Iodine deficiency (IDD) is the single most common cause of preventable mental retardation and brain damage in the world. Iodine (Greek, ioeides = violet) is required for the synthesis of thyroid hormone, a key regulator of neurological development. (More? Endocrine Development - Thyroid)
IDD causes goiters and decreases the production of hormones vital to growth and development. Children with IDD can grow up stunted, apathetic, mentally retarded and incapable of normal movement, speech or hearing. IDD in pregnant women cause miscarriage, stillbirth and mentally retarded children. A teaspoon of iodine is all a person requires in a lifetime, but because iodine cannot be stored for long periods by the body, tiny amounts are needed regularly. In areas of endemic iodine deficiency, where soil and therefore crops and grazing animals do not provide sufficient dietary iodine to the populace, food fortification and supplementation have proven highly successful and sustainable interventions. Iodized salt programs and iodized oil supplements are the most common tools in the fight against IDD.
Iodine incorporated into thyroid horomone, Thyroxine (T4)
(Information from International Council for the Control of Iodine Deficiency Disorders)
The World Health Organization has made progress recently since the primary intervention strategy for IDD control, Universal Salt Iodization (USI), was adopted in 1993.
Iodization can be carried out using potassium iodide or potassium iodate; or sodium iodide or sodium iodate.
Salt was chosen because it is widely available and consumed in regular amounts throughout the year, and because the costs of iodizing it are extremely low - only about US$0.05 per person per year. Where salt iodization has been in place for over five years, improvement in iodine status has been overwhelming.Over the last decade, the number of countries with salt iodization programmes doubled, rising from 46 to 93. As a result, today 68% of the 5 billion people living in countries with IDD have access to iodized salt and the global rates of goitre, mental retardation and cretinism are falling fast.
(some text information from WHO page)
The current WHO recommended daily iodine intakes are:
(More? WHO Nutrition Guidelines | Endocrinology - Iodine intake)
This information is about Iodine the element, dietry intake is in the form of iodine as a salt. The solid halogen was discovered in 1811 by Bernard Courtois (1777-1838) in seaweed. Iodine (Greek, ioeides = violet) was named for the color of its vapour.
Australia New Zealand Food Standards Code STANDARD 2.10.2 SALT AND SALT PRODUCTS
(from IDD Prevalence and Control Program Data)
(For other countries see also IDD Regional Data Page)
IDD Prevalence and Control Program Data
Last Modified: 6/98
Australia
I. IDD Prevalence
Goitre:
No national IDD data. Goiter historically limited to mountains of east and Tasmania. Before prophylaxis was introduced in 1950, IDD was greater than 50%. Presently, IDD not likely.
Cretinism:
Not present
TSH:
Neonatal TSH in screening shows levels compatible with iodine sufficiency, including Tasmania.
Urinary Iodine:
Current values: Tasmania 229-356 mcg/L, Sydney 180 mcg/L.
II. Salt Legislation
III. IDD Coordination
IDD Responsible Parties:
No national surveillance program
IV. Salt Supply
Iodized table salt has been available for over 50 years. However, noniodized salt is preferred and data indicate that less than a third of the consumed salt is iodized.
V. Supplementation:
Iodized bread was introduced in 1963 in Canberra and in 1966 in Tasmania. It continues to be a source of iodine.
VI. Monitoring Activities
The following indicators are available to monitor IDD:
VII. Comments
Dietary diversification and use of iodine in farm animals has contributed to iodine sufficiency, and iodine deficiency does not appear a current problem. However, no national surveillance system exists. Recent informal reports raise questions of return of iodine deficiency to Tasmania and assessment is underway (1998).
VIII. Sources
IDD NL 9(1):11, 1993
Australia New Zealand Food Standards Code STANDARD 2.10.2 SALT AND SALT PRODUCTS
The Australian NHMRC (1988) recommends neonates be assessed for follow-up care under the following conditions.
(see the NHMRC WWW Page)
For Normal Childhood Development see Publications (or NHMRC WWW Page)
You should look at normal development. Development Notes
Alternatively, go on to look at Systematic Development of organs and tissues.
For those wanting to see dynamic processes of development (and have a reasonably quick connection) then the Movies pages are good for watching changes occur.
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How and why do things go wrong in development?
Abnormalities in human development can be due to many different factors, this page gives a few starting points to look at the topic of iodine deficiency and its association with various birth defects.
Please email Dr Mark Hill if you wish to make a comment about this current project.