Iodine
Minerals & trace elements
Essential to the thyroid, and almost absent from land plants.
Seaweeds are the only serious plant sources, and kombu contains so much that daily use would be excessive. Iodized salt does the rest.
Effects and benefits
The raw material of thyroid hormones, which set the energy of the whole body and the development of the brain. It contributes to the thyroid, energy and cognitive function. And during pregnancy, needs rise by a third.
Without iodine, the thyroid swells to try to capture more: that is goiter, once so common in the Alps that it was part of the landscape. Switzerland iodized its salt in 1922, France in 1952, and endemic goiter disappeared.
It contributes to the normal production of thyroid hormones and normal thyroid function, to normal cognitive function, to normal energy-yielding metabolism, to the normal functioning of the nervous system and to the maintenance of normal skin (Regulation 432/2012).
By sex and age: EFSA sets the adequate intake at 150 µg a day for an adult, 200 during pregnancy and breastfeeding (EFSA, 2014). The fetal brain depends on the mother's thyroid hormones during the first months: iodine deficiency during pregnancy is the leading preventable cause of intellectual disability in the world (WHO).
Sources: EU Regulation 432/2012 · EFSA, 2014 · WHO
Where to find it (44)
- Arame
- Atlantic wakame
- Baris-baris
- Brachytrichia
- Bull kelp (nereocystis)
- Catenella
- Ceratodictyon
- Cochayuyo (bull kelp)
- Culot seaweeds
- Cuvie
- Dictyopteris
- Dictyota
- Dulse
- Fucus
- Garganatis
- Gayong-gayong
- Giant kelp
- Gracilaria seaweeds
- Grateloupia
- Green bubble weed
- Hypnea
- Knotted wrack
- Kombu
- Luche (Chilean nori)
- Lukot-lukot
- Lumot (green seaweed)
- Mozuku
- Nori
- Oarweed (kelp)
- Ogonori
- Padina
- Pepper dulse
- Portieria
- Sea grapes / umibudo
- Sea lace
- Sea lettuce
- Sea spaghetti
- Shihuacai seaweed
- Sugar kelp (royal kombu)
- Tabtaba (oyster thief seaweed)
- Tsunomata
- Turbinaria
- Valonia
- Wakame