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VITAMINS.pptx

  1. By Dr. LASYA
  2. Contents: • Introduction • History and Nomenclature • Classification of Vitamins • Differences between water and fat soluble Vitamins • Fat soluble Vitamins • Water soluble Vitamins • Vitamins deficiency and Oral manifestations • Public health significance • Conclusion • References
  3. INTRODUCTION • Vitamins may be regarded as organic compounds required in the diet in small amounts to perform specific biologic functions for normal maintenance of optimum growth and health of the organisms • Generally, vitamins are not synthesized by the body, and need to be supplied through the diet
  4. History and Nomenclature • HOPKINS - Coined term ACCESSORY FACTORS to unknown and essential nutrients present in the natural foods • FUNK - 1) Isolated an active principle from rice polishing's and in yeast cured Beri - Beri in pigeons 2) Coined the term VITAMINE from the words vital + amines 3) Later it was called “ VITAMIN ” • Mc COLLUM and DAVIS - Introduced the usage of A, B, and C to vitamins
  5. CLASSIFICATION • There are about 13 vitamins, essential for humans classified as follows
  6. Energy - Releasing Hematopoietic Vitamins Water Soluble Fat Soluble Others Non-B-Complex B-Complex Ascorbic acid (vitamin C) Vitamin A Vitamin D Vitamin E Vitamin K Thiamine (B1) Riboflavin (B2) Niacin (B3) Biotin Pantothenic Acid Folic Acid Vitamin (B12) Pyridoxine (B6) Pyridoxal Pyridoxamine
  7. 1) Major vitamins 2) Solubility in fat 3) Water solubility 4) Absorption 5) Storage 1) A,D,E,K 2) Soluble 3) Not soluble 4) Along with lipids, requires bile salts 5) Stored in liver and adipose tissues 1) B and C 2) Not soluble 3) Soluble 4) Simple absorption 5) No storage Fat soluble Water Soluble
  8. 6) Excretion 7) Toxicity 8) Deficiency 9) Treatment of deficiency 6) Not excreted 7) Hypervitaminosis may result 8) Manifests only when stores are depleted 9) Single large doses may prevent deficiency 6) Excreted 7) Non toxic, since excess is excreted 8) Manifests rapidly as there is no storage 9) Regular dietary supply is required Fat Soluble Water Soluble
  9. Vitamers: • Chemically similar substances that possess qualitatively similar vitamin activity Eg: Retinol A Retinal Retinoic Acid Pyridoxine Pyridoxal Pyridoxamine B6
  10. FAT SOLUBLE VITAMINS
  11. VITAMIN A • Fat soluble vitamin • Present only in foods of animal origin • Carotenes - Plants
  12. Dietary Sources: Animal sources • Liver • Kidney • Egg yolk • Milk • Cheese • Fish liver oils Plant sources • Carrots • Papaya, Mangoes • Avocado, Melon • Pumpkins
  13. RDA (Recommended Dietary Allowance): Men - 1000 RE (3500 IU) Women - 800 RE (2500 IU) Children - below 6 years - 350 - 400 µg Retinol - 6-17 years – 600 µg Retinol Pregnancy – 800 µg Retinol Lactation – 950 µg Retinol 1 RE – 1 µg of Retinol 1 IU – 0.3 mg of Retinol
  14. Biochemical Functions: • Vision - the role of vit A in the process of vision was first elucidated by GEORGE WALD(1968) • The events occur in a cyclic process known as Rhodopsin Cycle (or) Wald’s Cycle
  15. RODS and CONES: • Retina of eye possesses rods and cones • Human eye - 10 million rods 5 million cones • Rods –Periphery – Dim light vision • Cones – Centre – Bright light and color vision
  16. Other Biochemical Functions: Involved in cell growth and differentiation by regulating protein synthesis Maintenance of proper Immune system Synthesis of Glycoproteins Synthesis of Transferrin – Iron transport protein Helps in Cholesterol synthesis Beta carotenes has Antioxidant property Prevent Keratin synthesis by maintaining healthy epithelial tissue
  17. Deficiency of Vitamin A: 1) Night Blindness 2) Conjuctival Xerosis 3) Bitot Spots 4) keratomalacia Night Blindness: Difficulty to see in dim light • Due to impairment in dark adaptation • Prolonged deficiency irreversibly damages number of visual cells
  18. Conjuctival Xerosis: • First clinical sign of vitamin A deficiency • Conjunctiva becomes dry and non – wettable • Appears muddy and wrinkled instead of smoothy and shiny
