hypothyroidism

Hypothyroidism is the body idling too low. With too little thyroid hormone, metabolism slows across the board, so the whole system feels sluggish and cold.

Common symptoms mirror that slowdown: fatigue, weight gain, feeling cold, dry skin, constipation, slowed thinking, low mood, and in women heavier or irregular periods. Worldwide the leading cause where iodine is plentiful is Hashimoto’s thyroiditis, an autoimmune attack on the gland; iodine deficiency is the leading cause globally. Blood tests typically show a high TSH with low thyroid hormone, as the pituitary shouts louder at a gland that cannot keep up.

The standard treatment is a daily tablet of levothyroxine, synthetic T4, with the dose adjusted to bring TSH back into the normal range. Treated well, people usually feel normal. Untreated severe hypothyroidism can rarely progress to myxedema coma, and untreated deficiency in pregnancy or infancy can harm brain development, which is why newborns are routinely screened.