Vitamins are organic substances which have to be supplied to the food in minute quantities to maintain the biochemical and structural integrity of many cells and tissues in an organism. It cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. Most of them are integral parts of various coenzymes required for biochemical reactions at tissue levels. Vitamins are classified by their biological and chemical activity, not their structure. Thus, each "vitamin" refers to a number of vitamer compounds that all show the biological activity associated with a particular vitamin.
Vitamins have diverse biochemical functions. Some have hormone-like functions and act as regulators of mineral metabolism or regulators of cell and tissue growth and differentiation while others function as antioxidants. The largest number of vitamins function as precursors for enzyme cofactors, that help enzymes in their work as catalysts in metabolism. Alternately, vitamins may also be less tightly bound to enzyme catalysts as coenzymes, detachable molecules which function to carry chemical groups or electrons between molecules.
Vitamins are classified into fat-soluble and water-soluble groups. In humans there are 13 important vitamins the 4 fat-soluble vitamins are vitamins A, D, E and K and the 9 water-soluble vitamins are vitamin C and 8 B-vitamins.
The 4 fat soluble vitamins are:
1) Vitamin A (Retinol)
2) Vitamin D (Calciferol)
3) Vitamin E (Tocopherol)
4) Vitamin K (Phylloquinone)
Water 9 soluble vitamins are:
1) Vitamin C (Ascorbic acid)
2) The 8 B-complex vitamins.
Water-soluble vitamins dissolve easily in water, and in general, are readily excreted from the body, to the degree that urinary output is a strong predictor of vitamin consumption. As the water soluble vitamins are not readily stored, consistent daily intake is important. Many types of water-soluble vitamins are synthesized by bacteria. The B-complex vitamins consists of thiamine, niacin, riboflavin, pyridoxin, biotin, cyanacobalamin, inositol, folic acid, and pantothenic acid. Vitamins are classified by their biological and chemical activity and not their structure. The term vitamin is conditional both on the circumstances and the particular organism, such as the ascorbic acid (vitamin C) is a vitamin for humans and not for most other animals and biotin and vitamin D are required in the human diet only in certain circumstances.
Functions of vitamins include regulators of mineral metabolism e.g. vitamin D, regulators of cell and tissue growth and differentiation e.g. vitamin A, function as antioxidants e.g. vitamin E and vitamin C, function as precursors for enzyme cofactors, that help enzymes in their work as catalysts in metabolism e.g. B complex vitamins.
Vitamin A (Retinol):
It is a fat soluble vitamin.All forms of vitamin A have a beta-ionone ring to which an isoprenoid chain is attached, called a retinyl group. Both structural features are essential for vitamin activity. The orange pigment of carrots - beta-carotene - can be represented as two connected retinyl groups, which are used in the body to contribute to vitamin A levels.
Functions: Vitamin A has a major role in normal visual processes and maintenance of health of epithelial cells. The chemical names are retinol, retinal, and four carotenoids including beta carotene. Vitamin A is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal. This molecule is absolutely necessary for both scotopic and color vision. Vitamin A is necessary for the function of the reproductive systems of both male and female mammals. Vitamin A also functions in a third and very different role, as an irreversibly oxidized form retinoic acid, which is an important hormone-like growth factor for epithelial and other cells.
Dietary requirement: The recommended daily dietary requirement for adult is 900 micrograms. Deficiency of vitamin A is one of the major causes of preventable blindness such as night-blindness and keratomalacia. The overdose of this vitamin is called hypervitaminosis A or hypercarotenemia due to excessive intake of carrots, fish liver etc.
Sources: Vitamin A is exclusively found in animal foods. Rich sources are liver especially fish liver, butter, ghee, cheese, egg yolk, and milk. Vegetable sources contain the precursor of vitamin A carotene. Rich sources of carotene are dark green vegetables such as spinach, amaranth, yellow vegetables like carrot, pumpkin, and fruits like mangoes and papaya.
