The thyroid is a small, butterfly-shaped gland located in the front of the neck, responsible for producing hormones that regulate the body's metabolism, energy levels, and overall growth and development. The two main hormones produced by the thyroid are triiodothyronine (T3) and thyroxine (T4), which play a crucial role in controlling how the body uses energy, maintains temperature, and supports the function of vital organs like the heart and brain.

Thyroid disorders are common and can result from either overactivity (hyperthyroidism) or underactivity (hypothyroidism) of the gland. Hyperthyroidism leads to symptoms like rapid weight loss, anxiety, and a fast heart rate, while hypothyroidism can cause fatigue, weight gain, and depression. Conditions like Hashimoto's thyroiditis (an autoimmune cause of hypothyroidism) and Graves' disease (an autoimmune cause of hyperthyroidism) are also linked to thyroid dysfunction.