Hypothyroidism

The thyroid is a small, butterfly-shaped gland in your neck that produces hormones called T3 and T4. These hormones help control energy use, metabolism, and many body functions. When the thyroid is underactive, it may not produce enough of these hormones, which can slow down your body's processes.

Hypothyroidism affects nearly 5 out of 100 Americans over age 12, according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). It is more common in women, especially those over age 60. Research suggests it may also impact infants, children, and people during pregnancy.

There are main types, including primary (most common, affecting the thyroid directly), secondary (pituitary gland issue), tertiary (hypothalamus problem), and subclinical (mild with slightly high TSH). In some cases, it starts at birth or develops slowly over years. Many people manage it well with treatment, but talk to your doctor for guidance.

Symptoms might appear gradually, and early stages could go unnoticed. Infants and children may face growth delays if not caught early. With proper care, most lead healthy lives, but consult a healthcare professional if concerned.

The most common cause is Hashimoto's disease, an autoimmune condition where the immune system attacks the thyroid (Mayo Clinic). Other forms of thyroiditis, like postpartum, subacute, or silent thyroiditis, may also lead to low hormone levels after initial inflammation. In rare cases, too little or too much iodine in the diet could play a role, though iodine deficiency is uncommon in the U.S. (NIDDK).

Hypothyroidism might result from thyroid surgery, radiation therapy, or radioactive iodine treatment for other thyroid issues. Certain medicines, such as lithium or amiodarone, could interfere with hormone production. Congenital hypothyroidism occurs when babies are born with an underactive or missing thyroid gland.

Less often, problems with the pituitary gland or hypothalamus may cause secondary or tertiary types. Risk factors include being female, over age 60, family history of thyroid disease, recent pregnancy, or other autoimmune conditions like type 1 diabetes or rheumatoid arthritis (Cleveland Clinic). These factors might increase chances, but not everyone with them develops it.

Doctors often start with a physical exam, checking for thyroid enlargement or swelling, and review your symptoms and medical history. Blood tests are key: high TSH (thyroid-stimulating hormone) with low free T4 levels may indicate hypothyroidism. Antibody tests, like anti-TPO, could confirm autoimmune causes such as Hashimoto's.

In some cases, ultrasound or thyroid scans might check for nodules or inflammation. For infants, newborn screening is routine to catch congenital cases early (NIDDK). Always consult your healthcare provider, as symptoms can overlap with other conditions.

See your doctor if you notice ongoing fatigue, unexplained weight gain, sensitivity to cold, or dry skin that doesn't improve. Children with poor growth, delayed teeth, or mental development issues need prompt checks. Women with heavy or irregular periods or fertility concerns should talk to a healthcare professional soon.

If you're on thyroid medicine and symptoms return, contact your provider for dose adjustments. Research suggests regular follow-ups help manage it well. Go to the ER for severe signs like low body temperature, slow heartbeat, confusion, or breathing trouble, which could signal myxedema coma—a rare, serious complication (Cleveland Clinic).

You may not be able to prevent hypothyroidism, especially autoimmune types like Hashimoto's. However, ensuring enough iodine in your diet through iodized salt or seafood might help in areas with deficiency risks, but avoid excess if you have autoimmune thyroid issues (NIDDK). Talk to your doctor about supplements.

If you have risk factors like family history or recent radiation, regular screening could catch it early. Newborn screening prevents issues in babies. A healthy lifestyle with balanced eating and exercise may support overall thyroid health, but consult a healthcare provider for personalized advice.