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132
Vitamins
Vitamins are special chemicals found in food.
Vitamins
Vita = Life
Amine = Containing Nitrogen
The First Vitamin Discovered Contained Nitrogen
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Vitamins
OrganicEssential NutrientsRequirements Minute (Small)Perform Specific Functions
GrowthReproductionMaintenance of Health and Life
Vitamins are organic substances which the body require in small amounts to perform specific functions that promote growth, normal metabolism, reproduction and normal maintenances of health and life.
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Vitamins
Vitamins Differ from Energy-Yielding Nutrients such as Carbohydrate, Proteins and Fat
Structure
Function
Food Contents
Vitamins do not supply energy but are essential to metabolic activities and help in the utilization to the proximate principles.They are also involved in the utilization of the major nutrients like proteins, CHO & fats.
Vitamins Similar to Energy-Yielding Nutrients: Carbohydrate, Protein and Fat
Vital to Life
Organic
Vitamins
Vitamins
Available in Foods
OrganicDestructible:
Light: Riboflavin (B2)
Oxygen: Vitamin C
Heat : Thiamin (B1) and Vitamin C
Vitamins
Solubility:Hydrophilic: (Water-Soluble)
Carbohydrate, Protein
Vitamins B and C
Hydrophobic: (Fat-Soluble)Fat
Vitamins A, D, E, K
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Precursors
Provitamins Inactive Vitamin Form
Chemically Changed to Active Form of Vitamins
Substances that occur in foods which are not themselves vitamins, but are capable of conversion into vitamins in the body e.g; carotens are the pro-vitamin of vitamin A.
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Riboflavin-Vitamin B2
FunctionsCoenzymes FMN and FAD
Energy Metabolism
Supports Normal Vision
Supports Skin Health
Food Sources
Vitamin is a precursor of two enzymes—Flavin-mononucleotide & Flavin adenine di-nuleotied.Release of energy from foods as it effects growth and cellular metabolismNeeds in normal vision and may help against cataract.Sources– Milk, eggs, organ meat, mushrooms, shellfish, cereals and pulses.
Riboflavin-Vitamin B2
Deficiency DiseaseAriboflavinosis
Deficiency SymptomsSkin RashCracks and Redness of MouthSensitivity to Light
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Niacin-Vitamin B3
FunctionsCoenzymes NAD and NADP
Energy Metabolism
Nervous System
Digestive System
Food Sources
NAD & NADP- are the active form of niacin named as nicotinamide adenine dinucleotide and nicotinamide adenine dinucleotide phosphate.-These coenzymes are involved in more than 50 different metabolic reactions.-Extracts energy from CHO and glucose.-proper nervous system functioning.Sources- Organ meats, liver, poultry, fish, milk, eggs, wheat germ, whole wheat, yeast.
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Niacin-Vitamin B3
Deficiency DiseasePellegra
Deficiency Symptoms
-A clinical condition due to niacin deficiency, characterized as 3Ds.-Weakness, irritability, burning tongue as the mucous membrane of the mouth is inflamed.-High doses results in irritation of the gastrointestinal tract.
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Biotin
Food Sources
Originally called vitamin H.Egg, liver, kidney, yeast, pulses, nuts, chocolates, cauliflower and green vegetables.
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Biotin
FunctionsCoenzyme
Energy Metabolism
Fat Synthesis
Amino Acid Metabolism
Glycogen Synthesis
--Biotin coenzyme participate in the metabolism of fat and CHO in the synthesis of fatty acids and amino acids.--Helps metabolize proteins, fats and CHO & thus helps to produce energy in body cells.--Assists in the synthesis of FA.--Incorporate AA into proteins & help with the formation of DNA & RNA.
Biotin
Deficiency SymptomsLoss of Appetite and Nausea
Abnormal Heart Action
Depression
Muscle Pain and Weakness
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Pantothenic Acid-Vitamin B5
Food Sources
Sources– Whole grain cereals, vegetables, peanuts, cheese, eggs-yolk, organ meats.
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Pantothenic Acid-Vitamin B5
FunctionsCoenzyme A
Energy Metabolism
This vitamin is a constituent of co-enzyme A and is present in all living matter.Important for cellular metabolism of CHO & fats to release energy.
Pantothenic Acid-Vitamin B5
Deficiency Symptoms
Insomnia
Fatigue
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Pyridoxine-Vitamin B6
FunctionsCoenzymes PLP and PMPAmino Acid MetabolismFatty Acid MetabolismConverts Tryptophan to Niacin
Food Sources
Pyridoxine and its co-enzymes have a wide variety of metabolic functions especially—-AA metabolism and its transportation.-Production of antibodies, RBC, synthesis and functioning of both DNA & RNA.- Fish, poultry, egg yolk, soya- bean, bananna, potatoes, cauliflower.
Pyridoxine-Vitamin B6
Deficiency DiseaseAnemia (small-cell type)
Due to the deficiency of B6 , the RBCs are pale and small and the Anemia is said to be Hypochromic and Microcytic.
