zinc in health and disease

1. Dr.Lokesh R
pediatrics

2. INTRODUCTION
• Zinc, a divalent cation, Atomic no-30
• Essential micro-nutrient
•Role of zinc- Over 300 metalloenzymes and
over 2000 transcription for regulation of lipid,
protein and nucleic acid metabolism, and gene
transcription.

3. DIETARY SOURCES(mg/100grams)
• Oysters - 25
• Meat - 5.2
• Nuts - 3
• Shell fish -2.7
• Poultry -1.5
• Eggs - 1.3
• Milk products - 1.2
• Cereals - 1
• Bread - 1
• Fish -0.8
• Green vegetables -0.4
• Potatoes - 0.3
• Fresh fruits -0.09

4. METABOLISM OF ZINC

5. RDA
• Infants
• 0 - 6 months: 2* (mg/day)
• 7 - 12 months: 3* mg/day
• *Adequate Intake (AI)
• Children
• 1 - 3 years: 3 mg/day
• 4 - 8 years: 5 mg/day
• 9 - 13 years: 8 mg/day
• Adolescents and Adults
• Males age 14 and over: 11
mg/day
• Females age 14 to 18 years: 9
mg/day
• Pregnant and lactating
mothers: 25mg/day
Uptodate.com

6. PHYSIOLOGICAL FUNCTIONS OF ZINC
• Biochemical functions :
– Cofactor for enzymes
– Activity of zinc finger proteins
• Cellular functions :
– Growth & cell development
– Cell membrane integrity
– Tissue growth & repair
– Wound healing
Immunological functions : function of
neutrophils, T cells, B cells and NK cells

7. PHYSIOLOGICAL FUNCTIONS OF ZINC
• Endocrinological functions:
o Reproduction: spermatogenesis
o Thyroid function
o Pancreatic function-Insulin storage and release
o Prolactin secretion
o Thymopoetin synthesis
• Neurological function: Cognition, memory, taste
acuity, vision
• Hematological function : coagulation factors
• Skeletal function : Bone mineralization

8. ZINC AND IMMUNITY
• impaired phagocytic function, lymphocyte
depletion, decreased immunoglobulin
production, a reduction in
the T4+/T8+ ratio, and decreased
interleukin (IL)-2 production

9. ZINC DEFICIENCY
• The true prevalence of mild zinc deficiency is not
known because of the non-specificity of
symptoms and imprecise diagnostic methods
• Indirect diagnosis by supplementation of zinc 1-
2 weeks and improvement in symptoms
• More common in developing countries

10. ZINC DEFICIENCY CAUSES
 Dietary zinc depletion -low zn diet,
binding of zn Phytates, fiber, iron and copper
 Malabsorption
 Burns
 Chronic renal disease
 Acrodermatitis enteropathica
 Crohn disease
 Cystic fibrosis
 TPN
 Liver disease and alcoholism

11. ZINC DEFICIENCY CLINICL FEATURES
• Mild – Depressed immunity, impaired taste and smell,
onset of night blindness, decreased spermatogenesis.
• Moderate -growth retardation and delayed puberty in
adolescents, hypogonadism in males, rough skin, poor
appetite, mental lethargy, delayed wound healing, night
blindness
• Severe –severe immune suppression, frequent
infections, bullous pustular dermatitis, diarrhoea,
alopecia

12. ACRODERMATITIS ENTEROPATHICA
• AR inherited partial defect in intestinal zinc absorption.
• encodes a protein that appears to be involved in zinc
transportation
• erythematous and vesiculobullous dermatitis
• alopecia, ophthalmic disorders, diarrhea, severe growth
retardation, delayed sexual maturation, neuropsychiatric
manifestations, and frequent infections.
• Replacement doses of 3 mg/kg/day of elemental zinc

13. ACRODERMATITIS ENTEROPATHICA

14. DIAGNOSIS
• Blood investigations- zinc in plasma,(spectrophotometric)
erythrocytes, neutrophils, lymphocytes, and hair
• < 60 mcg/dL
• Hypoalbuminemia - decreased levels
• Zinc levels in neutrophils or lymphocytes may be more
sensitive
• Zinc levels in lymphocytes (<50 mcg/1010 cells) or
granulocytes (<42 mcg/1010 cells)
• Depressed serum alkaline phosphatase levels

15. Treatment
Dose (elemental zinc)
• Infants and children-0.5 to 1 mg/kg/day 1-3 divided
doses
• 1-2mg/kg impaired absorption, diarrhoea,burns
• 3 mg/kg/day acrodermatitis enteropathica / wilson’ s
disease.
• Diarrhea treatment malnourished (WHO/UNICEF 2004)
• < 6 months 10mg/day for 10-14 days
• > 6months 20mg/day for 10-14 days

16. Zinc in acute diarrhea
• Reduces duration of diahheal episode by 25%
• Decrease by about 25% the proportion of episodes
lasting more than seven days
• It is associated with a 30% reduction in stool volume
• Conclusion: significant beneficial impact on the clinical
course of acute diarrhea: reduces both severity and
duration, also decrease in diarrheal episodes 2-3 months
WHO/UNICEF Joint statement: Clinical management of acute diarrhea.
WHO/FCH/CAH/04.7. Geneva, 2004.

