TSH: what is it, values ​​and relationship with the thyroid

TSH is the acronym for "thyroid stimulating hormone," that is, the hormone produced by the pituitary gland. Its function is to regulate the production of hormones by the thyroid gland so when we talk about What is TSH? we refer to the parameter that allows us to control the thyroid, and that we explain below with everything detail.

What is TSH?

TSH is a hormone that directly influences thyroid activity . It is produced by the pituitary , which is a small gland present in the skull. When the human body is subjected to strong stress, whether psychological or physical, the hypothalamus, which is a part of the brain, produces TRH , which is the hormone that releases thyrotropin. This also occurs when there is a decrease in thyroid hormone levels.

TRH , in practice, acts on the anterior pituitary gland in order to induce it to increase the production of TSH which, once segregated, acts on the thyroid and is key to producing more thyroid hormones, until it returns to its normal value, from a molecule called thyroglobulin.

TSH and the thyroid

To understand the importance of the TSH is good to examine and know the thyroid more closely: the latter is a gland , whose shape resembles the figure of a butterfly, which is in front of the trachea, at the base of the neck on the front.

The hormones that produce the thyroid , triiodothyronine and thyroxine , spread throughout the body through the circulation. Blood ion and perform different tasks: contribute to the regulation of body temperature, cooperate to maintain the balance of the body, make it grow and produce heat (ie energy).

The TSH is produced according to a diurnal rhythm : mid-morning production is lower, while the peak occurs during the last hours of the afternoon. In summary, TSH is measured, through simple blood tests, to understand if the thyroid works well.

Maintaining control and monitoring of TSH values ​​is important to see if the thyroid is healthy and functioning as it should: this substance, in fact, regulates T3 and T4, namely triidothyronine and thyroxine, which are nothing more than the two thyroid hormones.

In principle, the values ​​of reference, and therefore normal TSH range from a minimum of 0.5 to a maximum of 4 mUI per liter, although it can be more or less significant variations according to the laboratory in which examine.

In pediatrics, normal TSH values ​​change according to age:

  • for children born at 28 - 36 weeks, and therefore premature, are established between 0.7 and 27 mlU per liter;
  • for children born a few days, they are established between 1 and 39 mlU per liter;
  • for children of between two and twenty weeks, between 1.7 and 9.1 mlU per liter are established;
  • for children over twenty weeks,
  • for adolescents and children up to 20 years of age, establish between 0.7 and 6.4 mlU per liter.

As for adults, on the other hand, the average values ​​depend to a large extent on age:

  • between 21 and 54 years of age are between 0.4 and 4.2 mlU per liter;
  • in people between 55 and 87 years of age are between 0.5 and 8.9 mlU per liter.

The TSH high

If the values ​​exceed the established, we will be with TSH High which is often associated with hypothyroidism .This is the reason why the patient may not realize that they have a problem for years. We see them later.

The TSH under

On the other hand if we have a TSH below the levels, it will be a low TSH whose most common causes are:

  • Basedow-Graves disease : (generalized toxic goiter) is an autoimmune disease caused by the presence of antibodies against the TSH receptor. It can cause a hormonal overproduction, therefore, hyperthyroidism with low levels of TSH, thyroxine and high triiodothyronine , and the presence of anti TSH receptor antibodies;
  • Toxic nodular goiter : benign thyroid neoplasm;
  • Thyroiditis : inflammatory process of the thyroid, of an infectious or autoimmune nature ;
  • Too high doses of hormone replacement therapy or other drug treatment;
  • Ovarian Teratoma : a neoplasm composed of tissues embryonic and, therefore, also potentially of thyroid-like tissue, with ovarian location;
  • Non-autoimmune familial hyperthyroidism : this disorder is related to the mutation of a gene that encodes the TSH receptor and it is transmitted in a hereditary way;
  • Pregnancy : in the first three months of pregnancy there is an increase moderate T3 and T4 and a slight decrease in TSH;
  • Hyperemesis of pregnancy : is a disorder that manifests during pregnancy, characterized by repeated episodes of vomiting , which leads to serious imbalances, often linked to unfavorable psychological conditions. biohumoral analyzes will have low TSH and high fT3 and fT4;
  • Choriocarcinoma : is a tumor of the trophoblast, which originates in the villi of the placenta. We will have an increase in T3 and T4 and low levels of TSH;
  • Subclinical hyperthyroidism
  • Dysfunction of the pituitary gland li>
  • Hypothalamus dysfunction

