The thyroid is a butterfly-shaped gland in the front of the neck. Its primary function is to produce the hormones triiodothyronine (T3) and thyroxine (T4), which help regulate metabolism and aid in brain development, digestive function, muscle control, and mood regulation.

When the thyroid produces either too much or too little of these hormones, it causes the gland to work inefficiently, leading to disorders such as hyperthyroidism and hypothyroidism, the two most common types of thyroid disease. Other thyroid-related conditions include thyroiditis, thyroid nodules, goiter, and thyroid cancer.

Frequently Asked Questions

  • Is thyroid disease hereditary?

    Certain autoimmune thyroid diseases, such as Hashimoto’s disease and Graves' disease, can be hereditary. Other risk factors for thyroid diseases include being female, having another autoimmune disease, pregnancy, and more.

  • What are the symptoms of thyroid disease?

    Symptoms of thyroid disease depend on whether too much or too little thyroid hormone is being produced. Symptoms of hypothyroidism (low hormone levels) include fatigue, weight gain, hair loss, and feeling cold. Symptoms of hyperthyroidism (high hormone levels) include weight loss, rapid heart beat, and insomnia. Symptoms of other forms of thyroid disease can include a swollen neck, among others.

  • What causes thyroid disease?

    The causes are varied. Autoimmune diseases such as Grave’s disease and Hashimoto’s disease cause the thyroid to produce too much or too little thyroid hormone. Pregnancy can also result in an under- or overactive thyroid. Other causes of thyroid disease include thyroiditis, radioactive iodine treatment, and possibly radiation for head and neck cancers.

  • Can you lose weight with thyroid disease?

    People with hyperthyroidism often experience weight loss. The more severe the hyperthyroidism, the greater the weight loss. Weight loss can also occur with other conditions that involve an excess of thyroid hormone, such as thyroiditis.

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