Vitamins and Minerals: Vitamin Deficiency Diseases, Malnutrition and Nutrition Programmes

Vitamin Deficiency Diseases and Mineral Deficiencies

Micronutrients: Why Milligrams Decide Health Outcomes

A micronutrient is a vitamin or a mineral the body needs in milligrams or micrograms rather than grams. It supplies no energy at all, which is what separates it from the macronutrients set out in Part 1, on digestion and the macronutrients.

A shortage measured in milligrams produces a named disease, while the same diet may carry enough energy to leave body weight normal. A person can therefore be adequately fed and seriously deficient at once, which is why nutrition policy measures more than calories.

Worldwide, more than half of children under five, and over two-thirds of non-pregnant women of reproductive age, are deficient in at least one key micronutrient, most often iron, with effects that run from anaemia and scurvy through to cognitive impairment and neural tube defects.

Vitamins divide by one property before any other, which is what they dissolve in:

• Fat-soluble vitamins, namely A, D, E and K, are stored in the body. A shortage takes months to show, and an excess can accumulate to the point of harm.
• Water-soluble vitamins, the B group and C, are not stored in any quantity. They have to arrive regularly, and a surplus is largely excreted.

Fat-Soluble Vitamins A, D, E and K and Their Deficiency Diseases

The four vitamins that dissolve in fat travel with dietary fat and are stored in the liver and fatty tissue. That storage is why a deficiency develops slowly, and why an excess can accumulate, which is not a practical risk with the water-soluble group.

Vitamin A, whose circulating form is retinol, has the best-known deficiency. Xerophthalmia is the name for the whole clinical spectrum of eye changes that vitamin A deficiency produces, running from night blindness and Bitot spots through to corneal ulceration and keratomalacia.

Night blindness, the difficulty of seeing in low light, is the mildest of those stages and the earliest clinical sign. It is common in pregnancy in developing countries, which is why supplementation programmes target pregnant women and young children rather than the population at large.

The eye is where this deficiency declares itself, and the sequence runs one way. Only the first two stages can be undone; after that the damage to the cornea is permanent:

• Night blindness, difficulty seeing in low light, which is the earliest clinical sign and is reversible.
• Bitot spots, foamy patches on the conjunctiva, still reversible with treatment.
• Corneal xerosis and ulceration, as the cornea dries and breaks down.
• Keratomalacia, the softening and destruction of the cornea, which is not reversible and leaves the child blind.

The plant precursor needs care. Carotene is not vitamin A itself but has provitamin A activity, which the body converts, so carotene belongs to the category vitamin while retinol is vitamin A itself.

Vitamin D is a calciferol, and its shortage in children produces rickets, a condition of weak or soft bones with bowed legs and stunted growth. Vitamin E is a group of eight related compounds, four tocopherols and four tocotrienols, and vitamin K exists as two natural vitamers, both required for blood coagulation.

Water-Soluble Vitamins B and C and Their Deficiency Diseases

The water-soluble vitamins are not stored, so their deficiencies appear faster and respond faster to correction. Each of the classical deficiency diseases below is named against the vitamin whose absence produces it.

• Thiamine, vitamin B1, is the one whose severe chronic deficiency is called beriberi. Wet beriberi affects the cardiovascular system, producing a fast heart rate, breathlessness and swelling of the legs; dry beriberi affects the nerves. The risk rises on a diet of mostly polished white rice.
• Niacin, vitamin B3, is the vitamin whose lack causes pellagra.
• Folate, vitamin B9, and cobalamin, vitamin B12, both produce anaemia when short. Folate shortage in early pregnancy is also associated with neural tube defects.
• Ascorbic acid, vitamin C, is the one whose deficiency is scurvy, a deficiency disease and a state of malnutrition that results from a lack of vitamin C.

A vitamin, an enzyme and a hormone are three different categories of molecule: carotene is a vitamin precursor, pepsin an enzyme and progesterone a hormone. That classification is set out in Part 1, in the section on digestive enzymes.

