Factfinder
A-Z of vitamins and minerals
Iodine
RDA up to 150micrograms for adults.
It is not stored in the body and we therefore need a regular intake.
Where do you get it?
Iodine is in seafood, kelp and sea salt; it's also found in milk, eggs and meat, depending on the soil conditions and diet of the animals.
We usually get enough iodine from food and, if necessary, using sea salt in place of refined salt. Artificially iodised salt is not as good as it also contains aluminium and other chemicals.
Seaweed has plentiful amounts of iodine, and has been eaten for thousands of years.
Actions:
Iodine is needed by the thyroid gland to produce the hormones used all over the body. These hormones help produce energy from fat, control cholesterol levels and keep weight stable. They also are involved in reproduction, nerves and bone, and keep skin, hair, nails and teeth in good condition.
Too much:
Too much iodine can cause goitre and skin rashes. Normal dietary intake is unlikely to have any toxic effects.
Too little:
Lack of iodine causes the thyroid gland to swell in an attempt to extract iodine from the blood. (This is goitre.) Long term, this can cause symptoms of obesity, constipation, weakness and mental slowness, leading to insanity.
Supplement:
Kelp tablets are a good source of iodine if a supplement is needed. Multi-minerals usually contain some iodine.