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4.6.2. Water soluble vitamins

Water soluble vitamins

They are soluble in water, and therefore they diffuse very well through the blood. They are coenzymes or precursors of coenzymes, necessary for many chemical reactions of metabolism. The excess of ingested vitamins does not cause disorders, since it is excreted in the urine, which is why an almost daily intake is required, because as it is not stored, it depends on the diet. This group includes the B complex vitamins (vitamins B1, B2, B3, B5, B6, B8, B9 and B12) and vitamin C.

    Vitamin B complex

    This complex contains a large number of vitamins: vitamin B1 or thiamine, vitamin B2 or riboflavin, vitamin B3, PP or niacin, vitamin B5 or pantothenic acid, vitamin B6 or pyridoxine, vitamin B8 or biotin, vitamin B9 or folic acid, and vitamin B12 or cobalamin.

    Vitamin B1 or thiamine

    • Sources. It is produced by many bacteria, fungi (yeasts) and vegetables and appears abundantly in the casings of cereals and legumes. Also in pigs and offal.
    • Action. Regulates carbohydrate metabolism. The diphosphotiamine form transforms pyruvic acid into the acetyl group, a necessary step in the Krebs cycle.
    • Deficit. Its deficiency produces a picture of symptoms called beriberi, which is characterized by a degeneration of neurons (neuritis) and is manifested by muscle weakness, lack of coordination, hypersensitivity, heart failure, lack of appetite, edema and, in extreme cases, the death.

    Vitamina B1 o tiamina

    By NEUROtiker (Own work) [Public domain], via Wikimedia Commons

    Vitamin B2 o riboflavin

    • Sources. It appears in almost all foods. It is produced by bacteria, yeasts and yellow vegetables (with pigments such as yellow anthoxanthin). It is also found in milk, eggs, liver ...
    • Action. It is part of the FAD (flavin-adenindinucleotide) and the FMN (flavin-mononucleotide). Both are coenzymes of dehydrogenase enzymes that act in cellular respiratory processes, especially in the oxidation of carbohydrates and amino acids.
    • Deficit. Its lack causes alterations such as redness and irritability of the lips, tongue, cheeks and eyes; These, in addition, accuse discomfort when faced with light (photophobia).

    De No machine-readable author provided. Kaprak assumed (based on copyright claims). - No machine-readable source provided. Own work assumed (based on copyright claims)., Dominio público, Ligazón

    Vitamin B3, Niacin, Vitamin PP or Nicotinic Acid

    This vitamin is also known by the names of nicotinic acid or vitamin PP (pellagra preventive). A variant is nicotinamide.

    • Sources. It is produced by fungi, so it is abundant in foods obtained by fermentation with yeast. Animals can synthesize it from tryptophan. It is also abundant in milk and meat.
    • Action. It is part of NAD (nicotin-adenine-dinucleotide) and NADP (NAD phosphate), which are coenzymes of enzymes responsible for dehydrogenation in the oxidation processes of carbohydrates and protides.
    • Deficit. Its deficiency causes the appearance of pellagra, which is characterized by redness of the oral cavity, digestive system disorders (with vomiting, diarrhea and nausea), the appearance of rough and dark-colored skin in areas exposed to the action of the sun. In severe cases, nervous and mental disorders occur (confusion, memory loss, depression, hallucinations, persecutory manias ...) and, in extreme cases, death.
    • Excess. It is the only water-soluble vitamin that causes disorders when ingested in large quantities. These disorders are: redness, burning and itching of the skin.

    By User:Mysid (Self-made in bkchem; edited in vim.) [Public domain], via Wikimedia Commons

    Vitamin B5 or Pantothenic Acid Vitamin B5

    • Sources. It is synthesized by bacteria, fungi (yeasts) and green leafy vegetables. It appears in all animal tissues, where it is stored.
    • Action. It is part of coenzyme A, which is involved in the formation and degradation of fatty acids and cholesterol. Its activity in a large number of metabolic reactions is also known.
    • Deficit. Its deficiency produces dermatitis, depigmentation, anemia and growth retardation.

    By Jü (Own work) [CC0], via Wikimedia Commons

    Vitamin B6 or pyridoxine

    • Sources. It is synthesized by green leafy vegetables and yeasts. Animals accumulate it in the liver, so this organ is rich in this vitamin.
    • Action. They act in the formation of niacin from tryptophan. Therefore, its deficiency symptoms are confused with that of this vitamin. Furthermore, pyridoxine phosphate is a coenzyme of enzymes that regulate amino acid metabolism.
    • Deficit. Its deficiency causes anemia, accompanied by sleep disturbances, irritability and possible mental disorders.

    Mysid [Public domain], via Wikimedia Commons

    Vitamin B8 or biotin or vitamin H

    • Sources. It is produced by plants and bacteria. Animals obtain biotin by absorption through the intestinal wall, where it is also produced by the bacterial flora.
    • Action. It acts in CO2 fixation reactions (carboxylations).
    • Deficit. Its deficiency causes paleness, dermatitis, muscle aches and anemia.

    By User:Mysid [Public domain], via Wikimedia Commons

    Vitamin B9 or folic acid

    • Sources. It appears in a large number of foods: liver, kidney, foods produced by fermentation with yeast, eggs, milk, seeds, green vegetables.
    • Action. It is a coenzyme that, in conjunction with an apoenzyme, is responsible for the transfer of monocarbon groups. Its activity in the formation of purines and pyrimidines has been proven. Its relationship with growth processes and erythropoiesis (formation of red blood cells) is also known.
    • Deficit. Its deficiency in adults causes anemia and, in children, growth arrest. Its deficiency during pregnancy produces congenital malformations.

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    Vitamin B12 or cyanocobalamin

    It is called cobalamin, as it has a porphyrin ring associated with a cobalt atom. Several derivatives of vitamin B12 are known to be active: vitamin B12a or cyanocobalamin, vitamin B12b or hydroxycobalamin , vitamin B12c, or nitrocobalamin and j-cobalamin.

    • Sources. It is produced by bacteria. Animals obtain it at the level of the intestinal wall, since it is produced by intestinal bacteria. In red meat, eggs and dairy products.
    • Action. It is involved in the metabolism of protein and nucleic acid formation. It also acts in erythropoiesis.
    • Deficit. The lack of this vitamin causes a serious type of anemia called pernicious, due to malformations of the red blood cells.

    By Ymwang42 (talk). Original uploader was Ymwang42 at en.wikipedia - Transferred from en.wikipedia (Original text : I created this work entirely by myself.), Public Domain, Link

    Vitamin C or ascorbic acid

    • Sources. Vegetables synthesize it, as do a large number of animals. Vitamin C is abundant in citrus fruits, vegetables, and cow's milk.
    • Action. It is a powerful reducer through its oxidation in dehydroascorbic acid. Its activity in the synthesis of collagen, a fiber that is part of reticular tissues, responsible for maintaining tissue cohesion, has been proven.
    • Deficit. The lack of vitamin C causes a picture of symptoms called scurvy, characterized by bleeding, bleeding gums, tooth loss and digestive disorders. All this favors the appearance of infections and, in severe cases, even death.


    By Yikrazuul (Own work) [Public domain], via Wikimedia Commons


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