The B vitamins also work as coenzymes rather than as structural material. Niacin is the essential chemical component of the coenzymes NAD and NADP, which take part in a great many enzyme-catalysed reactions, so a shortage affects metabolism across the whole body rather than one organ.

Iron and Calcium: The Two Minerals Most Often Short

Minerals differ from vitamins in being elements rather than organic compounds, so no organism can synthesise them and they must come from soil, water or food. Two account for most of the deficiency burden the national surveys measure, and a third is dealt with separately below.

Iron is required to build haemoglobin, and its shortage is the commonest cause of anaemia. The National Family Health Survey puts it at 67.1 per cent of children and 59.1 per cent of adolescent girls, and three in four women have a low dietary iron intake.

Those figures place anaemia among the most widespread nutritional conditions measured anywhere. The dietary sources of iron are pulses, dark green leafy vegetables and millets, with pearl millet carrying 16.9 milligrams per 100 grams and barnyard millet 15.2.

Prevalence and priority are not the same. Xerophthalmia, the vitamin A deficiency, has a claim to priority for remedial action because its end stage is irreversible blindness in a child. Anaemia is commoner; blindness is worse.

Calcium builds and maintains bone and works with vitamin D, which is why the two deficiencies present together. Among cereal grains finger millet, or ragi, stands far above the rest at 344 milligrams per 100 grams, while polished rice carries almost none, a contrast developed in the article on millets in agriculture.

Milk is the other familiar source, and what it lacks matters as much as what it has. Besides protein and carbohydrate it supplies calcium and potassium in useful quantity, but it is a poor source of iron, which is why a milk-heavy diet can leave a child well grown and still anaemic.

Iodine, Thyroxine and the Case for Salt Iodisation

Iodine occupies a category of its own because its entire nutritional role runs through two molecules. It is an essential trace element present in the thyroid hormones, thyroxine and triiodothyronine, and that is the whole of why the body requires it.

The hormone that contains iodine is therefore thyroxine. The deficiency is geographical rather than dietary in origin: it occurs most often where there is little iodine in the diet, typically remote inland areas where no marine foods are eaten.

Measurement has shifted away from the visible sign. The median urinary iodine concentration is now the main indicator of iodine status for all age groups, because assessment of goitre by palpation or ultrasound becomes difficult to interpret once salt iodisation programmes have begun.

The policy answer is to iodise the one commodity almost everyone consumes. Salt carries 15 to 30 parts per million of iodine, a level the regulator amended in 2021 from the earlier 20 to 30, and coverage now reaches almost every household with young children.

Malnutrition in India and How It Is Measured

The Four Forms Malnutrition Takes, Counted Together

Malnutrition is not a synonym for hunger. As the World Health Organization defines it, it covers undernutrition, meaning wasting, stunting and underweight; inadequate vitamins or minerals; overweight and obesity; and the diet-related noncommunicable diseases that follow.

So overnutrition, undernutrition and an imbalanced diet all count as malnutrition, and reading it as a shortage of food alone is a mistake.

The scale of each is now comparable. In 2022, among children under five, 149 million were stunted, 45 million wasted and 37 million overweight. Among adults, 2.5 billion were overweight including 890 million living with obesity, against 390 million underweight.

The fourth form follows from the other three rather than sitting beside them. Heart disease, stroke, type 2 diabetes and some cancers are consequences of the diet that produced the first three, which is why a nutrition policy and a public health policy cannot sensibly be written apart.

Stunting, Wasting and Underweight: What Each One Measures

The three indicators of child undernutrition are used interchangeably in ordinary speech and mean quite different things. Each compares a child against a reference population on a different pair of measurements, and each tells a different story about when the deprivation happened.

The first of the three measures linear growth retardation and cumulative deficit, so stunting reflects deprivation sustained over months or years. Wasting reflects a recent and acute shortfall, which is why it can rise sharply in a drought or an epidemic and fall again when conditions improve.

The direction of travel is modestly favourable. Stunting fell from 38 per cent in the 2015 to 2016 round to 36 per cent in the latest, and underweight has also declined. Progress of two percentage points across a national round is real but slow against the size of the problem.