Vitamin D (Calciferol):
Vitamin D is a group of fat-soluble secosteroids, the two major physiologically relevant forms of which are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol).
Functions: Vitamin D is required for normal metabolism of calcium and phosphorus and for bone formation. It enhances the absorption of calcium and phosphorus from the small intestine, increase mobilization of calcium from bone, and the reabsorption of calcium and phosphorus from the kidneys.
The two major physiologically relevant forms of vitamin D are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D2 is obtained from the diet. Vitamin D3 is produced in the skin of vertebrates after exposure to ultraviolet B light from the sun or artificial sources, and also occurs naturally in some foods. Vitamin D2 (ergocalciferol) obtained by ultraviolet irradiation of ergosterol or ergocalciferol provitamin D2 which is formed by activation of 7-dehydrocholesterol present in the epidermal cells of human skin as a provitamin D2. This activation is affected by the ultraviolet rays ranging in wavelength from 296 A to 310 A obtained from sunlight naturally.
Vitamin D obtained from sun exposure, food, and supplements is biologically inert and must undergo two hydroxylations in the body for activation. Vitamin D is carried in the bloodstream to the liver, where it is converted into the prohormone calcidiol. Circulating calcidiol may then be converted into calcitriol, the biologically active form of vitamin D, either in the kidneys or by monocyte-macrophages in the immune system. When synthesized by monocyte-macrophages, calcitriol acts locally as a cytokine, defending the body against microbial invaders. Vitamin D2 is obtained from the diet and the vitamin D3 is formed endogenously. These two sources complement each other in providing the total supply of vitamin D.
Dietary requirement: The recommended daily dietary requirement for adult is 5.0–10 micrograms. The minimum daily requirement is 400 IU. Deficiency of vitamin D results in impairment of mineralization of bone leading to nutritional rickets in children and osteomalacia in adults. Overdose causes hypervitaminosis D.
Sources: The flesh of fish (such as salmon, tuna, and mackerel) and fish liver oils are among the best sources. Some amount of vitamin D is found in milk, butter, cheese, egg yolk, beef liver, and fish liver oils.
Vitamin E (Tocopherol):
Vitamin E is a generic term for tocopherols and tocotrienols. Vitamin E is a family of alpha, beta, gamma, and delta tocopherols and corresponding four tocotrienols.
Functions: Vitamin E is a strong fat-soluble antioxidant that stops the production of reactive oxygen species formed when fat undergoes oxidation. It prevents the peroxidation of cellular and subcellular membrane phospholipids. It is involved preserving the integrity of cell membranes. It has been claimed that α-tocopherol is the most important lipid-soluble antioxidant, and that it protects cell membranes from oxidation by reacting with lipid radicals produced in the lipid peroxidation chain reaction. This would remove the free radical intermediates and prevent the oxidation reaction from continuing. The oxidised α-tocopheroxyl radicals produced in this process may be recycled back to the active reduced form through reduction by other antioxidants, such as ascorbate, retinol or ubiquinol.
Dietary requirement: The recommended daily dietary requirement for adult is 15.0 mg. Deficiency is very rare; mild hemolytic anemia in newborn infants. Vitamin deficiency leads to infertility. Vitamin E deficiency causes neurological problems due to poor nerve conduction. These include neuromuscular problems such as spinocerebellar ataxia and myopathies. Deficiency can also cause anemia, due to oxidative damage to red blood cells. Overdose causes increased chance of congestive heart failure.
Sources: Particularly high levels of vitamin E can be found in Avocado, eggs, milk, nuts such as almonds, hazelnuts, seeds, spinach and other green leafy vegetables, unheated vegetable oils, wheat germ, wholegrain foods etc.
Vitamin K (Phylloquinone):
Vitamin K1 is also known as phylloquinone or phytomenadione (also called phytonadione). Vitamin K2 (menaquinone, menatetrenone) is normally produced by bacteria in the large intestine.
