One of the most important thyroid hormones is thyroxine (T4). Its amount is 90% of all hormones produced. The function of the substance is to regulate energy and plastic metabolism in the body. Normally, free T4 in women is approximately 0.02–0.04% of the total thyroxine content in the body.
What is the significance of the hormone
Thyroxine is produced by the follicular cells of the thyroid gland. Maintaining a constant level of this hormone is of particular importance due to its long-term effects on the body and its ability to accumulate in tissues.
Normal development of cells is impossible without thyroxine, therefore, its excess or deficiency affects the state of health. Due to the sufficient production of hormones, a person’s physical activity, the speed of thought processes increases, and the period of wakefulness increases.
Functions of thyroxine:
- activates and regulates metabolic processes in the body;
- stimulates the metabolism of vitamins;
- participates in the control over the growth and development of the body;
- enhances protein synthesis;
- normalizes heart function;
- thickens the inner lining of the uterus in women;
- increases body temperature;
- participates in oxidative processes in the cells of the whole organism, in particular, the brain;
- stimulates the formation of vitamin A in the liver.
The role of thyroxine for a woman and her health
Thyroxine is especially important for women, because how the reproductive system will work depends on it. The process of egg maturation and ovulation takes place under the direct control of this hormone.
A low level indicates hypothyroidism, the presence of which can cause problems with ovulation and lead to infertility. With this disease, women experience heavy bleeding and a long menstrual cycle.
High levels of the hormone indicate hyperthyroidism, which can lead to frequent miscarriages or negatively affect the ability to conceive. T4 sv regulates metabolism, which leads to the normalization of body weight. Thanks to the hormone, the vessels are freed from cholesterol plaques, and the risk of blood clots is reduced. In addition, T4 helps the body absorb calcium.
It should be noted that in some cases with subclinical hyper- or hypothyroidism, the total T4 may not go beyond the permissible values, while the free hormone exceeds the maximum limit several times. It is for this reason that it is important to pass the test for free T4 – the results will be more reliable.
The hormone rate in a woman does not change throughout her life, slightly decreasing during menopause. In the summer, the concentration becomes lower, the maximum concentration is reached in the autumn-winter period. An increase in T4 levels is preceded by obesity, a high serum bilirubin content, an overdose of hormonal drugs.
During pregnancy, the level of the hormone rises. High rates in pregnant women usually do not require treatment. However, if the level is low, the hormone content should be adjusted to ensure the normal development of the child.
Increased and decreased hormone levels. Symptoms and Diseases
An increased content of free thyroxine is usually accompanied by the following symptoms:
- excessive sweating;
- irritability;
- increased fatigue;
- increased heart rate;
- interruptions in the work of the heart;
- tremor;
- weight loss;
- with prolonged elevated levels of the hormone in the blood, patients experience osteoporosis and the risk of injury increases.
Ft4 in increased concentration releases excess energy, accelerating the process of decay of energetic substances. As a result, a person’s body weight decreases, and the released energy is sent to other parts of the body, increasing physiological reactions to a high level.
The analysis results suggest the presence of toxic goiter, thyroiditis, choriocarcinoma, chronic liver diseases, obesity, hyperthyroidism, nephrotic syndrome, myeloma.
The reduced content of the hormone is accompanied by the following symptoms:
- decrease in body temperature, feeling of coldness, chilliness;
- constant weakness and feeling of tiredness;
- numbness of the limbs;
- mood swings;
- headache;
- tenderness in the area of muscles and joints;
- brittle hair and nails;
- increased dryness of the skin;
- memory, thinking and attention are significantly reduced;
- slowing down the heart rate;
- impaired vision and hearing;
- slowing down the digestion processes;
- violation of the menstrual cycle;
- increase in body weight.
Low st4 can be caused by diseases such as hypothyroidism, inflammation of the thyroid gland. Also, an overdose of drugs during the treatment of increased thyroid function, treatment with radioactive iodine, and surgical interventions on this organ may affect the decrease in indicators .