The distribution matters more than the average. Stunting runs at 46 per cent among children in the lowest wealth quintile against 23 per cent in the highest, and children born to mothers with no schooling are most likely to be undernourished, which is what makes this a question of equity and not only of food.

Protein-Energy Malnutrition: Marasmus and Kwashiorkor

Protein-energy malnutrition (PEM) is the severe end of undernutrition: a lack of dietary protein, of energy (calories), or of both, in varying proportions. It takes three clinical forms. Marasmus is a shortage of energy from all sources, protein included, which can cut body weight below 62 per cent of the expected weight for the age; kwashiorkor is mainly a shortage of protein, often with enough calories; and a child showing signs of both has marasmic kwashiorkor, sometimes described as the most severe form of malnutrition.

The name of kwashiorkor explains its cause. The Jamaican paediatrician Cicely Williams first described it formally in 1933 and named it in 1935, from the Ga language of coastal Ghana. It develops in an older child weaned from the breast when a younger sibling arrives, and moved to a diet high in carbohydrates such as maize, cassava or rice, which lacks the amino acids that breast milk supplied.

Marasmus and kwashiorkor together make up severe acute malnutrition (SAM). Under the WHO and UNICEF criteria of 2009, a child aged 6 to 60 months has SAM if any one of three independent signs is present:

1. Weight-for-height below minus 3 standard deviations of the WHO child growth standards, that is, severe wasting.
2. A mid-upper arm circumference (MUAC) below 115 mm; the cut-off was raised from 110 mm in 2009.
3. Bilateral oedema, the clinical sign of kwashiorkor.

In India the extreme forms are now rare. The national Dietary Guidelines for Indians of 2024 note that marasmus, kwashiorkor and keratomalacia have largely disappeared, while milder undernutrition and anaemia persist alongside rising overweight and obesity, a dual burden of malnutrition. Treating severe and moderate acute malnutrition (SAM and MAM) is one of the stated focuses of Poshan 2.0.

Anaemia and the 6X6X6 Strategy Built Against It

Anaemia is defined by a haemoglobin concentration below a threshold. It is the most prevalent nutritional condition the national survey measures, at 67.1 per cent of children, and the response to it is the most fully specified nutrition programme the country runs.

The strategy is named 6X6X6 because it has three arms of six: six target beneficiary groups, six interventions and six institutional mechanisms. Two of the six interventions are easy to miss.

The behaviour change campaign carries delayed cord clamping inside it, by three minutes after delivery in health facilities. That is an intervention against anaemia that involves no supplement and no food at all, which makes it easy to overlook.

The sixth intervention addresses causes that are not nutritional. It names malaria, haemoglobinopathies and fluorosis by name, in recognition that anaemia in an endemic pocket may have nothing to do with iron intake, and that supplementation alone will not move it.

Two further interventions complete the set: deworming, since intestinal parasites cause blood loss, and the mandatory provision of iron and folic acid fortified foods in government-funded health programmes, which connects this strategy to the fortification standards in the next section.

Global Hunger Index: Its Indicators and the Dispute Over It

The Global Hunger Index is a composite score published annually, computed by the International Food Policy Research Institute and released with two European organisations. India's position in it is contested by the Government, so both its composition and the objection matter.

The index rests on four indicators: undernourishment, child stunting, child wasting and child mortality. Three of the four are measures of child health, and only the first is a direct measure of insufficient food intake across the population as a whole.

That composition is the basis of the objection. The Government has argued that the measure does not reflect the true picture because only one of its four indicators is directly related to hunger, while the other three turn on child health outcomes that depend on sanitation, infection and maternal health as much as on food.

Knowing that three of the four indicators are child-health measures explains both what the index contains and why its ranking is disputed, without taking a side.

Fortification, Biofortification and the Safety of Food

Food Fortification: Five Commodities and the Plus-F Mark

Adding a nutrient to a food during processing, in quantities set by regulation, is fortification. It reaches people through what they already eat rather than by asking them to change what they choose, which is what makes it effective against a deficiency that is widespread and quiet.