Functions: Vitamin K denotes a group of lipophilic, hydrophobic vitamins that are needed for the posttranslational modification of certain proteins, mostly required for blood coagulation, but also a number of other proteins that chelate calcium ions and are involved in bone and other tissue metabolism.
Functions: Vitamin K is involved in the carboxylation of certain glutamate residues in proteins to form gamma-carboxyglutamate residues (abbreviated Gla-residues). They play key roles in the regulation of three physiological processes such as blood coagulation, bone metabolism, and vascular biology. Average diets are usually not lacking in vitamin K and primary vitamin K deficiency is rare in healthy adults. Dietary deficiency is extremely rare unless the intestines are heavily damaged, are unable to absorb the molecule, or are subject to decreased production by normal flora, as seen in broad spectrum antibiotic use. Newborn infants are at an increased risk of deficiency. Other populations with an increased prevalence of vitamin K deficiency include individuals who suffer from liver damage or disease (e.g. alcoholics), people with cystic fibrosis, inflammatory bowel diseases or those who have recently had abdominal surgeries. Groups that may suffer from secondary vitamin K deficiency include bulimics, those on stringent diets, and those taking anticoagulants.
Dietary requirement: The recommended daily dietary requirement for adult is 120 microgram. Deficiency disease cause bleeding diathesis. Overdose increases coagulation in patients taking warfarin drug.
Sources: Vitamin K1 is found chiefly in leafy green vegetables such as spinach, cabbage, kale, cauliflower, broccoli, and brussels sprouts, some fruits such as avocado and kiwifruit are also high in vitamin K.
Vitamin C (Ascorbic acid):
Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species, in which it functions as a vitamin.
Functions: In living organisms, ascorbate is an anti-oxidant, since it protects the body against oxidative stress. It is also a cofactor in at least eight enzymatic reactions, including several collagen synthesis reactions that cause the most severe symptoms of scurvy when they are dysfunctional. These reactions are especially important in wound-healing and in preventing bleeding from capillaries. Ascorbate (an ion of ascorbic acid) is required for a range of essential metabolic reactions in all animals and plants. The uses and recommended daily intake of vitamin C range from 45 to 95 mg/day. Proponents of megadosage propose from 200 mg to more than 2000 mg/day. The fraction of vitamin C in the diet that is absorbed and the rate at which the excess is eliminated from the body vary strongly with the dose. The human body can store only a certain amount of vitamin C, and so the body stores are depleted if fresh supplies are not consumed. The time frame for onset of symptoms of scurvy in unstressed adults switched to a completely vitamin C free diet, however, may range from one month to more than six months, depending on previous loading of vitamin C.
Dietary requirement: The recommended daily dietary requirement for adult is 90.0 mg.
Deficiency of vitamin C causes the disease scurvy in humans. In lack of this vitamin, the synthesised collagen is too unstable to perform its function. Scurvy leads to the formation of brown spots on the skin, spongy gums, and bleeding from all mucous membranes. The spots are most abundant on the thighs and legs, and a person with the ailment looks pale, feels depressed, and is partially immobilized. In advanced scurvy there are open, suppurating wounds and loss of teeth and, eventually, death. Over dose of vitamin C is called vitamin C megadosage.
Sources: The richest natural sources are fruits and vegetables and of those, the Kakadu plum, the camu camu fruit, rose hip contain the highest concentration of the vitamin. Fruits such as gooseberry, orange, grape fruit, lemon, passion fruit etc. also contains a high concentration of it. It is also present in some cuts of meat, especially liver.
Vitamin B Complex:
The important B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. The B complex vitamins are:
1. Vitamin B1 (Thiamine)
2. Vitamin B2 (Riboflavin)
3. Vitamin B3 (Niacin or niacinamide)
4. Vitamin B5 (Pantothenic acid)
5. Vitamin B6 (Pyridoxine, pyridoxal, or pyridoxamine)
6. Vitamin B7 (Biotin)
7. Vitamin B9 (folic acid)
8. Vitamin B12 (various cobalamins; commonly cyanocobalamin)
The B vitamins are necessary to support and increase the rate of metabolism, maintain healthy skin and muscle tone, enhance immune and nervous system function, promote cell growth and division, including that of the red blood cells that help prevent anemia, reduce the risk of pancreatic cancer when consumed in food etc.
