Tsh 87

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[Last updated 29th December, 2018]

TSH is a hormone that controls thyroid gland activity.

It’s typically used as a marker of thyroid health, but what are normal TSH levels?

This article explores what your levels should be and how it relates to hypothyroidism.

Note that each section in this article has a ‘summary’ box (like this one) to save time. Below this box is a contents menu to help you navigate directly to a particular section.

Contents

What is TSH?

What is TSH?TSH is a hormone that controls thyroid function. It stands for Thyroid Stimulating Hormone.

It is actually produced by the brain’s pituitary gland, but stimulates production of the hormones triiodothyronine (T3) and thyroxine (T4) in the thyroid gland.

The amount and balance of these hormones affects almost every physiological process in the body, particular your body’s metabolism (1).

Summary: TSH is a pituitary hormone that stimulates or inhibits the production of thyroid hormones from the thyroid gland.

What Makes TSH Fluctuate?

The release of TSH is first stimulated by a hormone called TRH.

Once the thyroid stimulating hormone makes its way to your thyroid, levels are largely dictated by the amount of T3 and T4 in your blood.

When T3 and T4 levels are low, the body produces more TSH to stimulate the thyroid. But when T3 and T4 levels are high, the body produces less (2).

 

TSH cycle

Image source. Click to enlarge.

 

Several other factors can also influence TSH levels:

  • Inflammation of the thyroid gland
  • Genetics
  • Deficiency or excess of iodine in the diet
  • Poisonous substances and radiation exposure
  • Pregnancy
  • Certain medications- antidepressants, cholesterol lowering drugs, chemotherapy drugs, steroids
  • Thyroid cancer

Summary: Current levels of thyroid hormone in the blood significantly dictates your levels, although there are other factors that influence it too.

Hypothyroidism: What is TSH Level?

Due to the symbiotic nature they have with thyroid hormones, TSH levels in the blood can theoretically be a good marker of thyroid health.

This TSH levels chart presents a simplified version of what different readings can indicate.

TSH LevelsT3 and T4 LevelsDisease Condition
HighHighTumor of pituitary gland
LowLowSecondary hypothyroidism
LowHighGrave’s disease
HighLowHashimoto’s disease

Those with Graves’ disease (an overactive thyroid) have high low TSH and subsequent high thyroid hormone levels. Hashimoto’s disease (underactive thyroid) is the opposite.

Summary: Low TSH typically indicates excessive thyroid hormone levels, while high TSH indicates thyroid hormone deficiency.

Normal TSH levels

Normal TSH levelsWhat should your TSH level be?

Normal TSH levels for the average adult range from 0.4 ‑ 4.0 mIU/L (milli-international units per liter) (3).

However, many organizations agree that a reading of 2.5 or less is truly ideal for normal thyroid levels, with anything 2.5 – 4.0 mIU/L considered “at risk”.

For those on thyroxine, the ideal TSH normal range is between 0.5 to 2.5 mU/L.

The reference ranges alter slightly as we grow older and if you are pregnant:

TSH Normal Range By Age:

For premature birth (28‑36 weeks)

For children

  • Birth to 4 days: 1‑39 mIU/L
  • 2‑20 weeks: 1.7‑9.1 mIU/L
  • 21 weeks to 20 years: 0.7‑64 mIU/L

For adults

  • 21‑54 years: 0.4‑4.2 mIU/L
  • 55‑87 years: 0.5‑8.9 mIU/L

During pregnancy

  • First trimester: 0.3‑4.5 mIU/L
  • Second trimester: 0.3‑4.6 mIU/L
  • Third trimester: 0.8‑5.2 mIU/L

Small variations in results can occur depending on the laboratory and its methods used, as well as the time of day your blood was taken.

Summary: Normal levels range from 0.4 ‑ 4.0 mIU/L for the average adult.

High TSH Levels

A level reading above 4.0 mIU/L is considered high (elevated).

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.

