Iodised Salt: FSSAI's 15-30 ppm Standard and WHO's 5 g Salt Limit

A non-metal with several different chemical forms

Iodine has the chemical symbol I and atomic number 53. It belongs to group 17 of the periodic table, the halogens. Pure iodine is a dark, shiny solid at ordinary room temperature, despite being a non-metal. It can form a violet vapour through sublimation, a change directly from solid to gas. The shine does not make it a metal. Equally, its striking laboratory appearance should not be confused with the appearance or safety of iodine-containing foods.

The element and its compounds are not interchangeable products. Iodide and iodate are chemical forms in which iodine occurs in salts. A regulated food fortificant supplies the nutrient in a suitable compound and concentration. It does not turn ordinary white salt into a pile of purple iodine crystals. This distinction matters because chemical identity, formulation and quantity determine how a substance is used. A disinfectant containing iodine is not thereby a food supplement, just as nutritional salt is not a medicine.

The link between a tiny nutrient and the thyroid

The thyroid uses iodine to produce thyroxine, called T4, and triiodothyronine, called T3. These hormones help control how the body uses energy. They are also important for skeletal and nervous-system development. A small nutritional requirement can therefore have consequences far beyond the quantity involved. During pregnancy and early childhood, inadequate iodine can interfere with development at a particularly sensitive stage. The public-health concern is not restricted to a visible swelling in the neck; it includes effects that are less immediately apparent.

Food sources include fish and other seafood, eggs and dairy products, but iodine content varies. Seaweed can contain especially variable amounts. A food's name alone does not establish an individual's intake, and sea salt or specialty salt is not automatically iodised. Excessive iodine intake can also disturb thyroid function, including causing underactivity or overactivity in susceptible people. A high-dose supplement is therefore not simply a stronger version of healthy food. Individual supplementation and thyroid treatment require appropriate clinical advice, rather than being inferred from a general awareness message.

Why salt became a public-health vehicle

Fortification means adding a small amount of a necessary nutrient to a food. Salt iodisation uses this approach to improve iodine intake through an established food supply, instead of relying only on people identifying a deficiency themselves. The World Health Organization recommends iodising food-grade salt used both in households and in food processing. The intention is to reach the population through the salt already consumed, not to create demand for larger portions. Consistent production, distribution and quality checks are therefore central to the approach.

Salt reduction and iodine fortification need to be planned together. If people consume less salt, the amount of iodine reaching them through that vehicle can also change. The answer is not to abandon sodium reduction. Health authorities can adjust the fortification programme and monitor iodine status as consumption patterns change. Two measurements then serve different purposes: how much salt people consume, and whether they receive adequate iodine. Treating either measurement as a substitute for the other would miss part of the health problem.

Less sodium does not mean neglecting iodine

The World Health Organization recommends that adults consume less than 2,000 milligrams of sodium daily, equivalent to less than 5 grams of salt. This concerns the whole diet, not an extra allowance to sprinkle over meals. Sodium also comes from prepared foods, sauces and condiments. Excess sodium raises blood pressure and increases cardiovascular risks. Recommendations for children need adjustment for their circumstances and energy needs; the adult figure is not a universal allowance for every age. Choosing iodised salt within a lower-salt diet addresses nutrient quality without ignoring the amount consumed.

A concentration standard is not a daily dose

The Food Safety and Standards Authority of India's published February 2022 compendium lists potassium iodate as the iodine source for iodised salt. Its table specifies 15–30 parts per million on a dry-weight basis. This is a product-concentration specification in that dated document, not a new October 2026 announcement. For a mass concentration, one part per million corresponds to one milligram per kilogram. The unit describes how much iodine is present in salt; it does not prescribe how much salt a person should eat.

This is why food quality and personal intake are different questions. A compliant concentration cannot, by itself, establish that every person obtains the right amount of iodine. Intake also depends on how much of that food is consumed and on other dietary sources. Conversely, eating more salt is not an appropriate way to compensate for uncertain product quality. Public-health monitoring needs to follow the fortified food through the supply chain and examine nutritional outcomes. An awareness campaign alone cannot establish adequate intake.

India's programme looks beyond visible goitre

India began the National Goitre Control Programme in 1962. In 1992, it was broadened and renamed the National Iodine Deficiency Disorders Control Programme. The Health Ministry's 2024 account explains that the wider programme includes surveys, salt-quality testing, urinary iodine monitoring and public education. The change in scope reflects the fact that iodine deficiency is not only a problem of an enlarged thyroid, or goitre. Preventing developmental harm and maintaining adequate nutrition require attention before a visible sign prompts an individual to seek care.

Urinary iodine is useful because much of the iodine absorbed is eventually excreted in urine. Population surveys commonly use the median concentration to assess a group's iodine status. That is not the same as diagnosing one person from one spot sample. Interpretation also differs between groups, including pregnant women and school-age children. A population indicator, a test of salt concentration and an individual clinical assessment answer different questions. Keeping their scope clear prevents a reassuring national figure from being treated as evidence about every household or patient.

The same element also has an industrial geography

Iodine's importance extends beyond nutrition. The United States Geological Survey's 2026 review identifies Chilean desert nitrate deposits and Japanese gas and oil fields as major supply areas. It also identifies northwestern Oklahoma's brines. Brine is water containing high concentrations of dissolved salts. Commercial recovery therefore depends on accessible deposits and processing conditions, not simply on iodine's presence in the oceans. The survey identifies uses including medical X-ray contrast agents, liquid-crystal displays, pharmaceuticals and disinfectant formulations. These applications involve specific compounds and controlled processes; they do not make industrial products substitutes for nutritional iodine.

Conclusion

The ministry's message brings together two compatible goals: enough iodine and less excess salt. Effective prevention requires reliable fortification, access to suitable food and monitoring that distinguishes population nutrition from individual care. The choice is not between avoiding iodine and eating more salt. It is to obtain an essential nutrient through appropriate foods while keeping total sodium intake under control. Awareness helps, but sustained quality and nutritional surveillance determine whether that advice produces its intended public-health benefit.