2. Introduction:
Vitamins may be regarded as organic
compounds required in the diet in small
amounts to perform specific biological
functions for normal maintainance of optimum
growth and heath of an organism.
Hopkins coined the term ‘accesory factors’ to
the unknown and essential nutrients present in
the natural foods.
Funk in 1913 isolated an active principle (an
amine) from the rice polishing and later in
yeast, which could cure beri-beri in pigeons.
3. Classification:
Mainly classified as
1) Fat soluble - includes Vit. A,D,E,K
2) Water soluble- further classified as,
a) Non- B complex
i) Vit. C
b) B complex
i) Energy releasing – includes B1,B2,B3,B6,B7 and
Pantethonic acid
ii) Hematopoietic – includes Vit. B12 and folic acid
4. Fat Soluble Vitamins
Fat soluble vitamins include: A and carotenoids, E, K, D
Associated with fat absorption.
Needed in small amounts.
Stored in fatty tissues.
Excess intake has toxic consequences.
5. 3 forms in the body-retinol,retinal,retinoic acid
collectively known as retinoids
– found in food derived from animals
Retinol, the alcohol form Retinal, the aldehyde form Retinoic acid, the acid form
Beta-carotene, a precursor
Cleavage at this point can
yield two molecules of vitamin A*
Vitamin A:
6. precursor: beta-carotene
derived from plant foods
can split and form retinol in intestine and liver
promote vision
maintain epithelial tissue and skin
mucous membranes
support reproduction and growth
sperm development
fetal development
deficiency
infectious disease-pneumonia, measles, diarrhea
Keratinization -dry, rough, scaly skin
night blindness
7. • Deficiency leads to night blindness
• Toxicity
– yellow skin: too much beta-carotene
• excess stored under skin in fat
– weaken bones
• Found in
– colorful vegetables
– Liver, kidney, egg yolk
– milk, cheese, butter
– Carrot, pumpkin, mango
– papaya, spinach
8. Deficiency:
• increased morbidity in children under age 5 with no evident
clinical signs of deficiency
• Signs, when present include xeropthalmia, anorexia,
retarded growth, increased susceptibility to infections,
enlargement of hair follicle, and keratinization of epithelial
(mucous cells) of the skin.
Toxicity:
• Hypervitaminosis A
• Nausea, vomiting, double
vision, headache,
dizziness, and
desquamation of the skin
9.
10. Body can make
– from sunlight
– precursor made from cholesterol
• Production occurs in liver and kidney
– diseases can affect activation
• target tissue
– intestines, kidneys, bones
• Part of the bone-making/maintenance team
– maintains blood concentrations of Ca & P
• Deficiencies
– ultimately creates a calcium deficiency
VITAMIN D
12. • Toxicity
– most common in vitamin D
– excess vitamin D = increase in blood calcium =
stones or hardening of blood vessels
• sources
– fortified food: milk, margarine, cereals, beef, eggs
13.
14.
15. antioxidant
defender against free radicals
polyunsaturated fatty acids
may reduce the risk of heart disease
Deficiencies are rare
erythrocyte hemolysis
widespread in food
easily destroyed by heat processing
16.
17.
18. VITAMIN-K
aids in blood clotting
deficiency causes hemorrhagic disease
toxicity
not common
sources
made by bacteria in GI tract
absorbed and stored in liver
½ of needs
liver is also high in vitamin K
19.
20.
21.
22. Vitamin C: (Ascorbic acid)
Dietary sources: citrus fruits, amla , guava, green
vegetables(Cabbage, spinach) , tomatoes, potatoes.
Biochemical functions:
Collagen formation
bone formation
iron and hemoglobin metabolism
tryptophan metabolism
reduces risk of cataract
increase phagocytic action of leucocyte
23.
24.
25. Deficiency
Scurvy
characterised by spongy and sore gums, loose teeth ,
anaemia, swollen joints, fragile blood vessels,
decreased immunocompetency, delayed wound
healing, hemorrhage, osteoporosis etc.
28. Muscles and
other tissues
metabolize
protein.
Brain and
other tissues
metabolize
carbohydrates.
Bone tissues
make new
blood cells.
Liver and other
tissues
metabolize fat.
Digestive
tract
lining
replaces
its cells.
34. Niacin-B3
Chief functions in the body
Part of coenzymes NAD (nicotinamide adenine
dinucleotide) and NADP (its phosphate form) used in
energy metabolism
Toxicity symptoms
Painful flush, hives, and rash (“niacin flush”)
Excessive sweating
Blurred vision
Liver damage, impaired glucose tolerance