Iodine

About Iodine

Iodine is a trace mineral that is an essential component of the thyroid hormones thyroxine T4 and triiodothyronine T3, which regulate metabolic rate, growth, development and body temperature. Official intake recommendations are higher in pregnancy and lactation, when thyroid hormone production, fetal needs and urinary losses increase. Iodine deficiency is regarded as the leading preventable cause of intellectual disability worldwide. Before iodization programs, endemic goiter and cretinism were common in inland and mountainous regions far from the sea. Cretinism involves severe intellectual disability, deafness, spasticity and stunted growth. Salt iodization, adopted by most countries, has greatly reduced iodine deficiency disorders. Excess iodine can also disturb thyroid function, causing hyperthyroidism, known as the Jod Basedow effect, or hypothyroidism, and an upper intake level has been set. Kelp supplements vary widely in content. Population status is assessed by median urinary iodine concentration, since day to day variation makes individual measurements unreliable.