High TSH levels

Common causes of hypothyroidism include an autoimmune disease (known as Hashimoto’s 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.

Low TSH levels

normal TSH levelsA reading below 0.4 mIU/L is considered low.

What does it mean when your TSH is low?

Low levels typically indicates an overractive thyroid gland, which produces too much thyroid hormone. This is known medically as hyperthyroidism.

It can be caused by an autoimmune disease (known as Graves’ disease), goiter, excessive iodine in the body, or an overdose of synthetic thyroid hormone.

Initial hyperthyroidism treatment can involve anti‑thyroid medications and radioactive iodine to slow down thyroid hormone production. Most respond well to hyperthyroidism medications and are treated successfully.

Summary: Low TSH levels for the average adult are less than 0.2 mIU/L. This reading typically indicates an overractive thyroid.

The Problem With Solely Relying on TSH Tests

normal TSH levelsTSH is the most well-studied marker for judging thyroid health and function.

It has been the gold standard test for decades, and is considered the most sensitive and accurate indicator by most endocrinologists and other doctors.

However, more recent research indicates our systematic reliance on it is missing the mark. This leaves a lot of hypothyroid cases either misdiagnosed or undiagnosed.

Some clinical studies have found that both T3 and TSH levels can decline at the same time, particularly in obese individuals that lose weight (4, 5).

That means T3 levels can be low, yet TSH will remain in the normal range.

Certain medications, such as metformin, are also known to independently lower TSH levels in diabetics and PCOS patients with thyroid issues (6).

These variables are just the tip of the iceberg, but highlight why TSH is not completely reliable on its own. Considering the pituitary gland (which produces TSH) is unique in its function, it makes sense that some metabolic processes and outside stressors can influence TSH activity.

This is something to discuss with your doctor if your readings are high-normal, yet you still feel seriously unwell.

Summary: Several external stressors are known to influence TSH levels, independently of thyroid hormone levels. This means TSH on it’s own is not always a reliable indicator of thyroid health.

TSH Tests at Home

It’s not uncommon for doctors to skip over TSH testing if they do not believe there is a thyroid issue.

Fortunately, there is reliable way to measure thyroid stimulating hormones yourself with a home-testing kit. It’s FDA approved to be as accurate as a blood draw test, and results are sent direct to you by email or phone call.
TSH test
Click here to take a look on Amazon (aff link).

Have a read of the interesting reviews, as there’s the occasional comment that results are slow to get back.

Additional Tests For Thyroid Health

Given the potential inaccuracies with TSH on its own, comprehensive screening of thyroid health should ideally include these 6 tests:

  • TSH
  • Free T3
  • Free T4
  • Reverse T3
  • Thyroid Peroxidase Antibodies
  • Thyroglobulin Antibodies

Your doctor should be aware of these tests.

(Know that I cannot give personal medical advice. Please speak with your doctor.)

About Joe Leech, Dietitian (MSc Nutrition & Dietetics)

Joe Leech is a university-qualified dietitian from Australia.

He graduated with a Bachelor's degree in exercise science, followed by a Master's degree in Nutrition and Dietetics in 2011.

Learn more about him on the About page. 

Sours: https://www.dietvsdisease.org/normal-tsh-levels/

Hypothyroidism in the elderly: diagnosis and management

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Sours: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3340110/
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Thyroid function tests are a series of measurements of different aspects of thyroid hormone presence in the blood stream.

A common panel of thyroid function tests consists of:


T4 (Thyroxine)

This is a measure of all of the active form of thyroid hormone in the blood. 95% of the total is bound to plasma proteins, particularly thyroid binding globulin (TBG). 

It is elevated in hyperthyroidism and depressed in hypothyroidism. It is usually slightly elevated during pregnancy because of increased levels of TBG.


T3 (Triiodothyronine, T3-RIA) by radioimmunoassay

T3 is metabolically a more active form of thyroid hormone than T4, but its' effects are of shorter duration.

