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Theme 15
VITAMINS
Vitamin is an organic compound required by the organism as a
nutrient in tiny amounts. In other words, an organic chemical
compound (or related set of compounds) is called vitamin when it
cannot be synthesized in sufficient quantities by an organism, and
must be obtained from the diet. Thirteen vitamins are universally
recognized at present.
The discovery dates of the vitamins and their sources
Year of
discovery
Vitamin Food source
1913 Vitamin А (Retinol) Cod liver oil
1910 Vitamin В1
(Thiamine)
Rice bran
1920 Vitamin С (Ascorbic
acid)
Citrus, most fresh foods
1920 Vitamin D
(Calciferol)
Cod liver oil
1920 Vitamin В2
(Riboflavin)
Meat, eggs
1922 Vitamin Е
(Tocopherol)
Wheat germ oil, unrefined
vegetable oils
1926 Vitamin В12
(Cobalamins)
liver, eggs, animal products
1929 Vitamin К1
(Phylloquinone)
Leafy green vegetables
1931 Vitamin В5
(Pantothenic)
Meat, whole grains, in many
foods
1931 Vitamin В7 (Biotin) Meat, dairy products, eggs
1934 Vitamin В6
(Pyridoxine)
Meat, dairy products
1936 Vitamin В3 (Niacin) Meat, eggs, grains
1941 Vitamin В9 (Folic
acid)
Leafy green vegetables