Iodine
Also known as: Potassium Iodide, Sodium Iodide
An essential trace mineral for thyroid hormone synthesis and metabolic regulation.
What it is
Iodine is an essential trace mineral required exclusively for the synthesis of thyroid hormones T3 (triiodothyronine) and T4 (thyroxine). It is one of the most widespread micronutrient deficiencies worldwide despite being readily available through iodized salt and seafood. Subclinical deficiency is common, particularly in pregnant women and populations avoiding processed foods.
How it works
The thyroid gland concentrates iodine from the bloodstream and incorporates it into thyroglobulin via thyroid peroxidase enzyme activity. The resulting thyroid hormones regulate basal metabolic rate, thermogenesis, protein synthesis, and neurological development — making iodine indirectly critical to energy, cognition, and weight management.
Clinical dose range
150–300 mcg/day
RDA: 150 mcg/day for adults; 220 mcg for pregnancy; 290 mcg for lactation. Most supplements provide 150–250 mcg. The UL is 1,100 mcg/day. High-dose iodine supplements (mg range) require medical supervision.
Forms comparison
What to look for on the label
- Exact iodine dose stated in mcg (not just 'iodine from kelp')
- Potassium iodide or sodium iodide as the source for consistent dosing
- Third-party tested for actuals (especially important for kelp-based sources)
- Does not approach or exceed the 1,100 mcg UL
Health goals supported
Safety & dosing notes
Excess iodine can paradoxically inhibit thyroid function (Wolff-Chaikoff effect). Individuals with autoimmune thyroid disease (Hashimoto's, Graves') should consult a physician before supplementing. The UL is 1,100 mcg/day.
SuppsBuddy checks that iodine dose sits within the 150–500 mcg range and flags kelp-based products that cannot reliably confirm per-serving content. Products significantly exceeding the RDA without clinical context receive reduced scores.
Frequently asked questions
What is Iodine?
Iodine is an essential trace mineral required exclusively for the synthesis of thyroid hormones T3 (triiodothyronine) and T4 (thyroxine). It is one of the most widespread micronutrient deficiencies worldwide despite being readily available through iodized salt and seafood. Subclinical deficiency is common, particularly in pregnant women and populations avoiding processed foods.
How does Iodine work?
The thyroid gland concentrates iodine from the bloodstream and incorporates it into thyroglobulin via thyroid peroxidase enzyme activity. The resulting thyroid hormones regulate basal metabolic rate, thermogenesis, protein synthesis, and neurological development — making iodine indirectly critical to energy, cognition, and weight management.
What is the typical clinical dose range for Iodine?
150–300 mcg/day. RDA: 150 mcg/day for adults; 220 mcg for pregnancy; 290 mcg for lactation. Most supplements provide 150–250 mcg. The UL is 1,100 mcg/day. High-dose iodine supplements (mg range) require medical supervision.
What forms of Iodine should I look for?
Potassium Iodide: Most common pharmaceutical grade; well absorbed and stable | Sodium Iodide: Equivalent bioavailability to potassium iodide | Kelp / Seaweed Extract: Natural source but iodine content varies significantly by batch | Molecular Iodine (I2): Some evidence for specific applications; less common in supplements
Is Iodine safe?
Excess iodine can paradoxically inhibit thyroid function (Wolff-Chaikoff effect). Individuals with autoimmune thyroid disease (Hashimoto's, Graves') should consult a physician before supplementing. The UL is 1,100 mcg/day. This information is educational and is not medical advice.
How does SuppsBuddy evaluate Iodine?
SuppsBuddy checks that iodine dose sits within the 150–500 mcg range and flags kelp-based products that cannot reliably confirm per-serving content. Products significantly exceeding the RDA without clinical context receive reduced scores.
Related ingredients
This page is for educational purposes only. These statements have not been evaluated by the FDA. This information is not intended to diagnose, treat, cure, or prevent any disease. Always consult a qualified healthcare professional before starting any supplement.