for medical students

1. The Water Soluble
Vitamins & Trace
elements
Dr.Parvathy
Dept. of Pathology

2. B Complex Primary
Functions
Energy metabolism
 Thiamin (B-1), Riboflavin (B-2), Niacin (B-
3), Pyridoxine (B-6), Biotin, Pantothenic
Acid
Red blood cell synthesis
 Folate, B12
Homocysteine metabolism
 Folate, B12, B6

3. Enrichment Act of 1941
and 1998
Many nutrients lost through milling
process of grains
Grain/cereal products are enriched
Thiamin, riboflavin, niacin, folate, iron
Whole grains contain original nutrients
Enriched grains still deficient in B-6,
magnesium and zinc

4. Thiamin (B1)
Thiamine Functions:
Synthesis of ATP
Co-factor in pentose phosphate
pathway
Maintains neural membranes and
conduction

5. Deficiency of Thiamin
Occurs where polished rice is the only
staple
Chronic alcoholics
Little stored in body, so alcoholic binge of 1-
2 weeks may result in deficiency
Pernicious vomiting or diarrhea
• Wernicke-Korsikof f Syndrome
– Wernicke encephalopathy
• Korsakoff’s psychosis
• Result of thiamine deficiency caused by alcoholism

6. Beriberi (I can’t I can’t)
 Weakness, nerve degeneration, irritability,
poor arm/leg coordination, loss of nerve
transmission
 Edema, enlarged heart, heart failure
 Symptoms due to poor metabolism of
glucose
 Depression and weakness can be seen
after only 10 days on a thiamin-free diet

7. Wet and Dry BeriBeri

8. Food Sources of Thiamin
Green beans, milk, orange juice, organ
meats, peanuts, dried beans and seed
Enriched breads and grains/ whole grains
Thiaminase found in
raw fish Destroys thiamin

9. RDA For Thiamin
1.1 mg/day for women
1.2 mg/day for men
Surplus is rapidly lost in urine; non
toxic; no Upper Level

10. Riboflavin (B2)
Riboflavin is a critical component of
flavin mononucleotide (FMN) & flavin
dinucleotide (FAD) which participate in
redox reactions

11. Ariboflavinosis

12. Food Sources of
Riboflavin
Milk/products
Enriched grains
Ready to eat cereals
Liver
Vegetables (asparagus,
broccoli, greens)
Sensitive to uv radiation
(sunlight)
Stored in paper, opaque plastic containers

13. RDA for Riboflavin
1.1 mg/day for women
1.3 mg/day for men
Average intake is above RDA
Toxicity not documented
No upper level

14. Niacin (B3)
Nicotinic acid and nicotinamide
Essential component of NAD & NADP
which play central roles in cellular
intermediate metabolism.
Synthetic pathways require niacin, especially
fatty acid synthesis

15. Deficiency of Niacin:
3 Ds Pellagra
Dermatitis - which most often occurs in
sun exposed areas of face and upper
extremity
Dementia - results from neuronal
degeneration in the brain and spinal
column
Diarrhea - is associated with edema and
inflammation of the intestinal submucosa.
Poor appetite, weight loss, weakness

16. Pellagra

17. Food Sources of Niacin
Enriched grains, ready to eat cereals
Beef, chicken, turkey, fish
peanuts
Heat stable; little cooking
loss

18. RDA for Niacin
14 (mg) NE/day for women
16 (mg) NE/day for men
Upper Level is 35 mg
Other names
Nicotinic acid, Nicotinamide,
Niacinamide,Vitamin B3
Precursor: dietary tryptophan(60mg=1mg)
Toxicity S/S: headache, itching, flushing,
liver and GI damage

19. Pantothenic Acid/ Vit B5
Part of Coenzyme-A
Essential for metabolism of CHO, fat,
protein
Deficiency rare
No known toxicity

20. Food Sources of
Pantothenic acid
“From every side”
Meat
Milk
Mushroom
Liver
Peanut
Eggs
Adequate Intake= 5 mg/day
Daily Value 10 mg
Average intake meets AI

21. Biotin
Free and bound form
Metabolism of CHO and fat
Assists the addition of CO2 to other
compounds
Synthesis of glucose, fatty acids, DNA
Help break down certain amino acids

22. Biotin Deficiency
Raw egg whites avidin bind biotin →
deficiency
Requires large amount
Scaly inflamed skin, tongue, and lip
changes
Poor appetite, nausea, vomiting
Anemia
Muscle pain and weakness
Poor growth

