Freedom or Folly?

In August 2025, the Madras High Court struck down the ban on the sale of non-iodised salt for direct human consumption, citing procedural lapses and the primacy of individual choice and commercial freedom. While the ruling appears to uphold personal liberty, it endangers one of India’s most impactful public health achievements: universal salt iodisation (USI). This decision risks reversing decades of progress in combating iodine deficiency disorders (IDD), particularly among the most vulnerable populations. As India stands at the forefront of global efforts to eliminate IDD, such a step backwards could not only undermine national health gains but also weaken the country’s position as a leader in this critical public health domain.

India’s fight against iodine deficiency began in 1962 with the National Goitre Control Programme, initially targeting specific high-prevalence areas. As evidence of widespread iodine deficiency across the country mounted, the programme evolved into the National Iodine Deficiency Disorders Control Programme (NIDDCP). By 1992, India mandated iodisation of all edible salt, a cost-effective measure that significantly reduced goitre prevalence and improved cognitive outcomes nationwide. This policy positioned India as a global leader in tackling IDD, with the country becoming one of the largest producers of iodised salt and achieving household coverage rates exceeding 90% in recent surveys.

The success of India’s iodisation efforts must be viewed within the broader global context, where salt iodisation has emerged as one of the most remarkable public health achievements of the past three decades. According to the Iodine Global Network (IGN), a key international body dedicated to eliminating IDD, access to adequately iodised salt has surged dramatically since the early 1990s. In 1990, only about 20% of the global population had access to iodised salt. By 2022, this figure had risen to an impressive 88%. This progress has been driven by concerted efforts from governments, international organisations, and the salt industry, resulting in the prevention of millions of cases of cognitive impairment and other IDD-related conditions.

Globally, the World Health Organisation (WHO) has long endorsed universal salt iodisation as the preferred, safe, and effective strategy to address iodine deficiency. WHO guidelines recommend fortifying all food-grade salt with iodine at levels of 20-40 mg/kg, including salt used in households, food processing, and livestock feed. This approach ensures broad population coverage without relying on individual behaviour changes. The impact has been profound: over 130 out of 197 countries now have mandatory legislation for salt iodisation, leading to major health and economic benefits. Studies highlight that improved iodine nutrition has boosted IQ levels by up to 13 points in deficient populations, enhancing productivity and reducing healthcare costs associated with IDD.

India has been at the forefront of these global triumphs. As a founding member of the IGN and a major player in the international salt trade, India has not only achieved near-universal coverage domestically but has also exported iodised salt to neighbouring countries, supporting regional efforts. The India Iodine Survey 2018-19 showed that over 55% of respondents were aware of iodised salt, with higher awareness in urban areas, underscoring the programme’s reach. However, challenges persist, such as ensuring consistent iodisation in small-scale production and addressing price sensitivities among low-income groups. India’s robust infrastructure and policy framework have served as a model for other developing nations, demonstrating how political commitment can translate into tangible health outcomes.

Despite these successes, India’s own history reveals the fragility of such gains. A policy reversal in 2000, when the ban on non-iodised salt was briefly lifted in favour of voluntary iodisation, exposed this vulnerability. The District Level Household Survey (DLHS-2, 2002–04) reported a sharp decline in iodised salt coverage, dropping from over 50% nationally to just 30%. In states like Uttar Pradesh and Bihar, coverage fell to 18% and 17%, respectively. The poorest households, least aware of iodine’s importance and most sensitive to price differences, were hit hardest. The government reinstated the ban in 2005, and by the National Family Health Survey (NFHS-3, 2005–06), iodised salt coverage had largely recovered. Subsequent surveys, including NFHS-5 (2019-21), indicate coverage above 90%, aligning with global benchmarks set by WHO and IGN.

The recent Madras High Court ruling threatens to repeat the earlier mistake. It overlooks the public health necessity of mandatory iodisation. Iodised salt is a “merit good”—its benefits are not immediately obvious, and consumers may undervalue it. Left to market forces, iodised salt will not reach the most disadvantaged, deepening health inequities. Globally, IGN warns that lapses in enforcement can lead to a resurgence of IDD, as seen in some regions where coverage has dipped below 90%.

Iodine deficiency impairs cognitive development, lowers IQ, and reduces productivity, with irreversible, intergenerational consequences. WHO estimates that IDD affects nearly 1.9 billion people worldwide, though this number has declined significantly due to USI. In India, with its young demographic, compromising cognitive capacity is counterproductive to harnessing the demographic dividend. The economic toll is staggering: studies cited by IGN suggest that iodine deficiency can reduce a country’s GDP by up to 1%, through lost productivity and increased healthcare burdens. The argument for consumer choice must be weighed against these societal costs: preventable cognitive impairments strain public health systems, hamper workforce productivity, and undermine national progress.

Mandatory salt iodisation is not about restricting freedom but about ensuring equity. It guarantees that even the most marginalised have access to a fundamental safeguard against IDD, akin to clean water or vaccinations. With India’s production capacity and iodisation infrastructure, the challenge is not technical but political and awareness-related.

To protect this public health success, urgent steps are needed. First, the government must appeal the Madras High Court’s ruling and reaffirm a national mandate for iodised salt, aligning with WHO’s USI guidelines. Second, targeted awareness campaigns, especially in rural and underserved areas, should underscore iodine’s role in health and development. Third, stringent enforcement across the salt supply chain must ensure compliance from production to retail, including regular monitoring. Additionally, integrating iodine nutrition into broader health initiatives, such as maternal and child health programs, can amplify impact.

India’s progress in reducing iodine deficiency showcases the power of evidence-based policy, mirroring global achievements where USI has prevented an estimated 750 million cases of goitre since 1990. Yet, this achievement remains vulnerable and requires steadfast protection.

Let us not jeopardise the cognitive potential of our children or the hard-won global gains in iodine nutrition. India must uphold the science, ethics, and legacy of its salt iodisation programme. The stakes—for individuals, society, and the nation—are too high for complacency.

Views expressed are personal