The symptoms of low TSH if accompanied by high values ​​of FT3 and fT4 are typical of hyperthyroidism and, therefore, both:

  • nervousness
  • Easy irritability
  • State of anxiety
  • Presence of palpitations (presence of extrasystoles or ectopic beats, to true arrhythmias)
  • tachycardia
  • Tremor of the extremities
  • alopecia
  • Alterations of the menstrual cycle
  • diarrhea
  • Exophthalmos (eye protruding)
  • Possible presence of eyelid swelling
  • Hyperhidrosis (heavy sweating)
  • Weight loss and weight loss
  • itching
  • Hot flushes

TSH symptoms (in h3)

When I speak We do TSH symptoms to refer to when a high level or high TSH occurs. These would be:

Feeling tired

One of the most common symptoms of hypothyroidism is feeling drained . Thyroid hormone controls the energy balance and can influence whether you feel ready to go or are ready to nap.

As an extreme example, animals that hibernate experience low levels of thyroid leading to their prolonged sleep.

Thyroid hormone receives signals from the brain and coordinates the cells to change their functions, depending on what else is happening in their body.

Those with high levels of thyroid hormone They feel nervous.For example, consider how hot it puts you when you exercise. This is because you are burning calories.

Even when you are sitting, you are burning a small amount of calories. However, in cases of hypothyroidism, your basal metabolic rate decreases , reducing the amount of heat you generate.

In addition, thyroid hormone converts the thermostat into brown fat, which is A specialized type of fat that generates heat. Brown fat is important to maintain body heat in cold climates, but hypothyroidism prevents you from doing your job.

Increase in weight

Unexpected weight gain is another common symptom of hypothyroidism. People with low thyroid not only move less, but also point their livers, muscles and adipose tissue to maintain calories.

When thyroid levels are low, the metabolism changes so Instead of burning calories for growth and activity, the amount of energy you use at rest or your basal metabolic rate decreases. As a result, your body tends to store more calories from the diet in the form of fat.

Because of this, low levels of thyroid hormone can cause weight gain, even if the number of calories consumed remains constant .

Fatigue and depression

Hypothyroidism is related to depression. The reasons for this are not clear, but it could be a mental symptom of a general decrease in energy and health.

Memory problems

Many patients with hypothyroidism complain of "mental confusion " and difficulty concentrating. The way in which this mental nebula is presented varies by person.

Muscle pain, cramps and weakness

Active low thyroid hormone the metabolic shift towards catabolism , which is when the body breaks down body tissues like muscles for energy.

During catabolism, muscle strength decreases, which can lead to feelings of weakness . The process of breaking down muscle tissue can also cause pain.

Everyone feels weak from time to time. However, people with hypothyroidism are twice as likely to feel weaker than usual, compared to healthy people.

Fragile hair and nails

Like most cells, hair follicles are regulated by thyroid hormone.

Because hair follicles have stem cells that have a short lifespan and fast turnover, They are more sensitive to low thyroid levels than other tissues.

Dry and scaly skin

Like hair follicles, Skin cells are characterized by rapid turnover . Therefore, they are also sensitive to losing signs of thyroid hormone growth.

When the normal skin renewal cycle is broken, the skin may take longer to regrow.

This means that the outer layer of the skin has been longer, accumulating damage.Levothyroxine replaces the hormone thyroxine that is not produced sufficiently by the thyroid.

At first, the patient will undergo regular blood tests until the correct dose of levothyroxine is reached.

Hypothyroidism is a lifelong disease, so the patient is likely have to take levothyroxine for the rest of your life.

On the other hand, to treat TSH low, it is best to first look for the cause that causes the problem. Then, in the second place, the treatment can use three different methods:

  • Drugs that inhibit the secretion of thyroid hormones;
  • Therapy with radioactive iodine treatment;
  • Total or partial removal of the gland (replacement therapy)

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