SMIP is working towards elimination of micronutriet malnutrirtion through Supplementation and Fortification but in case of Iodine SMIP is only providing information as it is an ongoing process to fortify all the salt in the market with iodine by the GOI (Govt of India )

What is iodine?

Iodine is a chemical element that is required for growth and survival. It is widespread in the environment, but is chiefly derived from the ocean and the soil. Iodine is typically present in relatively low concentrations in the sea and soil; because of its biological importance, iodine tends to be present in living organisms in higher concentrations. It is found in varying amounts in plants and animals, and the quantity we obtain from plants depends on the concentration of iodine in the soils in which they were grown. The most potent source of iodine in the human diet is marine fish and other seafood.

Why do we need iodine ?

Iodine is an essential micronutrient in the human diet. Its most important known function is as a component of thyroid hormones. Thyroid hormones are produced by the thyroid gland (located at the base of the neck). Thyroid hormones play a vital role in the regulation of metabolic processes such as growth and energy expenditure. They are essential throughout childhood for normal brain and physical development. They are also critical for normal development of the baby in the womb, so for women who plan to become pregnant, iodine intake is one of the important nutritional factors they need to take into account

Iodine we need?

A teaspoon of iodine is all a person requires in a lifetime. However, the thyroid gland does not have the capacity to store this amount, so small amounts of iodine must be consumed regularly in the diet. The World Health Organization recommends the following daily intake for optimal iodine nutrition:

If I don't get enough iodine, what happens?

Iodine deficiency occurs in individuals who do not get adequate iodine in their diet. The thyroid gland is presented with the challenge of maintaining production of thyroid hormones for metabolic demands, despite one of the essential components (iodine) being in short supply. Under these circumstances, the thyroid gland enlarges in order to become more effective at its job. This is known as ‘goitre’, and is the most obvious sign of iodine deficiency. However, other changes in physiology can also occur, such as a reduction in thyroid hormone synthesis resulting in lower blood levels of thyroid hormones—a condition known as hypothyroidism. This poses a health hazard for all affected people because it can lead to weight gain, lethargy, intolerance to cold, increased blood cholesterol, mental slowness and reduced heart function.

What are iodine deficiency disorders?

A diet lacking in iodine is associated with a wide spectrum of adverse health effects collectively known as iodine deficiency disorders (IDDs). IDDs can impact on people of all ages, but most severely on the baby while it is developing in the womb or in the period soon after birth.

Goitre is the best known, but least important of the disorders. Iodine deficiency has the greatest impact during pregnancy, due to its devastating effects on the baby’s developing brain and also on physical growth. In the worst cases of severe iodine deficiency, a child may be born with cretinism, a condition characterised by severe mental retardation, growth stunting, apathy, and impaired movement, speech or hearing.

However, even mild iodine deficiency can impair development and cause subtle deficits in visual motor skills, hearing and intelligence. Iodine deficiency is regarded as the world's greatest cause of preventable brain damage, resulting in an estimated 80 million children suffering from some form of permanent mental retardation. In women of child-bearing age, iodine deficiency undermines fertility; and in pregnancy it puts the developing baby at greater risk of miscarriage, abortion or stillbirth. IDDs are a significant threat to the health, wellbeing, and productivity of communities worldwide.

The best dietary sources of iodine-

The richest natural food sources of iodine are seafood and seaweed (such as kelp and nori), because the ocean is a rich reservoir of iodine. Two or three serves a week of seafood will provide sufficient intake of iodine.

Although generally lower than in most seafoods, the iodine levels in foods of animal origin (eggs, meat and dairy products) are higher than in most foods of plant origin, and they may have been further enriched by the use of iodine-supplemented animal feed.

The variation of iodine content in natural foods can be considerable. For example, in Britain iodine levels in fish varied from 110–3,280 micrograms per kilogram. The iodine content of whole milk samples collected in Tasmania in 2002/03 ranged from 110 to 440 micrograms per litre (average level 213 micrograms per litre). Analysis of Australian milk in 1991 showed an average content of 50 micrograms per litre.

Any salt used at home should be an iodised salt (that is, iodine has been added). In Australia, iodised salt contains 25–65 micrograms of iodine per gram of salt. In NZ it varies from 40–80 micrograms per gram. Iodised salt is available at all major supermarkets (either in a green container or with a green label). Note that sea salt is a poor source of iodine—it contains less than two micrograms per gram.

Supplements, and overdosing -a potential problem?

Supplements of iodine may be an important source for individuals who do not eat seafoods, animal flesh, animal products, or iodised salt, or who have a greater requirement for iodine (such as pregnant or breastfeeding women).

Iodine is a listed ingredient in a range of multivitamin supplements available at health food stores, and the dose can vary from 50–150 micrograms per tablet. Kelp tablets are a type of seaweed extract, and can provide an alternative iodine source.

But check with your doctor before starting to take iodine (or any other) supplements. As applies to many supplements and over-the-counter drugs, too much iodine can be toxic. Although most individuals can tolerate a wide range of iodine intake, exposure to extremely high levels (above 1,000 micrograms per day) is potentially harmful. Excessive iodine intake is especially dangerous for those people with a predisposition to “Grave’s Disease”, because high levels of iodine can trigger this condition in susceptible people.

Use only those tablets that state the iodine content on the label, so you know how much you are getting. And, as mentioned above, don’t forget to check first with your doctor that the iodine content of the supplement is appropriate.

who should not take supplements of iodine?

People with certain thyroid disorders—those that result in an overactive thyroid gland (leading to hyperthyroidism)—are often recommended by their doctor to have low iodine diets. Individuals with a family history of thyroid disorders, or who have an existing thyroid problem, may need to take special care and seek medical advice from their doctor.