Iodised Salt

A double-edged ingredient: 29% of the world's population remains iodine-insufficient, yet excess sodium drives hypertension and bone loss. The goal is enough iodine from as little salt as possible.

Why It Matters for Longevity

Iodine is the rate-limiting substrate for thyroid hormones T3 and T4, which regulate metabolism, body temperature, and -- critically during pregnancy -- brain development. Mild iodine deficiency in pregnant and breastfeeding women impairs neuronal migration, myelination, and synaptogenesis in the developing brain, potentially reducing IQ and increasing ADHD risk. WHO reports (Zimmermann & Boelaert, 2015) found 29% of the global population remains iodine-insufficient, including populations in developed nations.

The tension is real: reducing salt to <5g/day (WHO target) lowers blood pressure and cardiovascular events, but eliminating salt entirely risks iodine deficiency unless alternative sources are secured. Each 2.3g of sodium consumed increases urinary calcium excretion by approximately 40mg (Cappuccio & Campbell, 2017), contributing to bone loss -- particularly problematic for postmenopausal women already at osteoporosis risk.

The solution: use iodised salt as your sole home salt source (~5g/day provides 150mcg iodine, 100% RDA), supplement with iodine-rich foods (dried seaweed: 65-680mcg/100g; marine seafood: 50-100mcg/100g), and use herbs, spices, garlic, and lemon juice to add flavor complexity that reduces dependence on salt quantity.

How to Use It

~5g iodised salt per day as your sole salt source. If reducing salt below this, supplement iodine from seaweed, seafood, or small amounts of dairy. Store sealed to prevent iodine loss from humidity. Use herbs, spices, and acid (lemon, vinegar) to reduce salt needs.

What to Pair It With

Flavor Profile

Pure salinity with mineral notes. Iodised salt has a faintly metallic aftertaste that some detect. Fine-grain dissolves instantly; coarse provides finishing texture. The flavor contribution is enhancement of other ingredients rather than its own distinct taste.

The Science

• WHO: reducing sodium to <5g salt/day significantly lowers BP and CV events (Aburto et al., 2013)
• 29% of world population iodine-insufficient; pregnancy deficiency impairs child brain development (Zimmermann & Boelaert, 2015)
• High sodium increases urinary calcium excretion ~40mg per 2.3g sodium (Cappuccio & Campbell, 2017)
• 5g iodised salt/day provides ~150mcg iodine (100% RDA)
• Thyroid hormones T3/T4 require iodine for synthesis; deficiency affects metabolism and cognition

Key Nutrients