Iodine
Iodine is commonly known to have a major effect on thyroid function, being a
main component of the thyroid hormone thyroxine. However, Iodine has many other
effects; from controlling the effects of oestrogen on breast tissue to
protecting against the effects of radioactivity.
Iodine has been a favourite with those who want to lose weight for many years.
As stated above, iodine is the main component of thyroxine, the thyroid
component which controls metabolism. As metabolic rate controls the amount of
"fuel" burned by the body for energy, iodine deficiency can result in a
decreased metabolic rate, hence the supplementation by weight-watchers.
One of the other key functions of iodine is in the formation of the foetal
nervous system. If the mother is iodine-deficient during pregnancy, there is
a significant chance of the baby being born with cretinism (short stature and
extremely low intellectual capacity). Iodine is also an important component
of healthy connective tissues.
Symptoms of Iodine deficiency: Goitre (swelling of the thyroid gland), chronic
fatigue, reduced immune system function, dry skin, excessive oestrogen production,
hypothyroidism. (source)