Thyroid hormones are endocrine hormones secreted by the thyroid gland, the body’s endocrine organ. Thyroid hormones mainly include tetraiodothyronine, which is generally referred to as T4, and triiodothyronine, which is generally referred to as T3. The thyroid gland secretes mainly T4 and a small amount of T3, but T4 can be converted to T3 in peripheral tissues. Normal levels of thyroid hormones are important for maintaining normal Normal levels of thyroid hormones play a very important role in maintaining normal physiological functions of the body. For example, thyroid hormones are indispensable for the growth and development of the body and its metabolism, as well as for the normal functioning of the digestive and circulatory systems. Therefore, too much or too little thyroid hormone secretion can lead to diseases and many discomforts. The disease caused by insufficient secretion of thyroid hormones is called hypothyroidism, or hypothyroidism for short. In addition, hypothyroidism can also be caused by a normal production of thyroid hormones, but with insufficient physiological effects. For example, in children, hypothyroidism not only causes short stature, but also low IQ, which is called cretinism. In adults, hypothyroidism can lead to coldness, fatigue, hair loss, anemia, depression, and in some cases, depression. Obesity is a very common disease in modern society. In addition to the above-mentioned symptoms, hypothyroidism can also manifest as obesity, mainly due to mucin deposition in the skin and tissues caused by mucin edema. Due to the combination of hypercarotenemia, the skin of the hands and feet of hypothyroidism patients is ginger yellow, which is why Chinese medicine calls the obesity caused by hypothyroidism yellow fat. If you and your family members experience weight gain, along with symptoms of hypothyroidism such as poor appetite, chilliness, inactivity, and sleepiness, you must go to the hospital for thyroid hormone measurement to see if hypothyroidism is causing obesity. The diagnosis of hypothyroidism is relatively simple and can be made clearly through the measurement of T3, T4 and thyroid stimulating hormone (TSH). To determine the cause of hypothyroidism, further tests for thyroid autoantibodies such as thyroglobulin antibodies (TGAb), thyroid peroxidase antibodies (TPOAb) and thyroid ultrasound are sometimes required. For rare causes of hypothyroidism such as pituitary lesions, a CT or MRI of the pituitary gland is sometimes required to clarify the diagnosis. After the diagnosis of hypothyroidism is clear, the treatment is relatively simple and mainly involves replenishing the lack of thyroid hormones in the body. There are two types of medications for thyroid hormone supplementation, one is thyroid tablets and the other is levothyroxine tablets. The former is made from animal thyroid tissue and contains more T3, but is not stable in potency. The latter is a synthetic thyroid hormone with a constant potency and is more often used temporarily. Although thyroid hormone replacement therapy is simple, it must be used rationally according to each patient’s individual situation. For example, elderly people and patients with heart disease must increase the dose of thyroid hormone supplementation slowly to avoid increasing the burden on the heart and triggering an acute heart attack. On the other hand, for pediatric and pregnant patients with hypothyroidism, it is important to restore normal thyroid hormone levels in the patient’s body as soon as possible. Various symptoms caused by hypothyroidism, including obesity, will slowly disappear under reasonable thyroid hormone replacement therapy, and the patient’s own condition will gradually return to normal. It should be reminded that after the thyroid hormone level in the body is normalized, many patients feel that their symptoms have improved, so they often reduce the dosage of medication on their own, and some even stop the medication, the consequence of this is that the thyroid hormone level in the body will gradually decline again, and the symptoms of hypothyroidism will appear again, so remember that hypothyroidism medication is generally lifelong, do not stop the medication on your own.