  19. Bitot spot’s: • Triangular, pearly white or yellowish foamy spots on bulbar conjunctiva on either side of the cornea • Frequently bilateral
  20. Keratomalacia: • The cornea may becomes soft and may burst • It’s a rapid process • If the eye collapses, vision is lost • Treatment: • Administration of massive (2,00,000 IU or 110 mg of retinol palmitate ) orally on 2 successive days
  21. Other Deficiency Manifestations: • Growth retardation due to impairment in skeletal formation • Sterility in males • Skin becomes dry and rough • Keratinization of epithelial cells of GIT, Urinary tract, Respiratory tract increased Bacterial infections
  22. Hypervitaminosis A : • Total serum vit A level is elevated (Normal -20 -50 µg/dl) • Symptoms: Dermatitis Enlargement of liver Skeletal decalcification Tenderness of long bones Weight loss Hair loss Irritability Joint pains
  23. Treatment: • Stopping high intake of vitamin A – in case of hypervitaminosis • Administration of massive dose (2,00,000 IU or retinol palmitate) orally on 2 successive days
  24. VITAMIN D • ANGUS – Isolated and named it as CALCIFEROL • Resembles sterols in structure • Functions like hormone
  25. Synthesis:
  26. Dietary Sources: • Fatty acids • Fish liver oils • Egg yolk • Cheese • Butter
  27. RDA: • 400 IU or 10 mg of cholecalciferol • Countries with good sunlight – 200 IU or 5 mg
  28. Biochemical Functions: Increases the intestinal absorption of calcium and phosphate by increasing of a specific Calcium binding protein Essential for bone formation Along with Parathyroid hormone increases mobilization of calcium and phosphate from the bone Minimizes the excretion of calcium and phosphate through the kidney, by decreasing their excretion and enhancing Reabsorption
  29. Deficiency: 1) RICKETS - In young children aged 6 months to 2 years • Due to reduced calcification of young bones • Characterized by Growth failure Bone deformity Muscular hypotonia Tetany and convulsions • Elevated conc. Of alkaline phosphatase in serum
  30. • Bony deformities - Bow legs Deformed pelvis Pigeon chest Harrison’s sulcus Rickety rosary kyphoscoliosis • Walking and Teething are delayed
  31. 2) OSTEOMALACIA: • In adults • Women • During pregnancy and lactation • Demineralization of bones increased susceptibility to fractures
  32. Prevention: • Educating parents to expose their children regularly to sunshine • Periodic dosing of young children with Vitamin D • Vitamin D rich diet
  33. Hypervitaminosis D: • Vitamin D is most toxic in overdoses (10-100 times RDA) • Toxic effects – demineralization of bones • Increased calcium absorption from the intestine Increased calcium in plasma Deposition of calcium in kidneys and arteries • Formation of stones in kidneys • Also associated with nausea, loss of appetite, increased thirst and weight loss
  34. VITAMIN E • Tocopherol • Naturally occurring Antioxidant
  35. • ANTI STERILITY HORMONE - as it is essential for normal reproduction in many animals • Vitamin in search of a disease - due to lack of any specific vitamin E deficiency disease in humans • EVANS and his associates - Isolated compounds of vitamin E activity and named as “TOCOPHEROL”
  36. Dietary sources: • Wheat germ oil • Cotton germ oil • Peanut oil • Corn oil • Sunflower oil • Meat • Milk • Butter • Eggs
  37. RDA: • Women - 8 mg (12 IU) of alpha Tocopherol • Men – 10 mg (15 IU) of alpha Tocopherol 1 mg of alpha Tocopherol - 1.5 IU
  38. Biochemical functions: Prevents peroxidation of PUFA (Poly unsaturated fatty acids) in various tissues and membranes. Protects RBC from hemolysis by oxidizing agents Essential for the membrane structure and integrity of the cell – regarded as Membrane Antioxidant along with ‘Se’ Increases synthesis of Heme by enhancing the activity of enzymes delta – ALA (aminolevulenic acid) synthase and dehydratase Associated with reproductive functions and prevents sterility
  39. Required for cellular respiration through electron transport chain Essential for optimal absorption of amino acids from the intestine Involved in proper synthesis of Nucleic acids Protects liver from toxic compounds like carbon tetrachloride Works in association with vit A, C, and beta carotenes to delay the onset of cataract