Vitamin B1(Thiamine)
Deficiency causes beriberi. Symptoms of this disease of the nervous system include weight loss, emotional disturbances, Wernicke's encephalopathy (impaired sensory perception), weakness and pain in the limbs, periods of irregular heartbeat, and edema (swelling of bodily tissues). Heart failure and death may occur in advanced cases.
Dietary requirement: The recommended daily dietary requirement for adult is 1.2 mg. Deficiency causes Beriberi and Wernicke-Korsakoff syndrome. Overdose produce drowsiness or muscle relaxation usually with large doses.
Vitamin B2 (Riboflavin)
Deficiency causes ariboflavinosis. Symptoms may include cheilosis (cracks in the lips), high sensitivity to sunlight, angular cheilitis, glossitis (inflammation of the tongue), seborrheic dermatitis or pseudo-syphilis (particularly affecting the scrotum or labia majora and the mouth), pharyngitis, hyperemia, and edema of the pharyngeal and oral mucosa.
Dietary requirement: The recommended daily dietary requirement for adult is 1.3 mg.
Vitamin B3 (Niacin)
Deficiency, along with a deficiency of tryptophan causes pellagra. Symptoms include aggression, dermatitis, insomnia, weakness, mental confusion, and diarrhea. In advanced cases, pellagra may lead to dementia and death.
Dietary requirement: The recommended daily dietary requirement for adult is 16.0 mg. Overdose causes Liver damage and other problems.
Vitamin B5 (Pantothenic acid)
Deficiency can result in acne and paresthesia.
Dietary requirement: The recommended daily dietary requirement for adult is 5.0 mg. Overdose cause diarrhea, possibly nausea and heartburn.
Vitamin B6 (Pyridoxine)
Deficiency may lead to microcytic anemia, depression, dermatitis, high blood pressure, water retention, and elevated levels of homocysteine.
Dietary requirement: The recommended daily dietary requirement for adult is 1.3–1.7 mg. Higher dose causes impairment of proprioception and nerve damage.
Vitamin B7 (Biotin)
Deficiency does not typically cause symptoms in adults but may lead to impaired growth and neurological disorders in infants. Deficiency causes dermatitis and enteritis. Multiple carboxylase deficiency, an inborn error of metabolism, can lead to biotin deficiency even when dietary biotin intake is normal.
Dietary requirement: The recommended daily dietary requirement for adult is 30.0 microgram.
Vitamin B9 (Folic acid)
Deficiency results in a macrocytic anemia, and elevated levels of homocysteine. Deficiency in pregnant women can lead to birth defects. Supplementation is often recommended during pregnancy.
Dietary requirement: The recommended daily dietary requirement for adult is 400 microgram. Overdose of it may mask symptoms of vitamin B12 deficiency and other effects.
Vitamin B12 (Cobalamin)
Deficiency results in megaloblastic anemia, elevated homocysteine, peripheral neuropathy, memory loss and other cognitive deficits. It is most likely to occur among elderly people, as absorption through the gut declines with age; the autoimmune disease pernicious anemia is another common cause. It can also cause symptoms of mania and psychosis.
Dietary requirement: The recommended daily dietary requirement for adult is 2.4 microgram.
Sources: B vitamins are found in all whole, unprocessed foods. Processed carbohydrates, such as sugar and white flour, tend to have lower B vitamin content than their unprocessed counterparts. B vitamins are particularly concentrated in meat and meat products such as liver, turkey, and tuna. Other good sources for B vitamins are whole grains, potatoes, bananas, lentils, chile peppers, tempeh, beans, nutritional yeast, brewer's yeast, and molasses. The B12 vitamin is of note because it is not available from plant products, making B12 deficiency a concern for vegans.
