Cigarettes and thyroidSmoking is one of the culprits of lung cancer, which is known as. But beyond that, smoking can also have an impact on
Cigarettes and thyroid
Smoking is one of the culprits of lung cancer, which is known as. But beyond that, smoking can also have an impact on the thyroid gland. The products of tobacco combustion, such as nicotine and thiocyanate, can interfere with the development of the nervous system and endocrine system.
1 the effect of smoking on thyroid function
The effect of smoking on thyroid function is the long-term effect of comprehensive result of multiple factors, age, smoking history, smoking and smoking and smoking, as well as the basis of thyroid function, body quality, area (or rich iodine in iodine deficiency area) related factors.
The specific mechanism by which smoking affects thyroid function is unknown, and is related to the product of tobacco combustion and its metabolites in human body. The nicotine, thiocyanate and benzopyrene more clearly. Nicotine itself does not affect the secretion and role of thyroid hormones, but can stimulate the sympathetic nervous system. Animal experiments have shown that thiocyanate has anti thyroid function. And benzopyrene and other tobacco components increased liver microsomal enzyme activity, accelerated the degradation of thyroid hormone.
2 smoking and goiter
A large number of epidemiological data show that smoking can promote the occurrence of thyroid enlargement, and long-term smoking, "old smokers", especially iodine deficiency areas, which are more prone to nodular goiter.
The mechanism of smoking induced goiter has not been elucidated, but the role of thiocyanate should not be ignored. Thiocyanate is the product of the detoxification of cyanide, the content of thiocyanate in smokers is proportional to the degree of smoking, and in vitro experiments have confirmed that it has the role of inhibition of thyroid function and thyroid goiter. The phenomenon of smoking induced goiter occurred in patients with a family history of goiter, indicating that genetic factors also play a role.
3 smoking and autoimmune thyroid disease
The effect of smoking on the human immune system involved in cellular immunity and humoral immunity, can inhibit the activity of natural killer cells, increasing the total number of T cells decreased, CD4+ cells, CD8+ cells increased, serum IgG, IgM and IgA levels also decreased by 10%-20%. It has been proved that the relationship between cigarette smoking and autoimmune thyroid disease has been paid more and more attention.
Smoking can increase the occurrence of hypothyroidism, and may be related to thiocyanate. In patients with postpartum thyroiditis, reported smoking more than 20 cigarettes per day and thyroid dysfunction have significant correlation, especially related to postpartum long-term hypothyroidism.
The smoke of anthracene role can not be ignored, some scholars use 3- methylcholanthrene in susceptible rats induced autoimmune thyroiditis model.
4 smoking and hyperthyroidism (hyperthyroidism)
It is well known that hyperthyroidism (Graves disease) is a common autoimmune thyroid disease, and its pathogenesis is related to genetic, infectious and environmental factors. Smoking may be one of the environmental stimuli, which can induce the genetic susceptibility of individuals. In vivo, the inhibitory activity of T lymphocytes was decreased, and the immune surveillance function was impaired, which led to the clonal proliferation of T helper lymphocytes in the thyroid gland, which induced Graves hyperthyroidism.
In addition, there are also reports of smoking in patients with hyperthyroidism, antithyroid drug treatment after discontinuation of the relapse rate is higher than non-smokers.
5 smoking and Graves ophthalmopathy
The relationship between smoking and Graves ophthalmopathy (Graves eye disease) is recognized, the incidence and severity of eye disease, incidence and severity of eye disease is significantly higher than that of non-smokers. Not only that, smoking also affects the treatment of Graves ophthalmopathy. It is reported that the incidence of Graves eye disease in 60% of the patients with hyperthyroidism, but the incidence of Graves eye disease is lower than that of the current smokers. In addition, smoking can also reduce the effect of antithyroid drugs, retrobulbar radiotherapy, etc..
It is not clear how smoking triggers or aggravates Graves ophthalmopathy. At present, including its possible mechanism: 1) smoking has direct irritation, inflammation caused by soft tissue such as eye tears, burning sensation, conjunctival edema; 2) smoking induced immune function disorder, is involved in the pathogenesis of Graves ophthalmopathy. Smoking may also affect the structure of the TSH receptor, increase its immunogenicity, so that thyroid stimulating antibody (TSAb) production increased, and the orbital tissue of the TSH receptor reaction enhanced, resulting in the occurrence of thyroid associated ophthalmopathy. 3) cigarette smoking can lead to hypoxia, induce the expression and activity of cytokines, growth factors, adhesion molecules and so on, cause the disorder of local microenvironment, and influence the development and progression of Graves ophthalmopathy.
6 smoking and thyroid disease in infants and young children
The extent of thyroid enlargement in pregnant smokers was parallel to that of pregnant women. Smoking during pregnancy (including passive smoking) infants growth retardation, lighter weight, thyroid volume increased, umbilical cord blood TSH normal or decreased, T4, FT4I normal or increased, thiocyanate and Tg content were increased, and the umbilical cord blood thiocyanate content and maternal blood concentration is related. Smoking was positively associated with.
In conclusion, smoking may be an important environmental factor affecting thyroid function and thyroid disease. For your own and others' health, it is best to quit smoking and avoid passive smoking.