1 VITAMINS “ VITAMIN” means “vital for life” VITAMINS are organic compounds which are...
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Transcript of 1 VITAMINS “ VITAMIN” means “vital for life” VITAMINS are organic compounds which are...
1
VITAMINS
• “VITAMIN” means “vital for life”
• VITAMINS are organic compounds which are necessary in small quantities (mg or µg Micronutrients) for everyday healthy functioning of the body
Active form
• The structural form that performs its function (exhibits activity) within the organism.
• Human cannot synthesize sufficient quantities of vitamins; thus, vitamins must taken from other sources (diet or pill) 2
The general symptoms of any vitamin deficiency
• Frequent illness• Slow healing wounds• tiredness
MACalvey/Teachnet/Vitamins 2006 3
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Water soluble• Have more oxygen and
nitrogen in their structure
• Cannot be stored in body - regular supply needed
• Excess is excreted in urine - no danger of toxic levels
• Unstable to heat and light, leach into cooking liquids
Fat Soluble• Have significant
hydrocarbon portions in their structure
• Can be stored in body - regular supply not needed
• Can accumulate to toxic levels if large amounts ingested
• Fairly stable at normal cooking temperatures
B Vitaminsare important for healthy skin and nervous system
• Vitamin B1 (thiamine)• Vitamin B2 (riboflavin)• Vitamin B3 (niacin or niacinamide)• Vitamin B5 (pantothenic acid)• Vitamin B6 (pyridoxine, pyridoxal, or pyridoxamine, or
pyridoxine hydrochloride)• Vitamin B7 (biotin)• Vitamin B9 (folic acid)• Vitamin B12 (various cobalamins; commonly
cyanocobalamin in vitamin supplements)
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In general, the B complex is important for healthy skin and nervous system
In general, the B complex is important for healthy skin and nervous system
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B complex Vitamins
Functions
• Essential for release of energy from arbohydrates (coenzyme)
• Necessary for appetite and good health
• Needed for normal functioning of nervous system
Deficiency
• Beri-beri disease of nervous system
Common in countries where polished rice is staple food
Vitamin B1 - Thiamine
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Vitamin B1 - Thiamine
RDA
1mg per day - Requirement increases with energy expenditure
RDA Recommended Daily Allowance
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Vitamin B2 -Riboflavin
Functions
• Metabolism of carbohydrates, proteins and fats (coenzyme FMN, FAD)
• Growth, repair, development of body tissues - healthy skin, eyes and tongue
• The principal growth promoting factor in the vitamin B complex
Deficiency• Loss of appetite• Swollen tongue,
cracked lips, eye infection, dermatitis
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Vitamin B3 -Niacin (Nicotinic acid)
Functions
• Metabolism of carbohydrates, proteins and fats (coenzyme NAD,NADP)
• Needed for normal functioning of nervous system
Deficiency• Pellagra Symptoms • loss of appetite • mental disorder
diarrhea • possible death
MACalvey/Teachnet/Vitamins 2006 15
Vitamin B 3 -Niacin (Nicotinic acid)
SourcesLiver meatYeast extractsMilkCheeseVegetablesgrains
MACalvey/Teachnet/Vitamins 2006 16
*RDA
15 - 20mg per day
Vitamin B3 -Niacin (Nicotinic acid)
*Related to protein intake
*Related to protein intake
MACalvey/Teachnet/Vitamins 2006 17
Vitamin B6 -Pyridoxine
Functions
• Protein metabolism (coenzyme)
• Involved in formation of haemoglobin, hormones and structural proteins
• Healthy development of nervous system
Deficiency• Tiredness and
Fatigue, irritability
• Premenstrual tension
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Vitamin B12 - (CyanoCobalamin)
FunctionsVit B12 is necessary for
the
• Red blood cell formation
• nervous system function
• the prevention of certain forms of anaemia and neurological disturbances
• functions primarily as a coenzyme in intermediary metabolism
Deficiency• Pernicious anaemia• Nerve degeneration
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Vitamin B12 - (CyanoCobalamin)
Sources• Meat Liver• Fish• Cheese• CerealsThis vitamin is stable to
cooking
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Vitamin B9 -Folic AcidFunctions
• Red blood cell formation
• Essential for synthesis of DNA and RNA (coenzyme)
• Development of brain, spinal cord and skeleton in foetus
Deficiency• Fatigue in mild
cases• Anaemia in severe
cases
Important to take folic acid prior to pregnancy and vital during first 3 months pregnancy
Important to take folic acid prior to pregnancy and vital during first 3 months pregnancy
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Pantothenic acid
Functions• Nessessary for the
biosynthesis of coenzyme A
Deficiency• Unknown
SourcesPantothenic derives from Greek word meaning from every where
Pantothenic derives from Greek word meaning from every where
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Biotin
Functions• A coenzyme important in
lipid and carbohydrates metabolism.