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Folate-Folic Acid-Folacin
Functions
DNA Synthesis
New Cell Formation
Food Sources
Sources– Spinach, liver, peas, sweet potato, bean sprout, wheat germ, soya flour, milk, fruits.
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Folate-Folic Acid-Folacin
Deficiency DiseaseAnemia (large-cell type)
Deficiency SymptomsDiarrhea
Depression/Mental Confusion
-Deficiency leads to impaired RBC production.-Megaloblastic anaemiaIf the maturation of the RBCs in the bone marrow is impaired by lack of Folic acid or Vitamin B12, the cells which enter the blood stream are irregular in size and shape, but usually on average larger than normal. Such anemia is orthochromic and megalocytic. It is usually referred to as Megaloblastic Anemia.
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Cobalamin-Vitamin B12
FunctionsCoenzymes
New Cell Synthesis
Fatty Acids
Amino Acids
Maintain Nerve Cells
Bulk of body stores of vitamin B12 is in the form of coenzyme B12.
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Cobalamin-Vitamin B12
Food Sources
This vitamin has cyanide group and cobalt group. From animal foods like goat liver, fish, eggs & milk.
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Cobalamin-Vitamin B12
Deficiency DiseasePernicious Anemia
Deficiency SymptomsFatigueDegeneration of Peripheral NervesHypersensitivity
Variations in the size and shape of the blood cells.Results in peripheral neuropathy. Loss of mental energy, depression, tingling, numbness, diminished or absent sensation in extrimities.
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Ascorbic Acid-Vitamin C
FunctionsCollagen Synthesis
Antioxidant
Amino Acid Metabolism
Absorption of Iron
Resistance to Infection
Also helps to maintain healthy blood vessels.
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Ascorbic Acid-Vitamin C
Food Sources
Amala, guava, oranges, all citrious fruits, dark green leafy vegetables, tomatoes, etc.
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Ascorbic Acid-Vitamin C
Deficiency DiseaseScurvy
Deficiency Symptoms
--General manifestation of scurvy are fever, rapid pulse, and susceptibility to injection and wound healing is delayed.--Bleeding gums, common cold, delayed wound healing.--Gastrointestinal disturbances, dysuria, skin sensitivity.
Fat Soluble Vitamins
Fat-Soluble Vitamins
Fat Soluble Vitamins: A, D, E, K
*Differ From Water-Soluble Vitamins
Found in Fat and Oily Parts of FoodsInsoluble in WaterLymphatic System
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Fat Soluble Vitamins: A, D, E, K
*Differ From Water-Soluble Vitamins
Greater Risks for ToxicityStored in Liver and Adipose TissueNot Readily Excreted
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Vitamin A and Beta-carotene
First Fat-Soluble Vitamin RecognizedBeta-Carotene, Precursor to Vitamin AThree Forms of Vitamin A (Retinoids)
Retinol (an Alcohol)
Retinal (an Aldehyde)
Retinoic Acid (an Acid)
Circulates in the plasma with the specific retinol binding protein. This combination is called halo-RBP.
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Beta Carotene as an Antioxidant
Protects the Body Against DiseaseFree Radicals
Heart Disease
Cancer
Arthritis
Cataracts
-Encourages immune system to produce the cells you need to fight off infection and promotes rapid recovery.-As anti-oxidant and may aid in reducing the risk of cancer.-Also promotes the growth of healthy bones.
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Retinol-Vitamin A
FunctionsVision
Maintenance of Cornea
Mucous Membranes
Skin, Bone, and Tooth Growth
Food Sources
-It is a vision vitamin.-Keeps skin and mucous membranes smooth and supple.-Promotes the growth of bones and teeth.-Sources- Eggs, liver, fish liver oil, milk and milk products & green leafy vegetables.
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Retinol-Vitamin A in Vision
CorneaTransportation of Light Energy Nerve Impulses at RetinaSupports Growth of Bones
Remodeling of Bone
-It may be affected in severe vitamin A deficiency. It becomes dull and then corneal scar occurs.-Takes part in the formation of bony matrix.
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Retinol-Vitamin A
Deficiency DiseaseHypovitaminosis A
Deficiency Symptoms
Changes in the eyes like night blind ness, xeropthalmia, skin changes ,effects the mucous membrane of the respiratory tract, alimentary tract and genito-urinary tract.Toxicity– Fatigue, loss of appetite, nausea, vomiting, weight loss, irritability, cracking lips, dry skin and hair loss, swelling over long bones.
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Retinol-Vitamin A Deficiency
Vitamin A Stores: 90% in LiverAdequate ProteinVitamin A Food Sources
Global Nutrition ProblemNight Blindness100 Million Children with Deficiency
In liver it is stored in the form of retinyl esters.
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Calciferol-Vitamin D
Significant SourcesFood
Sunlight
Also called Sun shine vitamin. Skin prepares vitamin D in the presence of sunlight.
