vitamins kpk sh
TRANSCRIPT
VitaminsVitaminsBy
Komal and Hussain
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. He coined the term vitamine (in greek vita- life).
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
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.
Vitamin A: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 canyield two molecules of vitamin A*
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
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
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
• Teratogen
Vitamin D
body can make› from sunlight› precursor made from cholesterol
not essential 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
toxicity› most common in vitamin D› excess vitamin D = increase in blood
calcium = stones or hardening of blood vessels
sourcessources› fortified food: milk, margarine, cereals, beef, fortified food: milk, margarine, cereals, beef,
eggseggs
antioxidant› defender against free radicals
polyunsaturated fatty acids may reduce the risk of heart disease deficiencies› rare› erythrocyte hemolysis
preemies – destruction of red blood cells toxicity› rare› may interfere with blood-clotting
mechanisms of vitamin K widespread in food› easily destroyed by heat processing
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
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
Scurvy: characterised by spongy and sore gums, loose teeth , anaemia, swollen joints, fragile blood vessels, decreased immunocompetency, delayed wound healing, hemorrhage, osteoporosis etc.
B VitaminsB Vitamins
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.
Coenzymes
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
1998 adequate intake (AI)
› Adults: 5 mg/day Chief functions in the body
› Part of coenzyme A, used in energy metabolism
Easily destroyed by food processing Deficiency leads to burning feet
syndrome.
Widespread in foods
Organ meats Mushrooms Avacado Broccoli Whole grains egg liver, meat,
milk
1998 adequate intake (AI)
› Adults: 30 µg/day Chief functions in the body
› Part of a coenzyme used in energy metabolism, fat synthesis, amino acid metabolism, and glycogen synthesis
Significant sources
›Widespread in foods› Also produced by GI bacteria
Widespread in foods
Organ meats, fish
Egg yolks Soybeans Whole grains
Controversial other dietary compounds Still under scientific investigation May be “conditionally” essential Supplements NOT necessary Widespread in foods
Choline› Contains N2; made from methionine
› Used to make lecithin & acetylcholine
› Adequate Intake (AI) established 1998 Men=550 mg/day; Women=425 mg/day
Inositol› Part of cell membrane structure
Carnitine› Transports long-chain fatty acids
Not essential for humans; essential only for bacteria or other forms of life
PABA (para-aminobenzoic acid)
Vitamin P (hesperidin)-a bioflavonoid Ubiquinone (Coenzyme Q10)
Pyrroloquinoline quinone (methoxatin) Orotic acid Lipoic acid
Vitamin O (oxygenated salt water) Vitamin B15 (Pangamic acid)
Vitamin B17 (Laetrile)
› Alleged “cancer cure”
› Potentially dangerous
Vitamin B5
› Simply another name for Pantothenic Acid
Good friends are like stars, you don’t always see them –
but you know they are there.