Deficiency• Unknown
SourcesBacteria in the intestine synthesize biotin in sufficient quantities
Bacteria in the intestine synthesize biotin in sufficient quantities
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Vitamin C -Ascorbic Acid
Functions• Formation of connective
tissue, collagen• Critical to immune system• Helps absorption of iron• Prevents scurvy• Promotes healing of
wounds and healthy blood vessels
• Acts as antioxidant, protects HDL cholesterol
Deficiency• Weakening of
connective tissue• Susceptibility to
infection• Incomplete iron
absorption• Delayed healing of
wounds
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Vitamin C -Ascorbic Acid
Sources• green peppers• Kiwi• Citrus fruits,
strawberries, • Spinach• broccolli
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Properties• Acts as an antioxidant
RDA
30-60 mg per day
Vitamin C -Ascorbic Acid
Least stable of all vitamins
Least stable of all vitamins
MA Calvey/Teachnet/Vitamins 2006 31
FAT SOLUBLE VITAMINS
Vitamins A,D,E,K
• Functions
• Effects of deficiency
• Sources
• RDA
Vitamin A - Retinol and Beta-Carotene
Retinol
Named because of its concern with retina of eye
Only found in animal foods
Retinol
Named because of its concern with retina of eye
Only found in animal foods
Beta-Carotene
Present with chlorophyll in plants, converted to Vitamin A in gut wall
Beta-Carotene
Present with chlorophyll in plants, converted to Vitamin A in gut wall
Vitamin A - Retinol and Beta-Carotene
Functions• Important to vision Necessary for production of
Rhodopsin - pigment in retina, helps eye adapt to dim light
• Regulates growth• Promotes healthy skin• Maintenance of healthy epithelial tissues
Effects of deficiency• Night blindness• Retarded growth,
malformed bones• Dry mucous membranes• Xerophthalmia - dry eye
membrane• Susceptibility to infection
CaroteneGo for Color!
Think Yellow, Orange,Red, Deep Green
Vitamin A - Retinol and Beta-Carotene
SourcesRetinol - liver oil,
Liver, Dairy products, Egg yolk
Beta-Carotene Dark green leafy vegetables, Broccoli, Carrots, Deep orange
fruits and vegetables
Vitamin A - Retinol and Beta-Carotene
Properties• Powerful antioxidant
RDA
600 µg per day
90% of Vitamin A in the body is stored in the liver
Vitamin D - Calciferols
Formed by action of ultra violet light on fungi and yeasts
Manufactured synthetically for use as vitamin supplement
Cholecalciferol
The sunshine Vitamin!
The sun activates Provitamin 7 dehydro cholesterol present in
fat under skin
Ergocalciferol
Provitamin 7 dehydro cholesterol
Cholecalciferol
Provitamin 7 dehydro cholesterol
Cholecalciferol
Vitamin D -Calciferols
Functions• Absorption and
laying down of calcium and phosphorous in bones and teeth
• Regulates calcium balance between bones and blood
• Prevents rickets
Effects of deficiency• *Rickets in children and
*osteomalacia in adults
• **Osteoporosis
• Dental caries
* Conditions where bones are soft and cannot weight of body
* Conditions where bones are soft and cannot weight of body
**Bones become light, less dense and prone to fractures
**Bones become light, less dense and prone to fractures
Vitamin E -Tocopherols
Functions• Powerful antioxidant• May reduce risk of heart disease, stroke,
cancer• Improves absorption of vitamin A
Effects of deficiency• Deficiency is rare• Linked to conditions
associated to malabsorption of fat
Anti coagulants and anti oxidants
Anti coagulants and anti oxidants
Vitamin E -Tocopherols
Properties
• Acts as antioxidant, delays rancidity and oxidation
RDA
Based on polyunsaturated fatty acid intake
Vitamin K
Functions
• Constituent of prothrombin which is necessary in blood clotting
Effects of deficiency• Abnormal clotting,
bleeding and haemorrhaging
• Deficiency is rare because intestinal bacteria produce sufficient quantities
Sometimes called “Coagulation” vitamin
Sometimes called “Coagulation” vitamin
Vitamin K
Sources• Dark green
vegetables• Liver• Lean meat• Eggs• Manufactured by
bacteria in intestine
RDANo established recommendation