t considered in their treatment plan, it may not work.

Mistake in the lab

If TSH test results are unexpected, it is often best to do the test again. Errors can happen when blood is drawn, results are written down, or something goes wrong in the lab. Statistics show that there is always a chance of a mistake in the lab, so results should always be interpreted in light of symptoms and other clinical findings.

Antibodies

Antibodies are thought to make thyroid tests less accurate in about 1% of people. More than half of the people with these antibodies were misdiagnosed or given the wrong treatment because of this:

• Heterophile antibodies are common in people who have taken drugs made from animals or had antibody therapy. If there is a difference between your TSH levels and your free T4 levels or your TSH levels and how you feel, your doctor should know that the test isn’t proper.
• Thyroid antibodies can also change a person’s TSH level, even if they don’t have a thyroid condition. Again, a difference between the lab results and how you feel should make you wonder if the test isn’t accurate.
• Antibodies to ruthenium and streptavidin can also change the results of a TSH test.

Health and Lifestyle

Several other things can affect the results of a TSH test, such as:

The time of day the test is given

If you are tested after you haven’t eaten, like before you’ve had anything to eat for the day, your TSH levels may be higher than if you had just eaten.

Illness

A short-term or long-term illness can stress your endocrine system, which can change the results of a test.

Pregnancy

Even if you don’t have a thyroid disorder, your TSH levels may be lower than usual during pregnancy.

Medication

Some drugs used to treat heart disease and cancer can change how well they work. NSAIDs or nonsteroidal anti-inflammatory drugs can do the same thing.

Foods or supplements

Things that are high in iodine or made from kelp can mess up tests. Biotin supplements are the same.

Changes in sleep habits

A thyroid imbalance has been linked to not getting enough good sleep.

Drugs (narcotics)

Some street drugs such as amphetamine “Speed” or “Crystal Meth” can also influence your TSH and thyroid levels.

Interpreting TSH levels

It is easier to understand what a low TSH level and a high TSH level say about the function of your thyroid when you better understand when and why thyroid hormone is released (or not).

The TSH level is expressed as mU/L. This term refers to the number of milliunits included in one liter, with one milliunit equaling one-thousandth of a unit.

TSH levels should typically fall in the normal range of 0.4 mU/L to 4.0 mU/L.

However, this norm has some notable exceptions, just like most medical problems and examinations.

If your thyroid hormone levels are low, your pituitary gland will produce more TSH. This sends a signal to the thyroid, which causes it to increase production. When the substance is abundant, the pituitary gland produces less TSH.

The thyroid responds to this by slowing down its activity. This is why having a high TSH implies having poor thyroid function and vice versa.

The amount of T4 your pituitary gland tells your thyroid gland to make is shown by the TSH level in your blood. If your TSH levels are too high, it could mean you have hypothyroidism, which is when your thyroid doesn’t work as well as it should. This is because it means that your pituitary gland is making more TSH. Get your thyroid to make more thyroid hormone.

How do TSH levels change?

The value in the TSH appears to be counterintuitive. TSH, often known as thyroid hormone, might be unique for each individual. Your thyroid gland is responsible for regulating a wide variety of bodily functions.

If you suffer from thyroid disease, you may notice that the thyroid hormone levels in your body shift from time to time. These shifts are possible depending on how far along you are in your thyroid condition.

Alterations in your thyroid hormone levels can also be caused by other causes, such as changes in your hormone levels and medications, as well as significant weight gain or loss. In rare circumstances, the advancement of thyroid disease (such as a nodule) may be responsible for these changes. These changes in hormone levels might result in a wide array of symptoms.

Controversies over optimal TSH

TSH levels in a person are affected by several non-modifiable factors, which also determine what constitutes a “normal” result for that person. This covers differences that may be attributed to a person’s biological sex or age and shifts that can be attributed to the many seasons that occur throughout the year.

Several knowledgeable individuals have suggested that the maximum value for a normal TSH should be closer to 2.5 mU/L.

In addition, some medical professionals think older patients should have a TSH level that is higher than 4.0 mU/L or 5.0 mU/L. This is because TSH levels often rise with age.

