In recent years, the incidence of thyroid cancer has soared just like the recent stock market, and the number of people suffering from the disease has exceeded the predictions of many doctors and health experts. In the recently released 2014 cancer incidence rate for men in Hangzhou, thyroid cancer has gone from obscurity to the fourth place, while the female incidence rate has directly surpassed breast cancer, lung cancer and other major cancers, ranking first in cancer incidence.
I don’t know if it’s my professional habit or if it is indeed the case, but recently you can often hear people talking about thyroid health in various public places, making this tiny organ a social topic, and along with it, iodized salt and seafood have become a hot dietary concern. Of course, most of the information about the relationship between thyroid disorders and diet is based on falsehoods and has no scientific basis.
Today we will talk about what the thyroid gland is and why there are so many people suffering from thyroid disease. There may be some content that you can’t find the answer to even if you think about it for a long time!
What is the thyroid gland?
The thyroid gland is the largest endocrine gland in the body (endocrine gland means that the gland secretes hormones directly into the bloodstream to regulate the functions of various organs in the body) and is located in the middle of the front of the neck. It is named “thyroid” because of its shape, which resembles two “gauntlets” that protect the body’s trachea, a vital part of the body. The thyroid gland also resembles a butterfly, with two lobes, the left and right, connected by an isthmus. The name of a group of thyroid patients is “The Beautiful Butterfly Flew Away”, which is a great image.
The normal thyroid gland is soft, like a soft rubber, surrounded by two layers of envelope and fixed on the trachea and cricoid cartilage, and feels flexible to the touch. If the thyroid gland is diseased, the texture will change, and it will generally become hard and lose its elasticity. When a normal person swallows, the thyroid gland moves up and down with him or her. If the thyroid gland is diseased, it may become less mobile. Especially in the case of cancer, it is hard to move.
The thyroid gland is a blood-rich organ
The blood flow through the thyroid gland is very rich in blood vessels and nerves, and the blood flow in the entire gland is extremely high, with 5 to 7 milliliters of blood flowing through each gram of thyroid tissue per minute in a normal person. One can imagine how much stress such blood flow can put on the thyroid cells if the body is under such a constant state of stress. In addition, if the heart is not pulsating enough blood, or if the neck access is poor, this can likewise affect the level of blood supply to the thyroid, which is why many patients with thyroid nodules have weak hearts.
The main sources of blood supply to the thyroid gland are the superior thyroid artery and the inferior thyroid artery, most of which originate from the external carotid artery, but also from the bifurcation of the common carotid artery. The inferior thyroid artery arises from the thyrocervical trunk of the subclavian artery. The superior and middle thyroid veins run laterally up the thyroid artery and merge into the internal jugular vein, while the inferior thyroid vein generally injects into the unnamed vein. Its arteries and veins also anastomose with the vessels of the larynx, trachea and esophagus. It is the close relationship of the thyroid blood supply and venous return to the major blood vessels of the neck that makes other diseases of the neck (pharyngitis, cervical spondylosis, carotid stenosis) a frequent cause of thyroid disease.
The lymphatic vessels surrounding the thyroid gland are also extremely rich, and lymphatic fluid drains to the trachea, mediastinum, and anterior cervical lymph nodes of the larynx via the lymphatic plexus surrounding the follicles. Because of the intricate lymphatic channels in the neck, lymph node metastases are often found at the same time as thyroid cancer is detected clinically.
What does the thyroid gland do?
The thyroid gland’s main function is to synthesize thyroid hormones and regulate the body’s metabolism. After entering the cells, iodide, through the action of oxidase, produces active iodine which rapidly combines with the tyrosine group on the thyroglobulin molecule in the glial cavity to form monoiodotyrosine (MIT) and diiodotyrosine (DIT). Iodinated tyrosine, through the action of oxidase, causes MIT and DIT to couple and combine to form thyroxine (T4), and MID and DIT to couple and combine to form triiodothyronine ( The synthesized thyroxine (T4) and triiodothyronine (T3) are secreted into the circulation and bound mainly to plasma thyroxine-binding globulin (TBG) for transport and regulation of thyroxine concentrations in the blood. Thyroxine (T4) is deiodinated in peripheral tissues to form the biologically active T3 and the biologically inactive rT3, respectively, and the shed iodine can be reused.
In hyperthyroidism, blood T4, T3 and rT3 are increased, while in hypothyroidism, all three are below normal values. The amount of thyroxine secretion is regulated by TSH, which is secreted by pituitary cells. In turn, TSH is controlled by TRH secreted by the hypothalamus, thus forming the hypothalamic-pituitary-thyroid axis, which regulates thyroid function. When too much thyroid hormone is secreted, thyroid hormone will in turn stimulate the hypothalamus and pituitary gland to suppress TRH secreted by the hypothalamus and TSH secreted by the pituitary gland, thus achieving the effect of reducing thyroid hormone secretion, which is also called feedback regulation.
From the above description, we can see that if there is a problem with the thyroid gland, the cause may be the thyroid gland itself, or it may be the pituitary gland or hypothalamus, which is the commander-in-chief of the whole body’s endocrine system, and the healthy operation of both is closely related to circadian rhythm and mood. If you often sleep late and stay up late, or if you are in a negative balance, it will easily lead to dysfunction of the pituitary hypothalamus system, which in the long run will not only damage the thyroid axis, but also involve the gonadal axis (estrogen/progesterone levels, gynecological diseases, breast diseases) and the adrenal axis (patients with thyroid disease often have typical adrenal fatigue, manifesting as long-term weakness and drowsiness or even adrenal tumors), and eventually the pituitary gland will swell due to The pituitary gland eventually swells due to overload and produces pituitary tumors, etc.
What are the effects of thyroid hormones?
The basic functions of thyroid hormone are two: First, to promote growth and development. Thyroid hormone can promote fetal development and newborn growth and bone maturation. Thyroid hormones also have an important effect on the intelligence of children and the memory, thinking ability and reactions of adults. Many thyroidectomized patients who are not supplemented with adequate amounts of thyroid hormone experience slower reactions and memory loss, some patients even experience deterioration in language and comprehension, and some older adults may even develop dementia.
The second basic function of thyroid hormone is to promote substance metabolism, which is important for maintaining normal substance and energy metabolism in the body, including the breakdown and utilization of sugar, protein, fat, water salts and vitamins. Thyroid hormones promote thermogenesis, facilitate oxygen consumption and increase the basal metabolic rate. Therefore, patients with hyperthyroidism tend to be thin, and also have manifestations such as fear of heat, excessive sweating and hyperappetite. Hypothyroid patients, on the other hand, show signs of chilliness, less sweating, and weight gain.
Because thyroid hormones are closely related to our metabolism and the metabolism of nutrients, diet is another major reason for the high incidence of thyroid disorders. Improper diet structure, inappropriate meal ratios, poor dieting methods, skewed nutritional intake, chronic food allergies can all affect the healthy functioning of the thyroid gland in some cases (and it is by no means only related to the amount of iodine consumed), and the severely reduced detoxification and antioxidant capacity of the modern human body allows many external stimuli to damage our body’s The “golden nail”, especially the various types of thyroid inflammation, is closely related to this.
Conclusion
Although the thyroid gland is shaped like a shield that protects us from harm, it is actually very susceptible to injury itself. Our golden nail is so vulnerable to stress, poor diet, diurnal disruption, nutritional bias, environmental toxins, hormonal imbalance and many other factors. Hyperfunction, inflammation, nodules, cancer. If we don’t treat this “beautiful butterfly” well, it can easily disappear!