Five commodities carry a standard: wheat flour and rice with iron, folic acid and vitamin B12; edible oil and milk with vitamins A and D; and double fortified salt, which carries iron in addition to the iodine that ordinary iodised salt already has.

The declaration is made by a mark rather than a certificate. A food business that fortifies any of these commodities must carry the plus-F mark on the pack, a plus sign beside the letter F, and the procedure runs on self-compliance, which puts the obligation on the business and the verification on enforcement rather than on prior approval.

Iodised salt is the oldest and most complete of these programmes, carrying 15 to 30 parts per million of iodine since the 2021 amendment. Its near-universal reach among households with young children is the benchmark against which the newer fortification standards are measured.

Biofortification: Breeding the Nutrient Into the Crop Itself

Biofortification differs from fortification in where the nutrient enters. Fortification adds it to a processed food; biofortification breeds or engineers it into the growing crop, so the nutrient is present in the grain as harvested and survives without any processing step.

The consequence is a difference in reach. A fortified food depends on a processing industry and a distribution chain, so it can miss a household that mills its own grain. A biofortified crop carries the nutrient wherever the seed is sown, which suits the smallholder context where deficiency is worst.

Golden rice is the standard example: a vitamin A enriched rice, developed for the nutritional value of its grain. The engineered trait is vitamin A, not yield, not pest resistance and not drought tolerance.

The route is genetic rather than agronomic in that case, which places golden rice inside the wider debate over genetically modified crops. Conventional breeding achieves the same end in other crops, so biofortification is not always genetic modification.

Food Safety: Aflatoxins, Probiotics and the Regulator

Food can carry risk as well as nutrition, and two categories stand out. One arises from how food is stored, the other from what is deliberately added to it.

The first category is produced by moulds, which are fungi, growing on cereal grains and oilseeds that have been handled or stored improperly. These aflatoxins are a storage failure rather than a cultivation failure, they survive normal cooking, and the remedy is drying and handling rather than anything done in the field.

The second category is added on purpose. A probiotic is a live microorganism intended to support or improve the health of the host that consumes it, and two points in that definition matter: the organisms must be live, and they include yeasts as well as bacteria, which is why yoghurt, cheese and fermented foods all serve as vehicles.

These organisms also occur naturally in the gut. The gut carries its own microbiota, which is precisely what a probiotic is intended to manipulate, so a statement confining the organisms to ingested food is false.

• Aflatoxins are a contaminant. They arise from storage failure, survive normal cooking, and are prevented by drying and handling rather than treated afterwards.
• Probiotics are a deliberate addition. They must be live, they include yeasts as well as bacteria, and they act on a gut microbiota that is already there.

Standards for all of this sit with the Food Safety and Standards Authority, which sets the fortification levels above, the trans fat ceiling discussed in Part 1, on fats in the diet, and the prohibitions that govern what may be sold. Its instrument is the regulation, and its mode is the numerical limit rather than the advisory.

The Programmes That Deliver Nutrition, and Their Legal Basis

National Food Security Act, 2013 and Its Entitlements

The National Food Security Act, 2013 received assent on 10 September 2013 as Act No. 20 of 2013. Its significance is that it converted a set of welfare schemes into legal entitlements, so that what had been a benefit administrators could adjust became a right a person could claim.

The quantities are written into the statute. A priority household receives five kilograms of foodgrains per person per month at subsidised prices, while a household covered by the Antyodaya Anna Yojana receives thirty-five kilograms per household per month, a flat quantity rather than a per-person one.

Coverage is set as a proportion rather than a number. The Act extends the entitlement to up to 75 per cent of the rural population and up to 50 per cent of the urban population, which works out at roughly 81 crore people and makes it among the largest food entitlement programmes anywhere.

The Act reaches beyond grain. Pregnant women and lactating mothers are entitled to a meal through the local anganwadi and to a maternity benefit of not less than six thousand rupees, and where the entitled quantity is not supplied the State owes a food security allowance in its place.

One provision rewrites who holds the entitlement. The Act directs that the eldest woman who is not less than eighteen years of age in every eligible household shall be head of the household for the purpose of issuing ration cards, which places the claim in a woman's name by default rather than by application.