By treating each patient as an individual, many professionals in the medical industry dodge the criticism surrounding this issue. For instance, a person with significant hypothyroidism symptoms at a TSH of 4.0 mU/L may fare better with a goal TSH of approximately 0.4 mU/L. This is because a lower TSH is associated with a better prognosis.

In contrast, a person with health concerns such as heart disease or osteoporosis may benefit from having a higher goal TSH, possibly around 5.0 mU/L or 6.0 mU/L. People with health risks tend to have higher thyroid-stimulating hormone (TSH) levels.

Raymond Peat (Ph.D.)

TSH levels are also affected by pregnancy. During the first three months, they are often a little low. But sometimes, thyroid disease happens when a woman is pregnant. If you get thyroid disease while pregnant, your doctor will keep an eye on it while you’re pregnant and after the baby is born.

In the first trimester of pregnancy, the TSH level should not be permitted to rise over 2.4 mU/L; in the second and third trimesters, it should not rise above 3.0 mU/L. This safeguards the well-being of the mother as well as the infant.

Differences in TSH levels in females and males

According to several studies, the normal range for TSH levels in female patients can range from 0.15 to 3.15 mU/l. These findings may help to explain why the TSH concentration in females is significantly higher than that in males, whose normal levels of TSH range from 0.6 to 4.0.

It has been recommended by medical professionals, in specific contexts, that adults over 60 should have an average TSH level greater than 5.0 . For instance, persons who suffer from hypothyroidism at a TSH level of at least 1.0 mg/L may experience an improvement in their condition.

Normal TSH levels in pregnancy

The levels of some thyroid hormones in the blood naturally rise when a woman is pregnant. This is very important for the brain and nervous system of the fetus.

At the same time, the blood level of TSH goes down. So, doctors use lower reference ranges when a woman is pregnant. The lower limit of the TSH range goes down by about 0.4 mU/l, and the upper limit goes down by about 0.5 mU/l.

During the second and third trimesters, the levels of TSH in the blood slowly rise, but they stay below average in women who are not pregnant.

TSH levels that are normal in children

TSH levels are highest when a baby is born and slowly decrease as a child grows up. So, TSH levels can be different between children. After the baby is born, doctors may say that a child has mild hypothyroidism if the TSH level is between 4.5 and 10 mU/l. Known Source.

From an older study with data from 512 healthy children, the following table shows the TSH levels of children by age:

When TSH alone isn’t enough

Most medical professionals utilize the TSH test during the diagnostic process to assess the level of thyroid function and select the most appropriate treatment option. However, there are situations in which knowing one’s TSH alone might not be adequate.

For instance, in addition to testing for TSH, a healthcare provider will typically test for free T4 if they suspect a patient’s pituitary gland or hypothalamus condition is causing thyroid malfunction.

It is also possible to examine a person’s free T4 levels if their TSH levels are normal but they are still exhibiting either hyperthyroidism or hypothyroidism.

In addition, TSH alone may not be sufficient to monitor hypothyroidism in pregnant women; T4 and free T4 are frequently advised.

Other thyroid function tests, such as T3, free T3, reverse T3, and thyroid antibody tests, might also be performed, depending on the specific circumstances of the patient’s case.

However, as some medications can impair thyroid function, you must tell the doctor what you’re taking. Start thyroid medication immediately if you have hypothyroidism symptoms or anti-thyroid antibodies. Your doctor should monitor your thyroid function with blood tests every six to 12 months if you’re not treated.

When people take NDT or synthetic T3, their TSH levels are typically “below the norm” when they feel their best. Medicines such as Cytomel (synthetic T3 only medication often used for weightloss), natural  thyroid hormones medications such as Armour Thyroid, WP Thyroid or NP Thyroid.  ALso some supplements might affect TSH VitaliThy (a type of Natural Desiccated Thyroid you can buy online) or Real Thyroid and other drugs that thyroid patients are recommended to take regularly. However, you will need to work closely with your doctor to get a prescription for these drugs.