Iodine
Essential trace mineral with EFSA claims for thyroid function and cognitive function, critical in pregnancy, common gap in non-fortified diets.
Why
Iodine is essential for thyroid hormone synthesis (T3, T4). EFSA has authorised health claims for normal thyroid function, normal cognitive function, normal energy-yielding metabolism, and skin maintenance. Deficiency causes goitre and, in pregnancy, irreversible developmental cognitive impairment (cretinism in severe cases, subclinical cognitive deficit in mild cases). Salt iodisation has reduced deficiency in many countries but is incomplete in much of Europe, and vegan/plant-based diets often need supplementation.
How it works
Incorporated into thyroxine (T4) and triiodothyronine (T3) at the thyroid follicular cell apical membrane (TPO-mediated organification). T3/T4 then regulate basal metabolic rate, neurodevelopment, growth, and many other systems.
Expected onset · Thyroid-function effects over weeks; cognitive-developmental outcomes assessed over years (paediatric context)
How to take
Dosage
RDI: 150 µg/day (adults). Pregnancy: 220–250 µg/day. Breastfeeding: 290 µg/day. Avoid sustained intake above 600 µg/day from supplements.
Timing
With or without food
On the label
'Potassium iodide' (basic salt) or 'kelp' (variable iodine content, less predictable). Stated micrograms per dose.
Ideal for
Pregnant and breastfeeding women (highest priority); women planning conception; vegans without seaweed intake; people not using iodised salt; populations in iodine-deficient regions.
Safety
Evidence
EFSA-authorised claims for four functions including thyroid and cognition. Bath 2013 Lancet UK ALSPAC analysis: even mild gestational iodine deficiency was associated with reduced child verbal IQ at 8 years, anchors the pregnancy supplementation rationale. Zimmermann 2011 Nat Rev Endocrinol systematic review confirms the cognitive-developmental impact of mild-to-moderate iodine deficiency.
- EFSA Reg 432/2012 authorised claims, iodine and thyroid function, cognitive function, energy-yielding metabolism, skin maintenance
- Bath et al., Lancet 2013, effect of inadequate iodine status in UK pregnant women on cognitive outcomes in their children (ALSPAC, n=1,040)
- Zimmermann, Nat Rev Endocrinol 2011, the role of iodine in human growth and development (review)
Where to get it
Shop Iodine on AmazonSponsored · As an Amazon Associate, Healicus earns from qualifying purchases.