Eligibility is also wider than the older category it replaced. The Act covers priority households and Antyodaya households identified by the States, not the below poverty line category alone, so restricting subsidised grain to BPL families describes the older system the Act replaced.

Two dates are often confused. The Act received assent on 10 September 2013; 5 July 2013 is the date of the Ordinance that preceded it.

Poshan 2.0 and the Anganwadi Network Behind It

Mission Saksham Anganwadi and Poshan 2.0 is the scheme through which most nutrition services actually reach people. It is delivered through a network of 14 lakh anganwadi centres, and it is issued under the provisions of the Act rather than standing separately from it.

The mission runs on four verticals rather than as a single programme:

• Nutrition support through the Supplementary Nutrition Programme, for children from six months to six years, pregnant women and lactating mothers, and adolescent girls aged 14 to 18 in aspirational districts and the North Eastern Region.
• Early childhood care and education for ages three to six, with early stimulation from birth to three.
• Anganwadi infrastructure, including the upgraded centres from which the Saksham element of the name comes.
• Poshan Abhiyaan, the mission that gives the scheme its monitoring and convergence machinery.

The supplementary nutrition is designed against a gap rather than an absolute. The guidelines state that it is meant to bridge the distance between the recommended dietary allowance and the average daily intake, which is why the norms are expressed as an addition to what a household already provides.

Those norms are set per beneficiary per day: 500 kilocalories and 12 to 15 grams of protein for a child aged six months to six years, 800 and 20 to 25 grams for a severely malnourished child, and 600 with 18 to 20 grams for pregnant women, nursing mothers and adolescent girls. The guidelines add that these norms are under revision.

PM POSHAN and the School Meal as a Statutory Right

A child up to class VIII, or within the age group of six to fourteen, is entitled to one free mid-day meal every day except on school holidays, in schools run by local bodies and in government and government-aided schools. The meal must meet the nutritional standards set out in Schedule II of the Act.

The legal form is what matters here. Because the entitlement sits in a statute rather than in an executive scheme, no administrator may withdraw it, and a failure to supply it triggers the food security allowance that the Act provides for any unmet entitlement.

The delivery vehicle is PM POSHAN, run by the Department of School Education and Literacy, which supplies the meal the statute requires. The right comes from the Act; the scheme only delivers it.

The three instruments fit together. The Act creates the entitlements, Poshan 2.0 delivers services through the anganwadi network, and PM POSHAN delivers the school meal; and the nutrient density discussed in Part 1, on millets only reaches the diets that need it most by travelling through these three.

Sources and Further Reading

• ICMR-National Institute of Nutrition: Dietary Guidelines for Indians, 2024
• World Health Organization: Vitamin A deficiency, Nutrition Landscape Information System
• World Health Organization: Iodine deficiency, Nutrition Landscape Information System
• World Health Organization: Malnutrition, fact sheet
• World Health Organization: Anaemia, fact sheet
• World Health Organization: Healthy diet, fact sheet
• Press Information Bureau: Union Health Ministry releases NFHS-5 findings
• Press Information Bureau: India's Fight Against Anemia, April 2025
• Ministry of Health and Family Welfare: Anaemia Mukt Bharat, operational guidelines
• Press Information Bureau: Global Hunger Index 2021, Government response
• Ministry of Law and Justice: The National Food Security Act, 2013, Gazette of India
• Ministry of Women and Child Development: Mission Saksham Anganwadi and Poshan 2.0, scheme guidelines
• Food Safety and Standards Authority: Fortification of Foods Regulations, consolidated
• Department of School Education and Literacy: Guidelines on the PM POSHAN Scheme
• NCERT: Biology, Class 12, Chapter 10, Biotechnology and its Applications
• Wikipedia: Scurvy
• Wikipedia: Rickets
• Wikipedia: Thiamine deficiency
• Wikipedia: Probiotic
• WHO and UNICEF: Child growth standards and the identification of severe acute malnutrition, joint statement, 2009
• Wikipedia: Marasmus
• Wikipedia: Kwashiorkor
• Wikipedia: Protein-energy malnutrition