Minerals
Iodine (Potassium Iodide)
Also known as: Potassium iodide · Lugol's iodine · Nascent iodine
Essential for thyroid hormone production. Deficiency causes goitre, hypothyroidism, and cretinism. Iodised salt has eliminated deficiency in most developed nations — supplementation needed mainly for vegans and those avoiding salt.
Effective Dose
150–220mcg / day
per clinical evidence
Evidence Level
Strong
Minerals
Mechanism
Thyroid hormone (T3/T4) synthesis substrate
primary action
Best For
Thyroid health
Metabolism, Cognitive development, Pregnancy
This profile is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications.
What Is Iodine (Potassium Iodide)?
Iodine is incorporated into thyroid hormones thyroxine (T4) and triiodothyronine (T3) — the body's primary metabolic regulators. A single T4 molecule contains 4 iodine atoms; T3 contains 3. Iodine deficiency is the leading preventable cause of brain damage and intellectual disability worldwide.
How It Works: The Science
Iodide is actively concentrated in thyroid follicular cells via the sodium-iodide symporter (NIS), oxidised by thyroid peroxidase (TPO), and incorporated into thyroglobulin to form MIT and DIT, which couple to form T3 and T4. Thyroid hormones regulate basal metabolic rate, thermogenesis, heart rate, protein synthesis, and virtually every organ system.
Primary Mechanism
Thyroid hormone (T3/T4) synthesis substrate
Evidence-Based Benefits
Dosage Guide
Effective Dose
150–220mcg / day
RDA: 150mcg/day adults; 220mcg pregnancy; 290mcg lactation. Most iodised salt provides adequate intake. Supplementation required for: strict vegans, those avoiding iodised salt, sea vegetables, and dairy.
Safety Profile & Side Effects
Excess iodine causes thyroid dysfunction — both hypo- and hyperthyroidism. Tolerable UL: 1100mcg/day. Avoid high-dose iodine supplementation (Lugol's, high-dose kelp) without thyroid monitoring. Kelp is an unreliable source due to highly variable iodine content.
Who Should (and Shouldn't) Take It
Vegans (low dietary iodine without dairy or iodised salt), pregnant and breastfeeding women, and those not using iodised salt. Most people in developed countries meet needs via iodised salt and dairy.
Frequently Asked Questions
Related Ingredients
Medical Disclaimer
Ingredient profiles are for informational purposes only and do not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications. Full disclaimer →