A goitre is a swelling in the throat that is a tumour of the thyroid gland. It may be a temporary condition that does not require treatment, or it may be a sign of another thyroid problem, which may be serious enough to require surgery. Goitre is caused by a lack of "iodine" or hereditary, can be caused by smoking, or too much stress... The hormones produced by the thyroid gland are necessary for the functioning of the heart, the brain, the muscles, the digestive system... Signs: nervousness, irritability, disturbed sleep, trembling hands, weight loss, heart palpitations, prolonged sweating, breathing problems...