What are vitamins?
A vitamin is one of a group of organic substances, present in minute amounts in natural foodstuffs, that are essential to normal metabolism;insufficient amounts in the diet may cause deficiency diseases.
Vitamins are divided into two groups: (i) Fat-soluble Vitamins – Vitamins A, D, E and K are fat-soluble (ii) Water-soluble Vitamins – Vitamins C and all the B vitamins are water-soluble.
Vitamin A (Chemical Name: Retinol)
Vitamin A plays an important role in bone growth, tooth development, reproduction, cell division, gene expression, and regulation of the immune system. The skin, eyes, and mucous membranes of the mouth, nose, throat and lungs depend on vitamin A to remain moist. Vitamin A is also an important antioxidant that may play a role in the prevention of certain cancers.
Source: liver, cod liver oil, carrot, broccoli, sweet potato, butter, kale, spinach, pumpkin, collard greens, some cheeses, egg, apricot, cantaloupe melon, milk.
Deficiency Disease: Night blindness and keratomalacia (eye disorder that results in a dry cornea)
Vitamin B1 (Chemical Name: Thiamine)
Source: Sources include peas, pork, liver, and legumes. Most commonly, thiamin is found in whole grains and fortified grain products such as cereal, and enriched products like bread, pasta, rice, and tortillas.
Deficiency Disease: Beri-Beri, Wernicke-Korsakoffsyndrome
Vitamin B2 (Chemical Name: Riboflavin)
Source: Sources include liver, eggs, dark green vegetables, legumes, whole and enriched grain products, and milk. Ultraviolet light is known to destroy riboflavin, which is why most milk is packaged in opaque containers instead of clear.
Deficiency Disease: Cheilosis, ariboflavinosis
Vitamin B3 (Chemical Name: Niacin)
Source: Sources include liver, fish, poultry, meat, peanuts, whole and enriched grain products.
Deficiency Disease: Pellagra
Vitamin B5 (Chemical Name: Pantothenic Acid)
Source: meats, whole grains (milling may remove it), broccoli, avocados, royal jelly, fish ovaries.
Deficiency Disease: Paresthesia
Vitamin B6 (Chemical Name: Pyridoxine)
Source: meats, bananas, whole grains, vegetables, and nuts. When milk is dried it loses about half of its B6. Freezing and canning can also reduce content.
Deficiency Disease: anemia, peripheral neuropathy
Vitamin B7 (Chemical Name: Biotin)
Source: egg yolk, liver, some vegetables
Deficiency Disease: dermatitis, enteritis
Vitamin B9 (Chemical Name: Folic Acid)
Source: Sources of folate include liver, kidney, dark green leafy vegetables, meats, fish, whole grains, fortified grains and cereals, legumes, and citrus fruits. Not all whole grain products are fortified with folate.
Deficiency Disease: pregnancy deficiency linked to birth defects
Vitamin B12 (Chemical Name: Cynacobalamin)
Vitamin B12, also known as cobalamin, aids in the building of genetic material, production of normal red blood cells, and maintenance of the nervous system.
Source: Vitamin B12 can only be found only in foods of animal origin such as meats, liver, kidney, fish, eggs, milk and milk products, oysters, shellfish. Some fortified foods may contain vitamin B12.
Deficiency Disease: megaloblastic anemia
Vitamin C (Chemical Name: Ascorbic Acid)
Vitamin C benefits the body by holding cells together through collagen synthesis;collagen is a connective tissue that holds muscles, bones, and other tissues together. Vitamin C also aids in wound healing, bone and tooth formation, strengthening blood vessel walls, improving immune system function, increasing absorption and utilization of iron, and acting as an antioxidant
Source: Consuming vitamin C-rich foods is the best method to ensure an adequate intake of this vitamin. While many common plant foods contain vitamin C, the best sources are citrus fruits.
Deficiency Disease: Scurvy, causing a loss of collagen strength throughout the body. Loss of collagen results in loose teeth, bleeding and swollen gums, and improper wound healing.
Vitamin D (Chemical Name: Calciferol)
Vitamin D plays a critical role in the body’s use of calcium and phosphorous. It works by increasing the amount of calcium absorbed from the small intestine, helping to form and maintain bones. Vitamin D benefits the body by playing a role in immunity and controlling cell growth. Children especially need adequate amounts of vitamin D to develop strong bones and healthy teeth.
Source: produced in the skin after exposure to ultraviolet B light from the sun or artificial sources. Also found in fatty fish, eggs, beef liver, and mushrooms.
Deficiency Disease: Rickets
Vitamin E (Chemical Name: Tocopherol)
Vitamin E benefits the body by acting as an antioxidant, and protecting vitamins A and C, red blood cells, and essential fatty acids from destruction. Research from decades ago suggested that taking antioxidant supplements, vitamin E in particular, might help prevent heart disease and cancer.
Source: kiwi fruit, almonds, avocado, eggs, milk, nuts, leafy green vegetables, unheated vegetable oils, wheat germ, and wholegrains.
Deficiency Disease: May cause mild hemolytic anemia in newborns.
Vitamin K (Chemical Name: Phylloquinone)
Vitamin K is naturally produced by the bacteria in the intestines, and plays an essential role in normal blood clotting, promoting bone health, and helping to produce proteins for blood, bones, and kidneys.
Source: leafy green vegetables, avocado, kiwi fruit. Parsley contain a lot of vitamin K.
Deficiency Disease: Haemophilia