Hope it helps you in determining the necessary ingredients needed for a balanced diet. Please also do note that it is not advisable to take more than what is needed. Consult a physician for further calculating the dietary value and management of your daily diet style.
Vitamins have diverse biochemical functions. Some have hormone-like functions and act as regulators of mineral metabolism or regulators of cell and tissue growth and differentiation while others function as antioxidants. The largest number of vitamins function as precursors for enzyme cofactors, that help enzymes in their work as catalysts in metabolism. Alternately, vitamins may also be less tightly bound to enzyme catalysts as coenzymes, detachable molecules which function to carry chemical groups or electrons between molecules.
Vitamins are classified into fat-soluble and water-soluble groups. In humans there are 13 important vitamins the 4 fat-soluble vitamins are vitamins A, D, E and K and the 9 water-soluble vitamins are vitamin C and 8 B-vitamins.
The 4 fat soluble vitamins are:
1) Vitamin A (Retinol)
2) Vitamin D (Calciferol)
3) Vitamin E (Tocopherol)
4) Vitamin K (Phylloquinone)
Water 9 soluble vitamins are:
1) Vitamin C (Ascorbic acid)
2) The 8 B-complex vitamins.
Water-soluble vitamins dissolve easily in water, and in general, are readily excreted from the body, to the degree that urinary output is a strong predictor of vitamin consumption. As the water soluble vitamins are not readily stored, consistent daily intake is important. Many types of water-soluble vitamins are synthesized by bacteria. The B-complex vitamins consists of thiamine, niacin, riboflavin, pyridoxin, biotin, cyanacobalamin, inositol, folic acid, and pantothenic acid. Vitamins are classified by their biological and chemical activity and not their structure. The term vitamin is conditional both on the circumstances and the particular organism, such as the ascorbic acid (vitamin C) is a vitamin for humans and not for most other animals and biotin and vitamin D are required in the human diet only in certain circumstances.
Functions of vitamins include regulators of mineral metabolism e.g. vitamin D, regulators of cell and tissue growth and differentiation e.g. vitamin A, function as antioxidants e.g. vitamin E and vitamin C, function as precursors for enzyme cofactors, that help enzymes in their work as catalysts in metabolism e.g. B complex vitamins.
Vitamin A (Retinol):
It is a fat soluble vitamin.All forms of vitamin A have a beta-ionone ring to which an isoprenoid chain is attached, called a retinyl group. Both structural features are essential for vitamin activity. The orange pigment of carrots - beta-carotene - can be represented as two connected retinyl groups, which are used in the body to contribute to vitamin A levels.
Functions: Vitamin A has a major role in normal visual processes and maintenance of health of epithelial cells. The chemical names are retinol, retinal, and four carotenoids including beta carotene. Vitamin A is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal. This molecule is absolutely necessary for both scotopic and color vision. Vitamin A is necessary for the function of the reproductive systems of both male and female mammals. Vitamin A also functions in a third and very different role, as an irreversibly oxidized form retinoic acid, which is an important hormone-like growth factor for epithelial and other cells.
Dietary requirement: The recommended daily dietary requirement for adult is 900 micrograms. Deficiency of vitamin A is one of the major causes of preventable blindness such as night-blindness and keratomalacia. The overdose of this vitamin is called hypervitaminosis A or hypercarotenemia due to excessive intake of carrots, fish liver etc.
Sources: Vitamin A is exclusively found in animal foods. Rich sources are liver especially fish liver, butter, ghee, cheese, egg yolk, and milk. Vegetable sources contain the precursor of vitamin A carotene. Rich sources of carotene are dark green vegetables such as spinach, amaranth, yellow vegetables like carrot, pumpkin, and fruits like mangoes and papaya.
Vitamin D (Calciferol):
Vitamin D is a group of fat-soluble secosteroids, the two major physiologically relevant forms of which are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol).
