Iodine deficiency disorders (IDDs) refer to a spectrum of health consequences caused by inadequate iodine intake. Iodine is essential for thyroid hormone production which are important for physical and mental development. IDDs range from goiter and hypothyroidism to severe intellectual disabilities. Nepal has a high prevalence of IDDs affecting an estimated 10 million people. Prevention strategies in Nepal include mandatory iodization of salt at the production level and social marketing campaigns to increase awareness and consumption of adequately iodized salt. Monitoring of iodine levels in salt and urine are also conducted to evaluate IDD control programs.

1. IODINE DEFICIENCY
DISORDERS
DR. PRERNA BANSAL
MBBS, MD COMMUNITY MEDICINE, FELLOWSHIP IN DIABETES
LECTURER, COLLEGE OF MEDICAL SCIENCES
BHARATPUR, CHITWAN, NEPAL

2. INTRODUCTION
Iodine is essential for human health as it is a
constituent of thyroid hormones, which play an
important role in physical and mental
development.
Iodine is one of the leading causes of preventable
mental retardation and brain damage in the world.
Iodine deficiency not only leads to goiter and
cretinism but also to a much broad spectrum of
disorders.

3. IODINE

4. IODINE
• It is an essential micronutrient.
• Required in minute amounts for normal growth and
development and well being of all human beings.
• Synthesis of thyroid hormones (20-50 mg iodine)
Thyroxine (T₄)
Tri-iodothyronine(T₃)
• TSH can control uptake of iodine by thyroid gland,
indirectly control of BMR

5. • Iodide uptake is a critical first step in thyroid hormone
synthesis.
• 10 to 25% of radioactive tracer (e.g., 123I) is taken up by
the normal thyroid gland over 24 h;
• Iodine deficiency, there is an increased prevalence of
Goiter.
• When deficiency is severe, hypothyroidism and cretinism
develops.
• Iodine deficiency remains the most common cause of
preventable mental deficiency

6. Absorption, Circulation and Function of iodine:
• Iodine in diet absorbed as iodide which
Circulates in blood when enters in
thyroid gland becomes radioactive
iodine then combines with tyrosine to
form mono > di > tri-
iodotyrosine (T3)
and tetra-iodotyrosine (T4)

7. Hormone regulation

8. • Adult human body contains about 50 mg of iodine.
• Blood level is about 8-12 µg/dl
• Daily requirement is about 150 µg/ day for adults
• Deficiency
1. Goiter (Adult)
2. Cretinism (Children), hypothyroidism &
hyperthyroidism

9. Iodine requirement
To meet iodine requirements, the current
recommended daily iodine intakes are:
50µg for infants (first 12 months of age)
90µg for children (2-6 years of age)
120µg for school children (7-12 years of age)
150µg for adults (beyond 12 years of age)
200µg for pregnant and lactating women

10. SOURCES
• Sea foods like sea fish, sea salt
• Cod liver oil
• Milk, meat, vegetables, cereals
• Drinking water (10%), Food (90%)
• Fresh water 1-50 µg/ L
• Iodized salts 1gm - 76 µg

12. GOITROGENS
• Chemical substances leading to the
development of goitre
• Interfere with iodine utilization by the thyroid
gland
• Cyanoglycosides and thiocynates – imp.
dietary goitrogens
• May occur in food and water
• Cabbage, cauliflower etc.

13. IODINE DEFFICIENCY
DISORDERS

14. Iodine Deficiency Disorders refer to
a spectrum of health consequences
resulting from inadequate intake of
iodine.
The adverse consequences of iodine
deficiency lead to a wide spectrum
of problems ranging from abortion
and still birth to mental and physical
retardation and deafness, which
collectively known as Iodine
Deficiency Disorders (IDDs).
14

15. IDDs – Population effects of severe iodine
deficiency disorders termed IDDs.
IDDs include –
• Endemic goiter
• Hypothyroidism
• Cretinism
• Decreased fertility rate
• Increased infant mortality rate
• Mental retardation

17. The spectrum of Iodine-deficiency disorders in
approximate order of increasing severity
Disorders Level of severity
Goitre Grade-1
Grade-2
Grade-3
Grade-4
Hypothyroidism Varying combination of clinical
signs (depending on age of
onset, duration and severity)

18. Subnormal intelligence
Delayed motor milestones
Mental deficiency Variable severity
Hearing defects
Speech defects
Strabismus Unilateral
Bilateral

19. Nystagmus
Spasticity (Extrapyramidal)
Neuromuscular Weakness Muscle weakness in legs, trunk
Spastic diplegia
Spastic quadriplegia
Endemic cretinism Hypothyroid cretinism,
Neurological cretinism
Intrauterine death
(Spontaneous abortion,
miscarriage)

20. Symptoms and Signs of IDDs
• Endemic goiter
Pathophysiology – Lack of iodine decrease T3,
T4 TSH Stimulates Follicular cells of thyroid
gland cause hyperplasia of those cells resulting
enlargement of thyroid gland called goiter.

