The thyroid is located in the neck, just below the glottis cartilages, over the initial portion of the trachea.
The two main thyroid hormones are thyroxine and the triiodothyronine, which respectively contain four and three iodine atoms in their molecules. Both are derived from the amino acid tyrosine.
Iodine thyroid hormones control the metabolic activity of virtually every cell in the body.
In the presence of these hormones, cellular respiration of all cells increases, with overall increase in body activity.
Another important thyroid hormone is calcitonin, which works by decreasing the amount of calcium in the blood.
Goiter is an abnormal enlargement of the anterior neck caused by an enlarged thyroid. This problem occurs in at least 5% of the population worldwide. The most common cause is lack of iodine, the chemical that the thyroid uses to make hormones.
Again, in the opinion of experts in the field, approximately one hundred million people do not have enough iodine in their diet. They point out, however, that this problem has been solved by adding iodine to table salt. However, even with the proper amount of iodine, the thyroid gland can increase in size, creating a goiter. This can occur in various thyroid diseases, such as hyperthyroidism, hypothyroidism, thyroiditis, and thyroid cancer. Doctors warn that some goiters develop at normal hormone levels and do not require treatment.
The body is "accelerated" due to excess thyroid hormone in the blood. These cases are approximately ten times more frequent in women, affecting around 2% of them worldwide. Graves' disease, a very common manifestation of the disease, is caused by immune system problems, with a higher prevalence in families that have already had cases. In the United States, the disease affects approximately 2.5 million women.
Common symptoms of the disease are: increased heart rate; nervousness; muscle weakness; sweating; weight loss; tremors; skin changes; decreased menstrual flow; goiter; hair loss. It should be noted that symptoms do not occur simultaneously and must be diagnosed by specialists.
Hypothyroidism causes the body to work slowly. This occurs when there is insufficient amount of thyroid hormone in the blood. Statistics show that more than five million Americans have the disease, even though many are unaware of its existence. Experts point out that the prevalence is higher among women.