3. Vitamins are organic substances that are
essential for several enzymatic functions in
human metabolism
A compound is called vitamin when it cannot be
synthesized in sufficient quantities by an
organism, and must be obtained from the diet.
What are Vitamins?
4. Functions of Micronutrients
Acts as hormones (vitamin D)
Acts as antioxidant (vitamin E)
Acts as mediators of cell signaling and
regulators of cell and tissue growth and
differentiation (vitamin A)
Acts as precursors for enzyme cofactor
biomolecules(coenzymes) that help act as
catalysts and substrates in metabolism.
5. VITAMINS
Vitamins are classified according to
solubility into fat soluble & water soluble.
13 vitamins are known, 4 fat soluble
(K,E,D & A) & 9 water soluble (C, Folate &
the B group).
6. VITAMINS
Water soluble - dissolve easily in water
readily excreted from the body.
Fat soluble - absorbed through the
intestinal tract with the help of lipids(fats).
7. VITAMIN A
Vitamin A is a generic term for many related
compounds. Retinol (alcohol), Retinal (aldehyde)
are often called preformed vitamin A. Retinal can
be converted by the body to retinoic acid which is
known to affect gene transcription.
Body can convert b-carotene to retinol, thus
called provitamin A.
8. FUNCTIONS OF VITAMIN A
1. Immunity: important for activation of T lymphocyte,
maturation of WBC & integrity of physiological barrier.
2. Vision: integrity of eye & formation of rodopsin necessary for
dark adaptation.
3. Regulation of gene expression: vital to cell differentiation &
physiologic processes
4. Growth & development
5. Red blood cell production
10. Deficiency Of Vitamin A
•Deficiency of vitamin A leads to:
1. Ocular change
Night blindness & xerophthalmia
2. Extra ocular changes
Growth retardation
Acquired immune deficiency
Anemia
15. Treatment of Vit A Deficiency
• Overall mortality is reduced by 23%
• Death from measles is reduced by 50%
• Death from diarrhea is reduced by 40%
16. TOXICITY
Children and adults ingesting >50,000 IU/day for several
month.
Vitamin A in excess leads to:
•Dermatitis with xanthosis cutis
•Hepatosplenomegaly
•Fatigue, malaise, anorexia, vomiting
•Bone pain & increased risk of fracture
•Pseudotumor Cerebri
•Xray-hyperostosis of the shafts of long bones
17. VITAMIN D
Vitamin D comprises a group of sterols; the most
important of which are cholecalciferol (vitamin D3) &
ergosterol (vitamin D2).
Humans & animals utilize only vitamin D3 & they can
produce it inside their bodies from cholesterol.
Cholesterol is converted to 7-dehydro-cholesterol
(7DC), which is a precursor of vitamin D3.
19. FUNCTIONS
Calcium metabolism: vitamin D enhances
Calcium absorption in the gut & renal tubules.
Cell differentiation: particularly of collagen &
skin epithelium
Immunity: important for Cell Mediated Immunity
& coordination of the immune response.
20. Deficiency of Vitamin D
•Deficiency of vitamin D leads to:
Rickets in small children.
Osteomalacia
21.
22. RICKETS
Sign and symptoms-
• Skeletal deformity
• bowed legs(genu varum) in toddlers
• knock knees (genu valgum) in older children
• craniotabes (soft skull)
• spinal and pelvic deformities
• growth disturbances
• costochondral swelling(rickety rosary)
• harrisons groove
• greenstick fractures
• bone pain and tenderness
• muscle weakness
• dental problems.
23. INVESTIGATIONS
Radiologic changes-loss of normal zone of
provisional calcification adjacent to metaphysis.
Widening of the growth plate.
Splaying and cupping of metaphysis.
Generalized reduction in bone density.
Low circulating levels of 25(OH)D3.
Elevated serum alkaline phosphate.
Calcium level may be normal or low
Phosphate level usually are unchanged or low.
27. VITAMIN C - ASCORBIC ACID
• Humans are among the few species that cannot
synthesize vitamin C and must obtain it from food
• Manufacture of collagen
• Helps support and protect blood vessels, bones,
joints, organs and muscles
• Protective barrier against infection and disease
• Promotes healing of wounds, fractures and bruises
28. SOURCES OF VITAMIN C
• Sources
• Citrus fruits, strawberries, kiwifruit, blackcurrants,
papaya, and vegetables
29. DEFICIENCY OF VITAMIN C
• Deficiency of Vitamin c causes SCURVY
Signs and Symptoms of Scurvy
Small blood vessels fragile
Gums reddened and bleed easily
Teeth loose
Joint pains
Scorbutic rosary: Costochondral junction is more angular
and has a sharper step-off
Dry scaly skin
Lower wound-healing, increased susceptibility to infections,
and defects in bone development in children
Legs assume a “frog like position”(Hips and knees are
semiflexed with the feet rotated outwards)
30. TREATMENT
• Prevented by a diet of Vitamin C
• Daily therapeutic dose of Vitamin C is 100-200mg or more.
• Daily requirement is 45-60mg/day in children
31. THIAMIN – VITAMIN B1
• What it does in the body ?