23. Food Sources of Biotin
Cauliflower, yolk, liver,
peanuts, cheese
Intestinal synthesis of
biotin

24. Biotin Needs
Adequate Intake is 30 ug/day for adults
Deficiency rare
No Upper Level for biotin
Relatively nontoxic

25. Pyridoxine (B6)
Coenzyme
Activate enzymes needed for
metabolism of CHO, fat , protein
Synthesize nonessential amino acid via
transamination
Synthesize neurotransmitters
Synthesize hemoglobin and WBC

26. Pyridoxine/B6
Deficiency
Widespread symptoms
• Depression
• Vomiting
• Scaly dermatitis
• Nerve irritation
• Impaired immune system

27. Food Sources of Vitamin
B-6
Well absorbed
• Meat, fish, poultry
• Enriched cereals
• Potatoes
• Milk
Less well absorbed
• Fruits and vegetables:
Banana, spinach
Heat and alkaline sensitive

28. B6 Toxicity
Nerve damage
Difficulty walking
Numbness in hands/feet
Can lead to irreversible nerve damage
with > 200 mg/day
Upper Level set at 100 mg/day

29. RDA for Vitamin B-6
1.3 mg/day for adults
1.7 mg/day for men over 50
1.5 mg/day for women over 50
Average intake is more than the RDA
Athletes may need more
Alcohol destroys vitamin B6

30. Folate
 Part of coenzymes THF
(tetrahydrofolate) and DHF
(dihydrofolate) used in DNA synthesis
and therefore important in new cell
formation-Anticancer drug methotrexate
 Homocysteine metabolism
 Neurotransmitter formation

31. Deficiency of Folate
Similar signs and symptoms of vitamin
B-12 deficiency
Anemia
Pregnant women
Alcoholics
Megaloblastic Anemia

32. Neural Tube Defects

33. Food Sources of Folate
Liver
Fortified breakfast cereals
Grains, legumes
Foliage vegetables
Susceptible to heat,
oxidation, ultraviolet light
Synthetic form better
absorbed

34. RDA for Folate
400 ug/day for adults
(600 ug/day for pregnant women)
Excess can mask vitamin B-12
deficiency
Upper Level set at 1 mg

35. Cobalamin/Vitamin B-12
Synthesized by bacteria, fungi, and
other lower organisms
Role in folate metabolism
Maintenance of the myelin sheaths
RBC formation
Part of coenzymes methylcobalamin
and deoxyadenosylcobalamin used in
new cell synthesis

36. Absorption requires
HCl
Pepsin
Intrinsic factor
Difficult for vegetarians to obtain
Pernicious anemia
 Nerve degeneration, weakness
 Tingling/numbness in the extremities (parasthesia)
 Paralysis and death
 Looks like folate deficiency
Usually (95%) due to decreased absorption
ability

37. Vitamin B12 deficiency
Diagnosis: Schilling test
Treatment: 1000mg Vitamin B12 IM
daily for two weeks and monthly injections
for life
High Risk: African Americans, northern
Europeans, elderly

38. Food Sources of Vitamin
B-12 and algae
Synthesized by bacteria, fungi
Animal products, meat
Seafood
Eggs
Milk

39. RDA for Vitamin B-12
2.4 ug/ day for adults and elderly
adults
B-12 stored in the liver
Non-toxic (no Upper Level)

40. Vitamin C
Synthesized by most animals (not by
humans)
Decrease absorption with high intakes
Excess excreted

41. Functions of Vitamin C
Reducing agent (antioxidant)
Iron absorption (enhances)
Synthesis of collagen
Immune functions
Wound healing

42. Antioxidant
Can donate and accept hydrogen
atoms readily
Water-soluble
Needs are higher for smokers
May prevent certain cancers
(esophageal, oral, stomach cancer,
cardiovascular disease, cataracts)

43. Vitamin C Deficiency:
History of Scurvy
Sailors on long sea voyages suffered horribly
from scurvy
On Vasco da Gama's voyage to the East Indies
in 1497, 100 out of 160 men were lost from the
disease.