It is elevated in hyperthyroidism and depressed in hypothyroidism. 


T3 Uptake

This is a measure of the unbound throxine binding globulins in the blood (unsaturated with thyroid hormone). The less thyroid hormone that is present, the more unsaturated TBG is present.

This is an indirect measure of thyroid hormone levels. It has nothing to do with T3, despite the name.


Free T3 (FT3, Free Triiodothyronine T3)

Free T3 is one of the determinations used to measure thyroid function. T3 is mostly bound to plasma proteins, and the remainder (FT3) is unbound.

It is elevated in hyperthyroidism and depressed in hypothyroidism.


Free T4 (FT4, Free Thyroxin)

Most thyroid hormone is bound to plasma proteins. Some (about 5%) is not bound ("free") and available to serve a metabolic role. Free T4 is the most accurate assessment of thyroid hormone levels, because it avoids changes in plasma protein binding capabilities. 

It is elevated in hyperthyroidism and depressed in hypothyroidism.


FTI (Free Thyroxine Index, FTI, T7)

The FTI is obtained by multiplying the (Total T4) times (T3 Uptake) to obtain an index.

The FTI is considered a more reliable indicator of thyroid status in the presence of abnormalities in plasma protein binding.

It is elevated in hyperthyroidism and depressed in hypothyroidism.


TSH (Thyroid Stimulating Hormone)

Because of the normal feed-back loop, TSH rises whenever the thyroid gland fails to produce sufficient thyroid hormone. 

For the same reason, whenever there is too much thyroid hormone present in the serum, the brain responds by lowering the TSH.

It is elevated in hyperthyroidism and depressed in hypothyroidism.

Sours: https://www.glowm.com/lab-text/item/87
Thyroid Gland, Hormones and Thyroid Problems, Animation

The proportion of people with normal TSH and low or high FT4 levels, who would have been missed with a one-step approach were calculated. Various characteristics of participants, including gender, age, smoking status, height, weight, body mass index (BMI), blood pressure, alcohol use, use of thyroid-affecting medications, and menopausal status, were used to determine whether these can be used to calculate a score to predict risk of thyroid hormone abnormalities.

The average age of participants was 51 years (range, 16.5-97) and 55% were women. This population was considered iodine-sufficient and mostly white. Of 4,471 adults, 35 (0.8%) had overt hypothyroidism, 86 (1.9%) subclinical hypothyroidism, 23 (0.5%) overt hyperthyroidism, and 170 (0.5%) subclinical hyperthyroidism. A total of 82 (1.8%) had normal TSH and low FT4 levels, and 87 (1.9%) had normal TSH and high FT4 levels. The FT4 levels were very close to the normal range in a majority (144 participants, 85%) of 169 participants with normal TSH but low or high FT4 levels.

Significant risk factors for hypothyroidism included being female, age 50 to 75 years, age > 75 years, and BMI ≥ 30kg/m2. The only significant risk factor for hyperthyroidism was smoking status. However, both sets of risk factors did not have good level of prediction of thyroid hormone abnormalities.

WHAT ARE THE IMPLICATIONS OF THIS STUDY?

Only 7% of adults needed both TSH and FT4 to be checked to determine whether their thyroid hormone levels were abnormal. Even in those with low or high FT4 but normal TSH, FT4 levels were very close to normal range, and unlikely to have caused any clinical symptoms that warranted treatment.

Since the majority of patients did not need FT4 levels to make the diagnosis of thyroid hormone abnormalities, it would be most cost-effective to have a two-step approach in assessing thyroid dysfunction, where TSH is measured and FT4 is measured only if TSH is abnormal. There are rare cases of hypothyroidism from pituitary problem, where both TSH and FT4 levels are low, but these patients typically have other clinical signs that would suggest such diagnosis.