• Energy production and carbohydrate and fatty acid metabolism
• Vital for normal development, growth, reproduction, healthy
skin and hair, blood production and immune function
• Deficiency due to diets of polished rice
32. BERI BERI- SIGNS & SYMPTOMS
• Develop within 12 weeks
1. Dry Beriberi peripheral neuropathy
• Difficulty walking and paralysis of the legs
• Reduced knee jerk and other tendon reflexes, foot and
wrist drop
• Progressive, severe weakness and wasting of
muscles
2. Wet Beriberi cardiopathy
• Edema of legs, trunk and face
• Congestive heart failure (cause of death)
33.
34. Wrist & foot drop:
Dry Beri Beri
Edema:
Wet Beri Beri
35. RIBOFLAVIN DEFICIENCY
• Deficiency is rare and often occurs with other B
vitamin deficiencies
• Several months for symptoms to occur
Burning, itching of eyes
Angular stomatitis
Cheilosis
Swelling and shallow ulcerations of lips
Glossitis
37. NIACIN – VITAMIN B3
• Essential for healthy skin, tongue, digestive tract tissues, and
RBC formation
• Processing of grains removes most of their niacin content so
flour is enriched with the vitamin
38. DEFICIENCY OF NIACIN (PELLAGRA)
1. ‘Three Ds’: diarrhea, dermatitis and dementia
2. Reddish skin rash on the face, hands and feet which
becomes rough and dark when exposed to sunlight
(pellagrous dermatosis)
• acute: red, swollen with itching, cracking, burning, and
exudate
• chronic: dry, rough, thickened and scaly with brown
pigmentation
3. dementia, tremors, irritability, anxiety, confusion
and depression
40. VITAMIN K
It is a cofactor of the enzyme that catalyzes one step in the
formation of prothrombin.
Needed for the generation of several clotting factors in the
liver.
Source- green leafy vegetables.
Deficiency-coagulation defect due to hypoprothrombinemia
and deficiency of factor VII resulting in hemorrhagic disease
of the newborn.
1mg IM –newborn.
In severe deficiency-2.5 to 5 mg/day parenterally.
41. ANEMIA
• Iron deficiency is the most common cause of
anemia and most common preventable nutritional
deficiency.
42. CAUSES OF IRON DEFICIENCY
Nutritional Blood Loss
1. Mother anemic
2. Increased Fe
demands:(Preterm,IUGR,
Cyanotic heart disease)
3. Prolonged breastfeeding,
cow milk
4. Malabsorption
5. Poor weaning
1. Neonates:
Fetomaternal transfusions
Twin to twin transfusions
Bleeding from umblical cord
Hemorrhagic disease of
Newborn
2. Children:
Hookworm infestation
Rectal polys
IBD
43. SIGNS & SYMPTOMS OF IRON DEFICIENCY
Symptoms
• Tiredness/ Fatigue/ Headache/Breathlessness
Signs
• Pallor: Pale conjunctivae, palms, tongue, lips, skin,
Spoon shaped nails.
• Tachycardia, Systolic murmur
• If Hb<3, check for signs of CHF
44. INVESTIGATIONS:
• CBC: 1) Hemoglobin <11.0 g/dL
• MVC/ MCH/ MCHC are all decreased
• Reticulocyte count: Normal or minimally elevated
• Peripheral blood smear:
Microcytic hypochromic anemia
• Serum Fe levels: Decreased
• TIBC: Increased
• Serum ferritin levels: Decreased
45. ANEMIA- TREATMENT
• Dietary counseling: Infants fortified milk formula less
than 1yr of age
• Dietary diversification
• Foods that are rich in iron include:
• Meat/ Fortified cereals/ Spinach/Lentils and beans
• Iron supplements
• Mild to moderate anemia: 3-6mg/kg/day of iron (3-5
months)
• Severe anemia and cardiac decompensation: Start
blood transfusions, packed RBC’s: (2-3ml/kg)
46. ZINC DEFICIENCY
Zinc essential for the function of many enzymes and
metabolic processes
Zinc deficiency is common in developing countries
with high mortality
Zinc commonly the most deficient nutrient in
complementary food mixtures fed to infants during
weaning
Zinc interventions are among those proposed to help
reduce child deaths globally by 63%.
47. ZINC DEFICIENCY- SIGNS & SYMPTOMS
• Skin lesions
• Immune impairment
• Diarrhea
• Poor growth
• Acrodermatitis enteropathica:
• AR disorder (defect of Zn absorption)
• Begins within 2-4 weeks of weaning
• Perioral/ Perianal dermatitis/
• Failure to thrive
48. Zinc Deficiency- Treatment
Regular zinc supplements can greatly reduce common
infant morbidities in developing countries
• Adjunct treatment of diarrhea
-10 mg/day for infants below 6 months,
-20mg/day of zinc for 10-14 days(>6months)
Zinc deficiency commonly coexists with other
micronutrient deficiencies including iron, making
single supplements inappropriate
Emperical trial of Zinc
supplementation(1ug/kg/day) is safe and
reasonable
