Common causes of hypothyroidism include: 1. Emotional stimulation: due to mental stimulation, resulting in liver qi stagnation, liver depression leads to spleen deficiency, then abnormal transportation and transformation, and internal production of damp phlegm. 2, improper diet: due to improper diet, damage to the spleen and stomach, deficiency of middle qi, abnormal transportation and transformation, diet water and grain can not be transported and transformed, phlegm and drinks are generated internally; phlegm and dampness are congested, obstructing qi and damaging spleen yang. The spleen is the foundation of the posterior. If the spleen yang is weak, the kidney fire will nourish it over time, resulting in a deficiency of both the spleen and the kidney, which leads to loss of appetite, coldness, drowsiness and laziness, and general swelling. 3, the external evil invasion: most see wind-heat poisonous evil, from the mouth and nose invasion, poisonous evil gathered in the front of the neck, then see the pharynx and the front of the neck swelling, pain; if over use of cold things, internal injury to Yang, although the neck heat and toxicity removed, pain disappeared, but can be seen pronunciation low, fear of cold, and even swelling and other symptoms. 4, surgical creation or drug poisoning: due to the thyroidectomy or taking some toxic drugs (such as the treatment of hyperthyroidism of Western medicine), the body’s vital energy is damaged, resulting in the loss of nourishment of the internal organs, functional decline, can show a series of signs of deficiency.