17. aZinc in persistent diarrhoea
• Zinc-supplemented children had: – 24% lower
probability of continuing diarrhoea – 42% lower
rate of treatment failure or death
• Conclusion: zinc supplementation reduces the
duration and severity of persistent diarrhoea
UNICEF/TACRO, Health and Nutrition/Immunization Plus

18. Zinc in bloody diarrhoea
• Positive impact of the prevalence of dysentery in the
month following the supplementation
• Improves seroconversion to shigellaciddal antibody
response and increases the proportions of circulating B
lymphocytes and plasma cells and the IgA-specific
immunoglobulin response
Conclusion: zinc supplementation should be given as an
adjunct to antibiotic treatment of bloody diarrhoea
UNICEF/TACRO, Health and Nutrition/Immunization Plus

19. Adverse Reactions
• Central nervous system: Dizziness, headache
• Gastrointestinal: Abdominal cramps, diarrhea,
nausea, vomiting

20. ZINC TOXICITY
• Doses up to 10 times tolerated
Acute poisoning 1 to 2 g zinc sulphate
CF -nausea and vomiting associated with irritation and
corrosion GI tract, acute renal failure ,tubular necrosis
or interstitial nephritis
Symptomatic treatment
chronic intake > 100 mg per day may be associated with
copper deficiency
Treatment; EDTA

21. Cochrane acute respiratory group
zinc and common cold
• 18 JUN 2013
• Zinc <24 hrs, onset of symptoms reduces the duration of common cold
symptoms in healthy people
• zinc lozenges formulation widely studied, significant reduction in the
duration of cold at a dose of ≥ 75 mg/day
• currently no firm recommendation can be made because of insufficient
data.
• When using zinc lozenges (not as syrup or tablets) the likely benefit has to
be balanced against side effects, notably a bad taste and nausea.

22. Zinc supplements for treating thalassaemia
and sickle cell disease
20 June 2013.
Aim-effect of zinc supplementation in the treatment of thalassaemia
and sickle cell disease
In Thalassaema
Height velocity – increased. No change in Hb,
Conclusion- no evidence from RCT- any benefit of zinc,
Sickle anemia
• total number of clinical infections ,who received zinc
1 year
• number of sickle cell crises who received 3 months and 1 year
• Hb% level and anthropometry measurements were not significantly
different,
• Conclusion- mixed evidence , more trials needed

23. Zinc supplementation for the prevention of pneumonia in
children aged 2 months to 59 months, 26 January 2010.
• To evaluate the effectiveness of zinc supplementation in the prevention
of pneumonia in children aged 2 m to 59 m
• 6 trials and 7850 participants in the meta-analysis
• The studies were conducted in Bangladesh, India, Peru, and South
Africa
• Conclusion- significantly associated with reducing the incidence and
prevalence of pneumonia among children of 2 to 59 months of age.
Evidence provided so far from randomized controlled trials is sufficient
to recommend zinc intake in deficient populations through
supplementation, dietary improvements, or fortification, for enhancing
child survival.

24. Oral zinc for treating diarrhoea in children
31 Jan 2013•
To evaluate oral zinc supplementation for treating children with acute or
persistent diarrhoea.
• 24 trials, 9128 children
• shorten the duration of diarrhoea by around 10 hours
• In children with signs of moderate malnutrition the effect appears greater, reducing
the duration of diarrhoea by around 27 hours
• < 6 months infants no effect on mean diarrhoea duration
• No trials reported serious adverse events, but vomiting in both age group
Persistent diarrhoea
• Shortens by 16 hours
conclusions
• In areas with zinc deficiency or the prevalence of moderate malnutrition is high, zinc
may be of benefit in children >6m
• current evidence does not support the use of zinc supplementation in children <6m
infants

25. Commonly used brands

26. REFERENCES
• Nutrition and child development KE Elizabeth 4th edition
• www.uptodate.com
• Clinical biochemistry, Allan gaw 5th edition
• http://www.zinc.rg/info/zinc_essential_for_human_health
• WHO/UNICEF Joint statement: Clinical management of acute
diarrhea. WHO/FCH/CAH/04.7. Geneva, 2004.

28. Thank you