  40. Deficiency symptoms: • In Animals – Sterility Degenerative changes in muscle Megaloblastic anaemia Changes in CNS • In Humans – Increased fragility of erythrocytes Minor neurological symptoms
  41. VITAMIN K • Only fat soluble vitamin with a specific coenzyme functions • Required for production of blood clotting factors
  42. Dietary sources: • Cauliflower • Cabbage • Alfa Alfa • Tomatoes • Spinach • Egg yolk • Cheese • Liver • meat
  43. RDA: • Adult – 70 – 140 µg/day
  44. Biochemical Functions: Brings about the post translational modification of Blood Clotting factors The clotting factors 2, 7, 9, 10 are synthesized as inactive precursors in the liver Acts as a coenzyme for the carboxylation of Glutamic acid present in the proteins
  45. Deficiency Symptoms: Leads to lack of active prothrombin in circulation Increased blood clotting time Treatment – Injection of vitamin K (IM)
  46. Hypervitaminosis K: • Increased levels of vitamin K results in Haemolytic Anaemia Jaundice In Infants
  47. Antagonists of vitamin K: • Heparin • Bishydroxy coumarin • Salicylates • Dicumarol - Structurally related to vitamin K and acts as competitive inhibitor in the synthesis of active Prothrombin Acts as Anticoagulants
  48. WATER SOLUBLE VITAMINS
  49. VITAMIN C • Water soluble versatile vitamin • Plays important role in human health and disease
  50. Dietary Sources • Citrus fruits • Gooseberry (Amla) • Guava • Cabbage • Spinach • Tomatoes • Adrenal glands • gonads High source of vitamin C
  51. RDA: • Adults - 60 -70 mg • 20 – 40% increase – Recommended for women during pregnancy and lactation
  52. Biochemical Functions: Required for bone formation Plays an important role in collagen formation. Acts as coenzyme in hydroxylation of proline and lysine Plays an important role in degradation of hemoglobin to bile pigments Enhances Iron absorption Essential in the synthesis of Serotonin
  53. Required for oxidation of P – hydroxyphenylpyruvate to homogentisic acid in tyrosine metabolism Reduces risk of Cancer, Cataract, Coronary Heart diseases Essential in the synthesis of Corticosteroid hormones, Immunoglobulins Essential for formation of tetrahydrofolate Involved in maturation of Erythrocytes
  54. Deficiency symptoms: • SCURVY – Spongy, Sore gums Loose teeth Anaemia Swollen joints Fragile blood vessels
  55. • Decreased immunocompetence • Delayed wound healing • Sluggish hormonal function of adrenal cortex and glands • Perifollicular haemorrhage with Corkscrew hair • Osteoporosis • Scorbutic tongue Treatment – 300mg/day – Children 500 – 1000/day – Adults for about 3 months or until resolution of clinical sequele
  56. THIAMINE (B1) • Anti Beri Beri, Anti Neuritic Vitamin • Water soluble • Has specific coenzyme – THIAMINE PYROPHOSPHATE – Associated with carbohydrate metabolism
  57. Dietary Sources: • Cereals • Oil seeds • Pulses • Nuts • Pork • Liver • Heart • Kidney • Milk
  58. RDA: • Adults - 1-1.5 mg/day • Children - 0.7 – 1.2 mg/day • 2 mg/day – Pregnancy Lactation Old age Alcoholism
  59. Biochemical Functions: Plays an important role in transmission of Nerve Impulse Most of the enzymes namely Pyruvate dehydrogenase, alpha - Ketoglutarate dehydrogenase, Transketolase – requires TPP in carbohydrate metabolism
  60. Deficiency Symptoms: • BERI BERI • Commonly seen in people consuming exclusively polished rice as staple food Symptoms: • Loss of appetite • Weakness • Nausea • Mental depression
  61. • Constipation • Peripheral Neuropathy • Irritability • Numbness in the legs Treatment - Adults – 1- 1.5 mg/day Children - 0.7 - 1.2 mg/day Pregnancy and Lactation – 2 mg/day
  62. • Neurological manifestations - Peripheral neuritis • Muscle weakness Difficulty in walking • Edema of legs, face, trunk, serous cavities • Breathlessness • Palpitations • Calf muscles slightly swollen • Systolic BP , Diastolic BP • Heart becomes weak Dry Beri Beri Wet Beri Beri