— Sun Y. Lee, MD

Sours: https://www.thyroid.org/patient-thyroid-information/ct-for-patients/december-2018/vol-11-issue-12-p-7-8/

87 tsh

Serum TSH, T(4), and thyroid antibodies in the United States population (1988 to 1994): National Health and Nutrition Examination Survey (NHANES III)

NHANES III measured serum TSH, total serum T(4), antithyroperoxidase (TPOAb), and antithyroglobulin (TgAb) antibodies from a sample of 17,353 people aged > or =12 yr representing the geographic and ethnic distribution of the U.S. population. These data provide a reference for other studies of these analytes in the U.S. For the 16,533 people who did not report thyroid disease, goiter, or taking thyroid medications (disease-free population), we determined mean concentrations of TSH, T(4), TgAb, and TPOAb. A reference population of 13,344 people was selected from the disease-free population by excluding, in addition, those who were pregnant, taking androgens or estrogens, who had thyroid antibodies, or biochemical hypothyroidism or hyperthyroidism. The influence of demographics on TSH, T(4), and antibodies was examined. Hypothyroidism was found in 4.6% of the U.S. population (0.3% clinical and 4.3% subclinical) and hyperthyroidism in 1.3% (0.5% clinical and 0.7% subclinical). (Subclinical hypothyroidism is used in this paper to mean mild hypothyroidism, the term now preferred by the American Thyroid Association for the laboratory findings described.) For the disease-free population, mean serum TSH was 1.50 (95% confidence interval, 1.46-1.54) mIU/liter, was higher in females than males, and higher in white non-Hispanics (whites) [1.57 (1.52-1.62) mIU/liter] than black non-Hispanics (blacks) [1.18 (1.14-1.21) mIU/liter] (P < 0.001) or Mexican Americans [1.43 (1.40-1.46) mIU/liter] (P < 0.001). TgAb were positive in 10.4 +/- 0.5% and TPOAb, in 11.3 +/- 0.4%; positive antibodies were more prevalent in women than men, increased with age, and TPOAb were less prevalent in blacks (4.5 +/- 0.3%) than in whites (12.3 +/- 0.5%) (P < 0.001). TPOAb were significantly associated with hypo or hyperthyroidism, but TgAb were not. Using the reference population, geometric mean TSH was 1.40 +/- 0.02 mIU/liter and increased with age, and was significantly lower in blacks (1.18 +/- 0.02 mIU/liter) than whites (1.45 +/- 0.02 mIU/liter) (P < 0.001) and Mexican Americans (1.37 +/- 0.02 mIU/liter) (P < 0.001). Arithmetic mean total T(4) was 112.3 +/- 0.7 nmol/liter in the disease-free population and was consistently higher among Mexican Americans in all populations. In the reference population, mean total T(4) in Mexican Americans was (116.3 +/- 0.7 nmol/liter), significantly higher than whites (110.0 +/- 0.8 nmol/liter) or blacks (109.4 +/- 0.8 nmol/liter) (P < 0.0001). The difference persisted in all age groups. In summary, TSH and the prevalence of antithyroid antibodies are greater in females, increase with age, and are greater in whites and Mexican Americans than in blacks. TgAb alone in the absence of TPOAb is not significantly associated with thyroid disease. The lower prevalence of thyroid antibodies and lower TSH concentrations in blacks need more research to relate these findings to clinical status. A large proportion of the U.S. population unknowingly have laboratory evidence of thyroid disease, which supports the usefulness of screening for early detection.

Sours: https://pubmed.ncbi.nlm.nih.gov/11836274/
Hypothalamic Pituitary Thyroid Axis (regulation, TRH, TSH, thyroid hormones T3 and T4)

I rubbed my pussy with my free hand. Then I felt something more gently enter my anus. My husband whispered in my ear that he always dreamed of shoving a banana up my ass.

Now discussing:

Lera did not hear them, they also did not pay attention to her, communicating more with Veronica and Marina. Lera said that she had to go to the hotel. When she moved a little away from the company, she heard laughter.



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