Functions: Vitamin D is required for normal metabolism of calcium and phosphorus and for bone formation. It enhances the absorption of calcium and phosphorus from the small intestine, increase mobilization of calcium from bone, and the reabsorption of calcium and phosphorus from the kidneys.
The two major physiologically relevant forms of vitamin D are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D2 is obtained from the diet. Vitamin D3 is produced in the skin of vertebrates after exposure to ultraviolet B light from the sun or artificial sources, and also occurs naturally in some foods. Vitamin D2 (ergocalciferol) obtained by ultraviolet irradiation of ergosterol or ergocalciferol provitamin D2 which is formed by activation of 7-dehydrocholesterol present in the epidermal cells of human skin as a provitamin D2. This activation is affected by the ultraviolet rays ranging in wavelength from 296 A to 310 A obtained from sunlight naturally.
Vitamin D obtained from sun exposure, food, and supplements is biologically inert and must undergo two hydroxylations in the body for activation. Vitamin D is carried in the bloodstream to the liver, where it is converted into the prohormone calcidiol. Circulating calcidiol may then be converted into calcitriol, the biologically active form of vitamin D, either in the kidneys or by monocyte-macrophages in the immune system. When synthesized by monocyte-macrophages, calcitriol acts locally as a cytokine, defending the body against microbial invaders. Vitamin D2 is obtained from the diet and the vitamin D3 is formed endogenously. These two sources complement each other in providing the total supply of vitamin D.
Dietary requirement: The recommended daily dietary requirement for adult is 5.0–10 micrograms. The minimum daily requirement is 400 IU. Deficiency of vitamin D results in impairment of mineralization of bone leading to nutritional rickets in children and osteomalacia in adults. Overdose causes hypervitaminosis D.
Sources: The flesh of fish (such as salmon, tuna, and mackerel) and fish liver oils are among the best sources. Some amount of vitamin D is found in milk, butter, cheese, egg yolk, beef liver, and fish liver oils.
Vitamin E (Tocopherol):
Vitamin E is a generic term for tocopherols and tocotrienols. Vitamin E is a family of alpha, beta, gamma, and delta tocopherols and corresponding four tocotrienols.
Functions: Vitamin E is a strong fat-soluble antioxidant that stops the production of reactive oxygen species formed when fat undergoes oxidation. It prevents the peroxidation of cellular and subcellular membrane phospholipids. It is involved preserving the integrity of cell membranes. It has been claimed that α-tocopherol is the most important lipid-soluble antioxidant, and that it protects cell membranes from oxidation by reacting with lipid radicals produced in the lipid peroxidation chain reaction. This would remove the free radical intermediates and prevent the oxidation reaction from continuing. The oxidised α-tocopheroxyl radicals produced in this process may be recycled back to the active reduced form through reduction by other antioxidants, such as ascorbate, retinol or ubiquinol.
Dietary requirement: The recommended daily dietary requirement for adult is 15.0 mg. Deficiency is very rare; mild hemolytic anemia in newborn infants. Vitamin deficiency leads to infertility. Vitamin E deficiency causes neurological problems due to poor nerve conduction. These include neuromuscular problems such as spinocerebellar ataxia and myopathies. Deficiency can also cause anemia, due to oxidative damage to red blood cells. Overdose causes increased chance of congestive heart failure.
Sources: Particularly high levels of vitamin E can be found in Avocado, eggs, milk, nuts such as almonds, hazelnuts, seeds, spinach and other green leafy vegetables, unheated vegetable oils, wheat germ, wholegrain foods etc.
Vitamin K (Phylloquinone):
Vitamin K1 is also known as phylloquinone or phytomenadione (also called phytonadione). Vitamin K2 (menaquinone, menatetrenone) is normally produced by bacteria in the large intestine.
Functions: Vitamin K denotes a group of lipophilic, hydrophobic vitamins that are needed for the posttranslational modification of certain proteins, mostly required for blood coagulation, but also a number of other proteins that chelate calcium ions and are involved in bone and other tissue metabolism.