  63. Dry Beri Beri Wet Beri Beri
  64. RIBOFLAVIN (B2) • Water soluble vitamin • Takes part in various cellular oxidation – reduction reactions • Coenzymes – Flavin mononucleotide (FMN) Flavin Adenine dinucleotide
  65. Dietary sources: • Milk and its products • Eggs • Meat • Liver • Kidney • Cereals • Fruits • Vegetables • Fish
  66. RDA: • Adult – 1.2 – 1.7 mg/day • Requirement increases in Pregnancy and lactation
  67. Biochemical Functions: Flavin coenzymes – responsible for energy production by participating in many redox reaction Co enzymes are associated with enzymes involved in carbohydrate, lipid, protein and purine metabolism and electron transport chain
  68. Deficiency Symptoms: • Cheilosis • Glossitis • Dermatitis
  69. NIACIN (B3) • Pellagra preventive factor Coenzymes: 1) NAD+ 2) NADP+ Synthesized by essential amino acids - Tryptophan B3
  70. Dietary Sources: • Liver • Yeast • Whole grains • Cereals • Pulses • Milk • Eggs • Vegetables • Fish
  71. RDA: • Adults – 15 – 20 mg/day • Children – 10 – 15 mg/day 1 NE = 1 mg Niacin or 60 mg of Tryptophan
  72. Biochemical Functions: Coenzymes NAD+ and NADP+ involved in variety of Oxidation – Reduction reactions NADH – generates ATP by oxidation in Electron Transport Chain NADPH – important for many biosynthetic reactions as it donates reducing equivalents
  73. Deficiency Symptoms: • PELLAGRA – seen among people whose staple diet is corn or maize • Involves skin, GIT, CNS Symptoms: • 3D’s - Dermatitis – neck ( Casal necklace) dorsal part of feet, ankle, parts of face Diarrhoea – in the form of loose stools, often associated with blood and mucus Dementia – degeneration of nervous tissue – anxiety, irritability, poor memory, insomnia Death
  74. PYRIDOXINE (B6) • Represents 3 compounds – Pyridoxine Pyridoxal Pyridoxamine • Active form of B6 is the coenzyme – PYRIDOXAL PHOSPHATE (PLP)
  75. Dietary Sources: • Egg yolk • Fish • Milk • Wheat • Corn • Cabbage • Roots • Tubers
  76. RDA: • Adult – 2 -2.2mg /day • Pregnancy Lactation 2.5 mg/day
  77. Biochemical Functions: Pyridoxal phosphate participates in reactions like Transamination, Decarboxylation, Deamination, Transsulfuration, Condensation PLP – required for synthesis of delta – amino Levulinic acid Energy Releasing Vitamin – as it participates in Transamination reactions
  78. Deficiency Symptoms: • Pyridoxine deficiency is associated with neurological symptoms such as depression, irritability, nervousness, mental confusion • In children – there is drastically reduced GABA production Convulsions (epilepsy) • In severe deficiency – convulsions, peripheral neuropathy • Decrease in Hb levels, associated with Hypochromic microcytic anemia also seen Treatment – 10 – 100mg IV – Active seizures 25 – 600mg Orally – less serious or less acute presentations
  79. BIOTIN • Formerly known as Anti Egg White Injury Factor, Vitamin B7 or Vitamin H • It is a sulfur containing B complex vitamin • Directly participates as a coenzyme in the carboxylation reactions
  80. Dietary Sources: • Egg yolk • Tomatoes • Grains • Milk • Liver • Kidney
  81. RDA: • Adults – 100 - 300mg
  82. Biochemical functions: Gluconeogenesis and citric acid cycle Pyruvate oxaloacetate pyruvate carboxylase BIOTIN BIOTIN BIOTIN Fatty acid synthesis Acetyl coA Malonyl coA Acetyl co A carboxylase Propionyl coA Methylmalonyl coA Propionyl co A carboxylase
  83. Deficiency Symptoms: • Anaemia • Loss of appetite • Hair loss (alopecia) • Nausea • Dematitis • Glossitis • Depression, Hallucinations • Muscle pain
  84. PANTOTHENIC ACID • Formerly known as Chick Anti – Dermatitis • Widely spread vitamin • Coenzyme A
  85. Dietary Sources: • Eggs • Meat • Liver • Yeast • Milk
  86. RDA: • Adults – 5 – 10 mg/day
  87. Biochemical Functions: Involved in carbohydrate, protein and lipid synthesis Serves as a carrier of activated Acetyl or Acyl groups Involved in formation of Fatty acids Regarded as coenzyme of metabolic integration Succinyl coA involved in synthesis of porphyrins of Heme