21. Clinical features of Endemic goiter
Children present with diffuse goiters, while
adults present with nodular goiters.
If a goiter is large enough, patients may
complain of compressive symptoms such
as hoarseness, shortness of breath,
cough, or dysphagia.

22. Presentation of Endemic goiter

23. Differential diagnosis of goiter
• Autoimmune Hypothyroidism
• Hyperthyroidism (Toxic nodular)
• De Quervain thyroiditis
• Thyroid carcinoma
• Thyroxine binding globulin deficiency

24. Clinical features of Hypothyroidism
• Fatigue
• weight gain
• cold intolerance
• dry skin
• constipation
• depression

25. Clinical features of Cretinism – It is most
extreme form of IDDs: Two types
– Neurologic and myxedematous
• Neurologic: mental retardation, abnormal
gait, and deaf-mutism but not by goiter or
hypothyroidism in the child.
• Myxedematous: mental retardation, short
stature, goiter, and hypothyroidism

26. A man and 3 females (age range, 17-20 y)with
myxedematous cretinism from the Republic of the Congo
in Africa, a region with severe iodine deficiency

27. Investigation of Iodine deficiency
• 24 hours urinary iodine – 50
– 100 mcg/L – Mild deficiency 20 –
49 mcg/L - Moderate deficiency < 20
mcg/L - Severe deficiency
• TSH
• T4
• 24 hour radio iodine uptake
• Thyroid ultrasound will show increase size

28. Treatment of IDDs
• Iodine supplementation – 150 mcg/day
• In non toxic goiter – Thyroxine
• In large goiter – Surgical intervention
• Prevention – Diet ; Seafood, iodized salt
(iodized salt – 100 mcg/gm as potassium iodide that is
2 gm iodized salt contain daily adult requirement of
iodine)

29. Importance of the problem

30. Prevalence
• 1 billion persons exposed
• 200 million persons affected (goitres)
• 26 million cases of mental problems
• 6 million cases of cretinism

31. Summary of World’s iodine Nutrition
0
1750
3500
5250
7000
1
6089
2839 3034
Total World's popul
Sufficient
Deficient
Population in Millions

32. World’s Iodine Nutrition by population
distribution
47%
50%
3%
Sufficient
Deficient
Excess

33. World’s Iodine Nutrition by Number of countries
84
72
3
Deficient
Sufficient
Excess

34. Iodine Nutrition in the World

35. Iodine deficiency world wide
WHO Regions a
Proportion of
population
with UI < 100 ต
g/L (%)
Population
with UI < 100 ตg/L
(in millions) b
Africa 47.6 48.342
The Americas 14.1 9.995
Eastern
Mediterranen
55.4 40.224
Europe 59.9 42.206
South East Asia 39.9 95.628
Western Pacific 19.7 36.082
Total 36.9 272.438

36. Iodine Deficiency prevalence in Nepal
Iodine deficiency disorders (IDD) affect an estimated
10 million Nepalese nationwide
A Goiter prevalence of 41.5% among females and
38.4% among males and school-aged children 6-14
years

37. Estimated Goiter Prevalence:
Note: The prevalence in the sample was assessed
for grades, 1, 2, as well as TGR (total goiter rate)
Group
Sample
Size
Indicator
Prevalence in
Sample Population
Affected*
G1 G2 TGR
Women 15,540 Visible or
palpable
goiter
(grades 1
and 2)
48.1 1.3 50.0 2,887,515
Children
6-11
yrs (scho
ol aged
children)
15,542 Visible or
palpable
goiter
(grades 1
and 2)
40.5 0.0 40.5 1,328,648
The Nepal
Micronutrient
Status Survey
was completed
in 1998.

38. MAGNITUDE OF PROBLEM
• Iodine deficiency disorder is most endemic problem in
Nepal.
• It is endemic mostly on western mountains and mid hills
during 1970s.
• It was during 1973 Government of Nepal and Ministry of
Health and Population adopted a policy to fortify all
edible common salt with iodine.
• In 1998 MOH and population issued ‘two child logo” for
quality certification of iodized salt with 50ppm iodine at
production level.
• From fiscal year 2060/61 Child Health division decided to
celebrate February as ‘the month to create awareness
about iodized salt’ through mass campaigns.