Functions: Vitamin K is involved in the carboxylation of certain glutamate residues in proteins to form gamma-carboxyglutamate residues (abbreviated Gla-residues). They play key roles in the regulation of three physiological processes such as blood coagulation, bone metabolism, and vascular biology. Average diets are usually not lacking in vitamin K and primary vitamin K deficiency is rare in healthy adults. Dietary deficiency is extremely rare unless the intestines are heavily damaged, are unable to absorb the molecule, or are subject to decreased production by normal flora, as seen in broad spectrum antibiotic use. Newborn infants are at an increased risk of deficiency. Other populations with an increased prevalence of vitamin K deficiency include individuals who suffer from liver damage or disease (e.g. alcoholics), people with cystic fibrosis, inflammatory bowel diseases or those who have recently had abdominal surgeries. Groups that may suffer from secondary vitamin K deficiency include bulimics, those on stringent diets, and those taking anticoagulants.
Dietary requirement: The recommended daily dietary requirement for adult is 120 microgram. Deficiency disease cause bleeding diathesis. Overdose increases coagulation in patients taking warfarin drug.
Sources: Vitamin K1 is found chiefly in leafy green vegetables such as spinach, cabbage, kale, cauliflower, broccoli, and brussels sprouts, some fruits such as avocado and kiwifruit are also high in vitamin K.
Vitamin C (Ascorbic acid):
Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species, in which it functions as a vitamin.
Functions: In living organisms, ascorbate is an anti-oxidant, since it protects the body against oxidative stress. It is also a cofactor in at least eight enzymatic reactions, including several collagen synthesis reactions that cause the most severe symptoms of scurvy when they are dysfunctional. These reactions are especially important in wound-healing and in preventing bleeding from capillaries. Ascorbate (an ion of ascorbic acid) is required for a range of essential metabolic reactions in all animals and plants. The uses and recommended daily intake of vitamin C range from 45 to 95 mg/day. Proponents of megadosage propose from 200 mg to more than 2000 mg/day. The fraction of vitamin C in the diet that is absorbed and the rate at which the excess is eliminated from the body vary strongly with the dose. The human body can store only a certain amount of vitamin C, and so the body stores are depleted if fresh supplies are not consumed. The time frame for onset of symptoms of scurvy in unstressed adults switched to a completely vitamin C free diet, however, may range from one month to more than six months, depending on previous loading of vitamin C.
Dietary requirement: The recommended daily dietary requirement for adult is 90.0 mg.
Deficiency of vitamin C causes the disease scurvy in humans. In lack of this vitamin, the synthesised collagen is too unstable to perform its function. Scurvy leads to the formation of brown spots on the skin, spongy gums, and bleeding from all mucous membranes. The spots are most abundant on the thighs and legs, and a person with the ailment looks pale, feels depressed, and is partially immobilized. In advanced scurvy there are open, suppurating wounds and loss of teeth and, eventually, death. Over dose of vitamin C is called vitamin C megadosage.
Sources: The richest natural sources are fruits and vegetables and of those, the Kakadu plum, the camu camu fruit, rose hip contain the highest concentration of the vitamin. Fruits such as gooseberry, orange, grape fruit, lemon, passion fruit etc. also contains a high concentration of it. It is also present in some cuts of meat, especially liver.
Vitamin B Complex:
The important B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. The B complex vitamins are:
1. Vitamin B1 (Thiamine)
2. Vitamin B2 (Riboflavin)
3. Vitamin B3 (Niacin or niacinamide)
4. Vitamin B5 (Pantothenic acid)
5. Vitamin B6 (Pyridoxine, pyridoxal, or pyridoxamine)
6. Vitamin B7 (Biotin)
7. Vitamin B9 (folic acid)
8. Vitamin B12 (various cobalamins; commonly cyanocobalamin)
The B vitamins are necessary to support and increase the rate of metabolism, maintain healthy skin and muscle tone, enhance immune and nervous system function, promote cell growth and division, including that of the red blood cells that help prevent anemia, reduce the risk of pancreatic cancer when consumed in food etc.