Calciferol-Vitamin D from the Sun
Natural Exposure to SunlightSun Imposes No Risk of Toxicity
Prolonged Exposure Degrades the Vitamin D Precursor
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Calciferol-Vitamin D from the Sun
Ultraviolet Rays of the SunDark Skinned People Prone to Rickets
Deficiency More Likely in Elderly
Vitamin D Fortified Foods or Supplements
-as it reduces the production of vitamin D.-Osteomalacia is more common in adults. The calcium deficiency results in de-mineralization of bones.-should be taken carefully.
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Calciferol-Vitamin D
FunctionsRaises Blood Calcium and Phosphorus
Hormone
Organs: Intestines, Kidneys, Bones
Stimulates Absorption from GI Tract
Bone Growth
Maintain the blood (plasma) Ca & P levels.Acts like a hormone.Vitamin D main site of action is in the small intestine where promotes Ca & P absorption from the gut & also has direct action on the gut.Raises concentration of plasma Ca & P to promote bone deposition.
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Calciferol-Vitamin D
Deficiency DiseaseRickets
OsteomalaciaDeficiency Symptoms
Deformity of the weight bearing bones, knock knees, bowing of legs.Loss of bone mineral.Pain in bones.
Excessive thirst, diarrhea, nausea, weakness & headach.
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Tocopherol-Vitamin E
1922, Discovery in Vegetable Oils Anti sterility Factor = TocopherolCompound Named Vitamin E
Alpha BetaGamma Delta
Alpha-Tocopherol is the most common and the most active of the seven mentioned forms.
Tocopherol-Vitamin E
Food Sources20% = Vegetable Oils
20% = Fruits and Vegetables
15% = Grain Products
Animal Fats: Meat and Milk Fat Contain Little or No Vitamin E
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Tocopherol-Vitamin E
FunctionsAntioxidant
Stabilization of Cell Membranes
Regulation of Oxidation Reactions
Protection of PUFA
Protection of Vitamin A
-Natural antioxident. It helps to reduce oxidation of lipid membranes, USFA & breakdown of other nutrients by oxygen.-Protect the cell membrane destruction.-It reacts with free radicals & oxidizing agents.-Found in cell membrane that contain PUFA. It inhibits the reaction involving oxygen.-It protects both vitamin A & carotene from oxidation.
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Vitamin E as an Antioxidant
OxidationTransformation of Energy Fuels to ATP
Oxidation of Polyunsaturated Fatty Acids
Protection of Lungs
Air Pollutants (Nitrogen or Ozone)
Protects Red Blood Cells
-prevents the oxidation of USFA-protects lungs from oxidative damage from environmental substances.-protects RBC membrane from oxidative damage.
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Tocopherol-Vitamin E Deficiency
Rare in HumansFat Malapsorption
Cystic FibrosisCauses of Vitamin E Deficiency
Erythrocyte Hemolysis
Deficiency– low fat diet, malabsorption syndrome or after gastric surgery.RBC hemolysis occur more easily in vitamin E deficiency.
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Vitamin K
Blood Clotting
“K” = Danish Word Koagulation (Coagulation or Clotting)
13 Different Proteins and CalciumVitamin K Essential Synthesis of Protein
Calcium andthromboplastin(a phospholipid)
from blood platelets
Vitamin K
PrecursorProthrombin(an inactive
protein)
Thrombin(an activeenzyme)
Fibrinogen(a solubleprotein)
Fibrin(a solid
clot)
Blood-Clotting Process
Originally called Koagulation vitamin.
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Vitamin K
Significant SourcesFood
Non-Food
Bacteria in GI
Bacterial Synthesis
K1 is the naturally occurring form of vitamin K.Bacteria in GI synthesis vitamin K. Normal synthesis is inhibited by the intake of oral antibiotics– K2 vitamin.
Vitamin K
FunctionsBlood-Clotting Synthesis
Bone Growth
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Vitamin K Deficiency
Deficiency is RareBile Production
Diarrhea
Malabsorption Diseases (Crohn’s)
Sulfa Drugs
Antibiotics
Bile production is impaired if there is sever damage to liver as secretion of bile salts is necessary for normal absorption of vitamin K.In steatrrhoea, ulcerative colitis fats are not absorbed effectively, bleeding due to vitamin K deficiency may occur.Sulfa drugs and antibiotics spoils the GI bacterial flora.
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Vitamin K Deficiency
Surgery: Blood Clotting Time CheckedNewborn Babies: Sterile Digestive Tract
Vitamin K-Producing Bacteria
Plasma Prothrombin Concentrations
Hemorrhagic Disease
New born babies has sterile GI tract for about a week & hence a low blood prothrombin level.Due to prolonged antibiotic therapy, prevents the growth of intestinal bacteria.Deficiency of vitamin K produces a lowered prothrombin time.Vitamin K deficiency involves abnormal bleeding as in nose bleeding and internal hemorrhage which can be sever.