  88. Deficiency Symptoms: • Deficiency manifestations – not reported in humans • Dr. Gopalan – linked Burning feet syndrome with B5 deficiency • Burning feet syndrome - Pain and numbness in the toes Sleeplessness Fatigue Treatment – Pantothenol or Calcium Pantothenate Symptoms resolves usually in 4 weeks
  89. FOLIC ACID • Vitamin B9 or Folacin • Water soluble vitamin • Active form of folic acid – Tetrahydrofolate (THF or FH4)
  90. Dietary Sources: • Green vegetables • Whole grains • Cereals • Liver • Kidney • Yeast • Eggs
  91. RDA: • 200 µg/day • 300 µg/day – Pregnancy and lactation
  92. Biochemical Functions: Tetrahydrofolate involved in one carbon metabolism THF serves as an acceptor or donor of one carbon units in reactions involving amino acid and nucleotide metabolism Amino acids like Glycine, Serine, Ethanolamine and Choline are synthesized N – Formylmethionine, the initiator of protein biosynthesis is formed
  93. Deficiency Symptoms: • Pregnant women, lactating women, and women on oral contraceptives, alcoholics are susceptible to folate deficiency • Impaired DNA synthesis – decreased production of Purines and Pyrimidines • Macrocytic anemia • FIGLU (Formiminoglutamate) accumulates and excreted in urine • Hyperhomocystenemia Treatment – 1-5 mg of folic acid per day Orally
  94. COBALAMIN (B12) • Anti – Pernicious Anemia Vitamin • Unique vitamin synthesized by only microorganisms • Coenzymes – 1) 5- deoxyadenosyl cobalamine 2) Methylcobalamin
  95. Dietary Sources: • Chicken • Pork • Fish • Eggs • Curd • Milk • Liver • Kidney
  96. RDA: • Adults - 3 µg/day • Children - 0.5 – 1.5 µg/day • Pregnancy Lactation 4 µg/day
  97. Biochemical Functions: Synthesis of Methionine from homocysteine Homocysteine Methionine Homocysteine methyltransferase Methylcobalamine Isomerization of Methylmalonyl coA to Succinyl coA Methyl Succinyl coA malonyl coA Methylmalonyl coA mutase Deoxyadenosyl cobalamine
  98. Deficiency Symptoms: • Deficiency of vitamin B 12 is seen among the strict vegetarians • Pernicious anemia • Neuronal degeneration and demyelination of nervous system Symptoms: 1) Paresthesia of fingers and toes 2) In advanced stages – confusion, loss of memory, psychosis • Impaired fatty acids synthesis • Excretion of methylmalonic acid in urine Treatment – 100 -1000 µg IM
  99. CONCLUSION • Vitamins are essential to our life. • First of all, vitamin is that component of a balanced diet, which the human body generally cannot be synthesized on its own. • So we must consume vitamins directly in the form of food or through supplements as tonic or tablets. • The whole process of assimilaton of vitamins depends on ingestion of food • Vitamins play an important role in normal health of oral structures especially fat soluble vitamins deficiency which affects hard tissues
  100. REFERENCES • Satyanarayana U et al. Biochemistry. 5th Edition. Kolkata: Books and Allied • Vasudevan DM et al. Textbook of biochemistry. 8th Edition: Jaypee • Newman et al. Carranza’s Clinical Periodontology. 11th Edition: Elsevier • Park. Park’s Textbook Of Preventive and Social Medicine. 24th Edition: Bhanot • Aparna Sheetal et al. Malnutrition and its oral outcome – A review. J Clin Diagn Res 2013, Jan 7(1): 178-180 • Abhishek Ghosh et al. Role of vitamins and diseases: An overview. Indian journal of applied research. 2015, December 12(5): 292-295
  101. • Aparna P et al. Vitamin D deficiency in India. J Family Med Prime Care. 2018, Mar- Apr 7(2): 324-330 • Rajiv Singala et al. Vitamin B12 deficiency is endemic in Indian population: A perspective from North India. Indian journal of Endocrinology and Metabolism. 2019, May 23(2): 211- 214 • Khan KM, Jialal I. Folic Acid (Folate) Deficiency. InStatPearls [Internet] 2018 Dec 17. StatPearls Publishing. • Bibile SW et al. Pantholenol and the Burning feet syndrome. British Journal of Nutrition. 1957, Dec 11(4): 434 – 439
  102. • Maxfield L, Crane JS. Vitamin C deficiency (scurvy). InStatPearls [Internet] 2019 Mar 18. StatPearls Publishing. • Brown MJ et al. Vitamin B6 Deficiency (Pyridoxine) in B6 Deficiency (Pyridoxine). InStatPearls [Internet] 2018 Oct 27. StatPearls Publishing.