Vitamin B1(Thiamine)
Deficiency causes beriberi. Symptoms of this disease of the nervous system include weight loss, emotional disturbances, Wernicke's encephalopathy (impaired sensory perception), weakness and pain in the limbs, periods of irregular heartbeat, and edema (swelling of bodily tissues). Heart failure and death may occur in advanced cases.
Dietary requirement: The recommended daily dietary requirement for adult is 1.2 mg. Deficiency causes Beriberi and Wernicke-Korsakoff syndrome. Overdose produce drowsiness or muscle relaxation usually with large doses.
Vitamin B2 (Riboflavin)
Deficiency causes ariboflavinosis. Symptoms may include cheilosis (cracks in the lips), high sensitivity to sunlight, angular cheilitis, glossitis (inflammation of the tongue), seborrheic dermatitis or pseudo-syphilis (particularly affecting the scrotum or labia majora and the mouth), pharyngitis, hyperemia, and edema of the pharyngeal and oral mucosa.
Dietary requirement: The recommended daily dietary requirement for adult is 1.3 mg.
Vitamin B3 (Niacin)
Deficiency, along with a deficiency of tryptophan causes pellagra. Symptoms include aggression, dermatitis, insomnia, weakness, mental confusion, and diarrhea. In advanced cases, pellagra may lead to dementia and death.
Dietary requirement: The recommended daily dietary requirement for adult is 16.0 mg. Overdose causes Liver damage and other problems.
Vitamin B5 (Pantothenic acid)
Deficiency can result in acne and paresthesia.
Dietary requirement: The recommended daily dietary requirement for adult is 5.0 mg. Overdose cause diarrhea, possibly nausea and heartburn.
Vitamin B6 (Pyridoxine)
Deficiency may lead to microcytic anemia, depression, dermatitis, high blood pressure, water retention, and elevated levels of homocysteine.
Dietary requirement: The recommended daily dietary requirement for adult is 1.3–1.7 mg. Higher dose causes impairment of proprioception and nerve damage.
Vitamin B7 (Biotin)
Deficiency does not typically cause symptoms in adults but may lead to impaired growth and neurological disorders in infants. Deficiency causes dermatitis and enteritis. Multiple carboxylase deficiency, an inborn error of metabolism, can lead to biotin deficiency even when dietary biotin intake is normal.
Dietary requirement: The recommended daily dietary requirement for adult is 30.0 microgram.
Vitamin B9 (Folic acid)
Deficiency results in a macrocytic anemia, and elevated levels of homocysteine. Deficiency in pregnant women can lead to birth defects. Supplementation is often recommended during pregnancy.
Dietary requirement: The recommended daily dietary requirement for adult is 400 microgram. Overdose of it may mask symptoms of vitamin B12 deficiency and other effects.
Vitamin B12 (Cobalamin)
Deficiency results in megaloblastic anemia, elevated homocysteine, peripheral neuropathy, memory loss and other cognitive deficits. It is most likely to occur among elderly people, as absorption through the gut declines with age; the autoimmune disease pernicious anemia is another common cause. It can also cause symptoms of mania and psychosis.
Dietary requirement: The recommended daily dietary requirement for adult is 2.4 microgram.
Sources: B vitamins are found in all whole, unprocessed foods. Processed carbohydrates, such as sugar and white flour, tend to have lower B vitamin content than their unprocessed counterparts. B vitamins are particularly concentrated in meat and meat products such as liver, turkey, and tuna. Other good sources for B vitamins are whole grains, potatoes, bananas, lentils, chile peppers, tempeh, beans, nutritional yeast, brewer's yeast, and molasses. The B12 vitamin is of note because it is not available from plant products, making B12 deficiency a concern for vegans.
Hope it helps you in determining the necessary ingredients needed for a balanced diet. Please also do note that it is not advisable to take more than what is needed. Consult a physician for further calculating the dietary value and management of your daily diet style.
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