Hypothyroidism, also known as underactive thyroid or low thyroid, is a disorder of the endocrine system where the thyroid gland fails to produce enough thyroid hormone. This condition can lead to various symptoms, including intolerance to cold, fatigue, constipation, depression, and weight gain. In some cases, there may be swelling of the front part of the neck due to goiter. Untreated hypothyroidism during pregnancy can result in growth and intellectual development delays in the baby or cretinism.
The most common cause of hypothyroidism worldwide is inadequate dietary iodine. In regions with sufficient iodine intake, the primary cause is Hashimoto’s thyroiditis, an autoimmune condition. Other less common causes include previous treatment with radioactive iodine, injuries to the hypothalamus or anterior pituitary gland, certain medications, congenital absence of a functional thyroid, or prior thyroid surgery. Diagnosis of hypothyroidism typically involves blood tests to measure thyroid-stimulating hormone (TSH) and thyroxine levels.
Salt iodization has been successful in preventing hypothyroidism in many populations. The condition can be effectively treated with levothyroxine, a synthetic thyroid hormone. The dosage is adjusted based on symptoms and the normalization of thyroxine and TSH levels. Thyroid medication is generally considered safe during pregnancy. While adequate dietary iodine is essential, excessive amounts can worsen certain types of hypothyroidism.
Globally, it is estimated that around one billion people suffer from iodine deficiency, but it is unclear how often this results in hypothyroidism. In the United States, hypothyroidism affects approximately 0.3-0.4% of the population. Subclinical hypothyroidism, a milder form characterized by normal thyroxine levels and elevated TSH levels, is believed to occur in 4.3-8.5% of people in the United States. Hypothyroidism is more prevalent in women than men, and it becomes more common with age. Dogs are also known to develop hypothyroidism, and in rare cases, cats and horses can be affected.
It is important to note that the information provided is based on Wikipedia as a source. Hypothyroidism can manifest with various symptoms and signs, which may be related to the underlying cause or the direct effect of inadequate thyroid hormone levels. Myxedema coma is a rare but life-threatening condition associated with extreme hypothyroidism. Hypothyroidism can also have implications during pregnancy, potentially leading to infertility, increased risk of miscarriage, pre-eclampsia, lower offspring intelligence, and infant death around the time of birth.
In children, hypothyroidism may present with symptoms such as drowsiness, feeding difficulties, constipation, enlarged tongue, umbilical hernia, dry skin, decreased body temperature, and jaundice. Delayed growth and development can occur, potentially resulting in intellectual impairment. Older children and adolescents may experience fatigue, cold intolerance, sleepiness, muscle weakness, delayed growth, weight gain, and irregular menstrual cycles in girls.
Hypothyroidism can be caused by inadequate thyroid gland function (primary hypothyroidism), insufficient stimulation by thyroid-stimulating hormone (secondary hypothyroidism), or insufficient release of thyrotropin-releasing hormone (tertiary hypothyroidism). Iodine deficiency is the leading cause of primary hypothyroidism and endemic goiter worldwide. Hashimoto’s thyroiditis, an autoimmune disease, is the most common cause in regions with adequate iodine intake.
It is crucial to consult with a healthcare professional for accurate diagnosis, personalized treatment, and management of hypothyroidism. This article is not intended as medical advice, and readers should rely on the expertise of their healthcare provider for their specific circumstances. The information provided is based on Wikipedia as a resource and should be used as a starting point for further research. The content of this article has not been evaluated by the FDA, and readers are advised to seek professional medical advice before making any dietary changes, diagnoses, or treatment decisions.