Context: The fifth National Family Health Survey (NFHS-5) found that more than half of Indian women and about two-thirds of young children are anaemic.
- Double-Fortified Salt (DFS), fortified with iodine and iron, is proposed as a convenient intervention to tackle anaemia, but its effectiveness and potential health risks require scrutiny.
Concerns Associated with Double-Fortified Salt (DFS)
- Conflict with salt-reduction goals: Indians consume nearly twice the World Health Organization (WHO) recommended limit of 5 grams of salt per day. With around one-third of adults suffering from hypertension, India aims for a 30% relative reduction in salt intake under its Non-Communicable Disease (NCD) action plan. DFS may indirectly encourage continued salt consumption.
- Unequal iron delivery: Salt consumption varies by age, sex and region. Adult men generally consume more salt, while women and young children consume less, potentially delivering lower iron doses to groups with greater anaemia vulnerability.
- Convenience does not ensure efficacy: Reducing salt intake also reduces iron intake through DFS. Its effectiveness depends on regular salt consumption, creating a conflict with sodium-reduction objectives.
Potential Health Risks of Excess Iron
- Iron accumulation: Unlike several other nutrients, the human body has no regulated mechanism to excrete excess iron. Accumulation can cause oxidative stress and is associated with metabolic disorders.
- Evidence from clinical trials:
- 2006 Pemba trial, Tanzania: Iron and folic acid supplementation among children in a malaria-endemic setting was associated with increased hospitalisations and deaths.
- 2015 Kenyan trial: Iron-fortified foods altered infants' gut microbiota towards pathogenic bacteria and increased diarrhoea.
- Relevance to India: Large malaria-endemic and poorly sanitised regions increase concerns regarding indiscriminate iron supplementation and fortification.
Risks for People with Haemoglobinopathies
- Beta-thalassaemia: Millions of Indians carry beta-thalassaemia, a genetic disorder affecting haemoglobin production.
- Sickle Cell Disease (SCD): Prevalent particularly in India's tribal belts.
- Iron overload: People with thalassaemia, particularly those receiving repeated blood transfusions, are vulnerable to iron accumulation.
- Implementation challenge: Screening the approximately 800 million beneficiaries of the Public Distribution System (PDS) before DFS consumption is practically unfeasible.
Cumulative Iron Exposure Through Government Programmes
- Existing interventions: Iron is already delivered through fortified rice distributed under:
- Public Distribution System (PDS).
- Pradhan Mantri Poshan Shakti Nirman (PM POSHAN).
- Integrated Child Development Services (ICDS).
- Iron-Folic Acid (IFA) supplementation programmes for vulnerable groups.
- Risk of overlapping exposure: Children and adolescents may receive iron through three or four government interventions simultaneously.
- Policy gap: No adequate published assessment of cumulative iron intake across these programmes exists. Introducing DFS as a national flagship intervention without such an assessment may be premature.
Factors Affecting Iron Absorption from DFS
- Non-haem iron: DFS contains non-haem iron, whose absorption depends heavily on dietary composition.
- Dietary inhibitors: Phytates in cereals, millets and pulses bind iron; polyphenols in tea and coffee and calcium in milk further reduce its absorption.
- Limited bioavailability: Iron absorption from typical Indian meals is relatively low compared with haem iron or iron consumed with vitamin C.
- Gut microbiota concerns: Since DFS is consumed with food, much of its iron may remain unabsorbed and reach the colon, potentially promoting pathogenic gut microbes.
- Variable effectiveness: Household cooking losses, uneven dosing and dietary variations can reduce effectiveness compared with supervised efficacy trials.
- Effect of infections: The hormone hepcidin, which regulates iron metabolism, blocks iron absorption during infection and inflammation. Thus, fortification may be least effective in populations with high infection burdens.
Anaemia Is Not Synonymous with Iron Deficiency
- Global evidence: Approximately half of global anaemia cases are attributed to iron deficiency.
- Indian evidence: The Comprehensive National Nutrition Survey (2016–18) found that iron deficiency explained only a part of anaemia among Indian children and adolescents.
- Other causes of anaemia:
- Nutritional deficiencies: Folate, vitamin B12, protein and vitamin A deficiencies.
- Infections and diseases: Chronic inflammation, recurrent infections, hookworm and malaria.
- Genetic factors: Haemoglobinopathies such as thalassaemia and sickle cell disease.
- Socio-economic factors: Poor sanitation, overall undernutrition, early marriage, adolescent pregnancy and menstrual blood loss.
- Measurement concerns: Capillary haemoglobin measurements and the diagnostic cut-offs used can influence reported anaemia prevalence.
Limitations of India's Existing Anaemia Strategy
- Multi-causal nature: Anaemia requires interventions addressing nutritional deficiencies, infections, sanitation and genetic conditions rather than iron alone.
- 7x7x7 approach: India's revised anaemia strategy deserves credit for incorporating multiple interventions beyond conventional iron supplementation.
- IFA dependence: The programme continues to rely heavily on iron-folic acid tablets despite compliance challenges and gastrointestinal side effects.
- Diagnostic limitations: Haemoglobin testing alone cannot establish the cause of anaemia. Routine testing for ferritin, vitamin B12 and inflammatory markers remains limited.
- Dietary affordability: The 'Eat Right' approach needs to address affordability and access to diverse foods such as eggs, dairy, green vegetables and millets.
- Weak outcome monitoring: Digital tracking often focuses on the number of tests and tablets distributed rather than actual health outcomes.
- Neglected interventions: Deworming, malaria control and Water, Sanitation and Hygiene (WASH) interventions remain insufficiently prioritised.
- Risk of policy reversal: Making DFS a flagship intervention could revive the single-nutrient approach that the 7x7x7 framework seeks to overcome.
International Experiences in Tackling Anaemia
- Peru:
- Reduced child anaemia by double digits in the early 2010s.
- Made anaemia a political priority, tracked children individually through health contacts and combined iron supplements and micronutrient powders with cash transfers.
- Held regional administrations accountable for outcomes.
- Progress reversed after COVID-19 disrupted service delivery, highlighting the importance of sustained implementation.
- Vietnam:
- Reduced anaemia among women through weekly IFA supplementation, deworming and fortified fish sauce.
- Used Sodium Iron Ethylenediaminetetraacetate (NaFeEDTA), a form of iron with better bioavailability in phytate-rich diets.
- Improvements were accompanied by rising incomes and greater dietary diversity.
- Key lesson: Neither country relied on a single fortified food. Their success involved context-specific interventions alongside improvements in healthcare delivery and nutrition.
Way Forward
- Monitored district-level pilots: Test DFS before national expansion, measuring haemoglobin, ferritin and inflammation markers and assessing cumulative iron exposure.
- Risk assessment: Monitor potential adverse effects, particularly in malaria-endemic and haemoglobinopathy-prone regions.
- Targeted fortification: Prefer targeted interventions over universal fortification and use better-absorbed iron formulations suited to local dietary patterns.
- Strengthen diagnostics: Identify the underlying causes of anaemia through appropriate nutritional and clinical investigations.
- Integrated interventions: Strengthen deworming, malaria control, sanitation and access to affordable, diverse diets.
- Outcome-based monitoring: Evaluate improvements in health outcomes rather than merely counting supplements, tests and fortified food distribution.
Conclusion: Anaemia is a multi-causal public health challenge. India needs an integrated nutrition, healthcare and sanitation strategy rather than relying on a single-nutrient intervention such as iron-fortified salt.