44. Scurvy in the British
James Lind
Royal Navy
published his
Treatise on the
Scurvy in 1754.
Lime juice was
made mandatory
on British Navy
sailing ships 40
years later

45. Deficiency of Vitamin C
Scurvy
 Deficient diet for 20-40 days
 Fatigue, pinpoint hemorrhages
 Bleeding gums and joints. Hemorrhages
 Associated with poverty; macrobiotic diet
Rebound Scurvy
 Suddenhalt to high levels of vitamin C
supplements

46. Scurvy
Scorbutic Rosary
Follicular
Hemorrhages

47. Food Sources of
Vitamin C
Citrus fruit Easily lost through
Potato cooking
Green pepper Sensitive to heat
Cauliflower
Broccoli
Strawberry
Spinach

48. RDA for Vitamin C
90 mg/day for male adults
75 mg/day for female adults
+35 mg/day for smokers
Upper Level is 2 g/day

49. Vitamin C Excess
Hemochromatosis
Oxalate kidney stones
Erodes tooth enamel

50. Choline
Newest essential nutrient
Grouped with B group vitamins
All tissues contain choline
Precursor for acetylcholine
(neurotransmitter)and
phospholipids
Some role in homocysteine
metabolism

51. Food Sources of Choline
Widely distributed
Milk
Liver
Eggs
Peanuts
Lecithin added to food
Deficiency rare

52. Trace Elements
Essential Trace Elements:
iron, zinc, copper, cobalt, chromium,
fluorine, iodine, manganese,
molybdenum and selenium
Probably essential:
nickel, tin, vanadium, silicon, boron

53. Copper
Metabolism
• Copper circulates bound to ceruloplasmin
• Excretion occurs via transport of copper into bile
and elimination in feces

54. cofactor for many cuproenzymes including:
•Cu, Zn-superoxide dismutase (antioxidant)
•Cytochrome C oxidase (ATP synthesis, neurologic
function)
•Ceruloplasmin (6 atoms per molecule)
•Lysyl oxidase (cross links and stabilizes connective
tissue proteins)
•Tyrosinase (melanin synthesis)

55. Copper Physiology/Deficiency
• Acquired deficiency is rare
• Manifestations:
Hypochromic microcytic anemia
Neutropenia
Hypopigmentation of hair and skin
Structural abnormalities in connective tissue
Fetal and neonatal deprivation leads to neurologic
dysfunction
Reduced levels of circulating copper and ceruloplasmin

56. Food Sources
organ meats, seafood, nuts, seeds,
cereals, whole grains, cocoa
Inborn Errors of Copper Metabolism:
Wilson’s Disease (Hepatolenticular
Degeneration)
Menkes Kinky Hair Syndrome

58. Pili torti (Menkes Disease)

59. Iodine
-body normally has 20-30 mg of iodine
and more than 75% is in the thyroid
gland
-the rest is in the mammary gland,
gastric mucosa, and blood
-it’s only function is related to thyroid
hormone

60. Food Sources
foods of marine origin (seaweed),
processed foods, iodized salt

61. Deficiency
-goiter—enlargement of the thyroid
gland
goitrogens -cabbage, turnips, peanuts,
soybeans
-deficiency may be absolute—in areas
of deficiency, or relative—adolescence,
pregnancy, lactation
-goiters are more prevalent in women
and with increased age

62. Endemic Cretinism
severe deficiency during
gestation and early
postnatal growth:
cretinism
(mental deficiency, spastic
diplegia, quadriplegia,
deaf mutism, dysarthria,
shuffling gait, short
stature, hypothyroidism)

63. Iodine deficiency is the most
common nutrient deficiency
in the world!

64. Iodine Excess and Toxicity
Humans are remarkably tolerant to high
iodine intakes
In iodine deficiency, repletion must be
done slowly to prevent hyperthyroidism

65. Goiter
Endemic to parts of
S. America and India
Sporadic cases in U.S.
Selenium deficiency
(needed to convert T4 to T3)

66. Goiter -
Complications
Usually asymptomatic
Acute pain from thyroidal
hemorrhage
Dysphagia
Dyspnea

67. Chromium
Regulation of glucose metabolism as a
component of glucose tolerance factor
(GTF).
GTF increases effect of insulin (by facilitating
its binding to cell receptor site).
Chromium regulates plasma lipoprotein
concentration.
Reduces serum cholesterol and serum
triglycerides.
Both chromium and Fe are carried by Tf,
however albumin can also assume this role

68. Food Sources
bread, meats, poultry, fish, beer

69. Deficiency
altered CHO metabolism, impaired glucose
tolerance, glycosuria, fasting hyperglycemia,
increased insulin levels and decreased insulin
binding to receptors
-impaired growth, peripheral neuropathy,
negative nitrogen balance
Toxicity
chronic renal failure

70. Cobalt
-most stored with vitamin B12
-component of B12—cobalamin
-essential for maturation of RBC’s and
normal function of all cells

71. Deficiency
-**macrocytic anemia
Toxicity
polycythemia
-hyperplasia of BM
-reticulocytosis
-increased blood volume

72. Selenium
-glutathione peroxidase
• --overlaps with vit E for antioxidant
effects
• Iodothyronine 5’- deiodinase
• Thioredoxin reductase
• Epidemiologic evidence indicates low intakes of
Se are associated with higher risk of prostate
cancer