39. • IDD is problem of considerable magnitude in India,
Nepal, Bhutan, Myanmar, Indonesia, Sri lanka,
Thailand.
• South-East Asia is the most affected region in the
world.
• Himalayan goitre belt is the world’s biggest goitre
belt extending about 2400km., from Kashmir to
Naga Hills in the east and also affects northern
states from J & K to Manipur.

40. There is legislation governing IDD in Nepal. It was passed in
1955 and has been revised since. Salt iodization is
mandatory at the level of 20-60 ppm.
Prevention of Iodine Deficiency
The estimated percent of households consuming salt
with some iodine is 91%. The estimate of households
consuming adequately iodized salt (15ppm or above)
is 63%.
Sourced from the Between Census Household Information, Monitoring and Evaluation System 2000-
BCHIMES.

41. GOITRE CONTROL
The components of Goitre control program are
• Iodized salt and oils
• Monitoring and surveillance
• Man power Training
• Mass Communication

42. IODIZED SALT AND OIL
• Iodized salt is the most widely used prophylatic measure
against endemic goitre.
• Iodine should be 30 ppm at the production level, 15 ppm
at the consumer level.
IODIZED OIL
• Intramuscular injection of iodized oil (mostly poppy-seed
oil).
• 1ml of intramuscular injection will provide protection for
about 4years.
• It is useful for places where iodized salt is not feasible.
IODIZED OIL,ORAL
Are effective but are expensive.

43. IODINE MONITORING
• There are laboratory set within the countries
for iodine monitoring, these are essential for
Iodine excretion determination
Determination of iodine in water, soil and food
Determination of iodine in salt for quality
control

44. MAN POWER TRAINING
• Manpower training required for goitre control
regarding legal enforcement and public
education
MASS EDUCATION
• A power tool to create public awareness and
should be fully utilized

45. GOALS AND OBJECTIVES
• The WHOs regional strategy for the control of IDD
aimed at “reduction of the prevalence of goitre in
the areas of endemicity to 10% or below by the
year 2000.”

46. NEPAL
• SPECIFIC MDGs-
• Increase consumption of adequately iodized salt (≥
15 ppm) at House holds level to 88% by the year
2015
• OBJECTIVE & NUTRITION PROGRAM COMPONENT
To virtually eliminate IDDs and sustain the
elimination by 2017

47. MAIN INTERVENTIONS
• Nutritional supplementation
• Enrichment
• Nutrition education
• Rehabilitation

48. INDICATORS
• IODIZED SALT COVERAGE
No. of Households using adequately
iodized salt (≥15 ppm) x 100
No. of Households surveyed
• URINARY IODINE EXCRETION (UIE)
≥ 100 µg iodine / L of urine (Median)

49. Objective
• To virtually eliminate iodine deficiency
disorders and vitamin A deficiency and
sustain the elimination.

50. STATEGIES FOR CONTROL OF IDD
• Strengthen the implementation of Iodized Salt Act,
2055 for regulation and monitoring of iodized salt
trade to ensure that all edible salt is iodized.
• Increase the accessibility and market share of iodized
packet salt with ‘two child’ logo.
• Create awareness about the importance of use of
iodized salt for the control of IDD, through Social
Marketing Campaign

51. • Universal salt iodization
• Social marketing of government certified
two‐child‐logo adequately iodized salt.
• Ensure systematic monitoring of iodized salt
distribution

52. ACTIVITIES
• Regular supervision & monitoring of iodized
salt conducted at STC’s warehouse
• Continued Iodized Salt Social Marketing
Campaign (V) continued in Dhanusa,
Mahottari, Sarlahi and Siraha districts
• IDD month celebrated throughout the country
in the month of February for intensification of
promotional activities

53. Contd….
• Surveillance on consumption of iodized salt along
with Vit A was continued as earlier & FCHV registers
used for Intensification of Maternal & Neo-natal
Micronutrient Program (IMNMP) was also used for
this purpose
• National Scale Survey for tracking the process
towards prevention of IDD in Nepal is continued
• Distributed subsidized salt in Remote & inaccessible
districts

54. Contd…..
• Well equipped modern warehouses have been
constructed in various parts of the country for
safeguarding buffer stock
• Iodized Salt Social Marketing Expansions in 4
districts – Jhapa, Saptari, Sunsari & Morang in
FY 2008/2009 under SHNP

55. THANK YOU
THANK YOU