Iodine is an essential trace mineral required for the synthesis of thyroid hormones (T3 and T4). These hormones are master regulators of systemic metabolism, impacting everything from body temperature and heart rate to cellular energy production. Maintaining iodine sufficiency is therefore foundational for metabolic health and cognitive function, but there is no evidence that supra-physiological doses extend healthspan.
Verdict
Ensure sufficiency via diet or RDA-level supplement; avoid unproven high doses.
HEALTHSPAN IMPACT
Moderate
RISK LEVEL
Low
EVIDENCE GRADE
A
MONTHLY COST
$5 - $20
Protocol
- Supplement with 150-250 mcg daily, often as potassium iodide, to meet or slightly exceed the RDA.
- Ensure adequate intake through iodized salt or iodine-rich foods like seaweed and seafood.
Flags
- Excess iodine intake can induce or worsen both hypothyroidism and hyperthyroidism.
- Individuals with autoimmune thyroid conditions (e.g., Hashimoto's) can be highly sensitive to iodine.
- May interact with anti-thyroid medications, ACE inhibitors, and potassium-sparing diuretics.
- Testing urinary iodine concentration is advisable before considering supplementation beyond the RDA.