73. Food Sources
Food content tends to follow Se content of soil –
richest food sources are organ meats and sea foods,
followed by cereals and grains, dairy products, fruits
and vegetables
• Requirements determined based on serum glutathione
peroxidase activity

74. Selenium Deficiency Diseases
•Human deficiency is rare except in areas with low Se
content in soil
Keshan disease occurs in Keshan China: endemic
cardiomyopathy and muscle weakness (due to oxidized lipids)
Aggressive supplementation has eliminated disease
•Iatrogenic deficiency
TPN without supplemental Se

75. Selenium Toxicity
Acute-cardiorespiratory collapse
(gram amounts)
Chronic (selenosis) -changes in
nail structure and loss of hair
(intakes ~6x UL)

76. Molybdenum
-relationship with copper and sulfate
-cofactor of many enzymes involved in
the catabolism of sulfur AA, purines and
pyridines
-Toxicity: gout-like syndrome,
reproductive SE’s
-Deficiency: increased risk with co-
existing copper deficiency, TPN

77. Manganese
•High concentration of Mn2+ is present in mitochondria
• Functions as a necessary factor for activation of
glycosyltransferases (enzymes responsible for the
synthesis of oligosaccharides, glycoproteins,
proteoglycans.
• Required for superoxid dismutase activity, for
activity of metalloenzymes:
hydrolases
kinases
decarboxylases
transferases.
Deficiency of Mn extensively reduce glycoprotein and
proteoglycan formation.

78. Iron
 Adult human body contains 3-4 Gm
 60-70% is present in Blood and rest in storage
form.
 Each Gm of Hb contains 3.34mg of Iron.
Requirement :
 1 mg per day for Male
 2.5 mg for Females
 3.5 mg for Females in Physiological stress
conditions

79. Sources of iron
 Haem Iron:
 Liver, meat, poultry, Fish
 Non Haem Iron:
 Cereals, GLV, Legumes,, Nuts, Oil seeds,
Dried Fruits, Jaggery
 Factors interfere in absorption are
enzymes in the food – Phytates, Oxalates,
Phosphates, Dietary fibres
 Ascorbic acid is the most potent enhancer
iron

80. Iron Deficiency
 Occurs in 3 stages:
 First Stage: Decreased storage without any
other detectable abnormalities
 Second Stage: stores are exhausted, serum
Ferritin level decreases.
 Third Stage: Decrease in Hemoglobin
percentage
 Functional disturbances: decrease in
resistance to infection, increase morbidity &
mortality, decreased work performances,
impaired cell mediated immunity

81. Evaluation of iron
1.
status relative index of
Hemoglobin Concentration:
iron deficiency. ( early Anemia if Hb is 10-
11g% & marked anemia Hb is < 10g%).
2. Serum Iron concentration: useful index
( Normal 0.8 to 1.8mg /L)
3. Serum Ferritin level: Gold standard &
sensitive tool for evaluation and reflects the
size of the iron status ( < 10Micrgms/L)
4. Serum Transferrin Saturation: 16% - 30%

83. Correction of Iron
Deficiency
 Oral iron supplements
 100-200 mg elemental iron daily
 Higher doses are of no benefit
 Ferrous sulphate 65mg/tab
 Pregnant women- 100mg/tablet
(+ folic acid)

84. Fluorine
 It is found in combined forms
 96% of fluorides in the body found in bone and
teeth.
 An essential for normal mineralisation of bones
and formation of dental enamel
Source:
 Drinking water : Fluorine in the drinking water is
0.5 mg per ltr. Excess of fl > 3mg causes
flourosis.
 Foods: Sea fish, cheese, Tea
 It is a two edged sword ( deficiency or excess)

86. Zinc
 Adult body contains 1.4 to 2.3 gms of Zinc
 Plasma level- 96Microgm per 100 ml ( adults), 89
Microgram per 100 ml (children)
 Functions are
 Active role in metabolism of glucose and proteins
 Synthesis of insulin by pancreas
 Immunity functions
 Food sources :
 meat, milk, fish
 Plant sources have low bioavailability

87. Zinc deficiency
1. Growth failure
2. Sexual infantilism in adolescents, loss of taste,
delayed wound healing, decrease in
immunosynthesis.
3. Spontaneous abortions, stillbirths, congenital
malformations, anencephaly
4. LBW, Intra Uterine deaths, premature labour.
5. Requirement is 15mg for men
6. 12 mg for women, 10mg for children