Vitamin B

The B vitamins or vitamin B complex are a group of eight, chemically distinct, water-soluble vitamins that were once considered a single vitamin (like Vitamin C or Vitamin D), but now are seen as a complex of vitamins that have loosely similar properties and generally are found in the same foods. Vitamins are organic (carbon-containing) nutrients obtained through the diet and essential in small amounts for normal metabolic reactions. The B vitamins play important roles in cell metabolism.

The B vitamins include thiamine, riboflaven, niacin, pantothenic acid, pyridoxine, biotin, folic acid, and cobalamin. These are also referred to by a number, such as Vitamin B₁ for thiamine and Vitamin B₂ for riboflavin. In contradistinction to the defintion given above for vitamin, some authorities include choline, inositol, PABA (para-aminobenzoic acid), and lipoic acid as part of the B vitamins (Longe 2005). However, these four unnumbered nutrients are not essential because they can be synthesized by the body.

List of B vitamins

• Vitamin B₁ (Thiamine)
• Vitamin B₂ (Riboflavin)
• Vitamin B₃, also Vitamin P or Vitamin PP (Niacin)
• Vitamin B₅ (Pantothenic acid)
• Vitamin B₆ (Pyridoxine and Pyridoxamine)
• Vitamin B₇, also Vitamin H (Biotin)
• Vitamin B₉, also Vitamin M and Vitamin B-c (Folic acid)
• Vitamin B₁₂ (Cobalamin)

The numbers that do not appear in the sequence, Vitamin B₄, Vitamin B₈, and so forth, were nutrients that were either found to be duplicate substances or non-vitamins (see related nutrients).

Health benefits

The B vitamins often work together to deliver a number of health benefits to the body. B vitamins have been shown to:

• Bolster 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.

Together, they also help combat the symptoms and causes of stress, depression, and cardiovascular disease.

All B vitamins are water soluble, and are dispersed throughout the body. They must be replenished daily with any excess excreted in the urine.

Vitamin B sources

B vitamins come from a number of natural sources, including potatoes, bananas, lentils, chilli peppers, tempeh, liver, turkey, and tuna. Nutritional yeast (or brewer's yeast) is an especially good source. The Australian spread Vegemite bills is considered a rich source of the B vitamins. As might be expected, due to its high content of brewer's yeast, beer is a good source of B vitamins (Glaser 2002), although this may not be true of filtered beers (Harden and Zylva 1924).

Another popular means of increasing one's intake of the B vitamins is through the use of dietary supplements. B vitamins are also commonly added to energy drinks.

B vitamins deficiency

Several named vitamin deficiency diseases may result from the lack of sufficient B vitamins.

• 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. Chronic thiamine deficiency can also cause Korsakoff's syndrome, an irreversible psychosis characterized by amnesia and confabulation.
• 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.
• 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.

Deficiencies of other B vitamins result in symptoms that are not part of a named deficiency disease.

• Vitamin B₅ (Pantothenic acid) deficiency can result in acne and Paresthesia, although it is uncommon.
• Vitamin B₆ (Pyridoxine) deficiency may lead to anemia, depression, dermatitis, high blood pressure (hypertension), water retention, and elevated levels of homocysteine.
• Vitamin B₇ deficiency does not typically cause symptoms in adults but may lead to impaired growth and neurological disorders in infants.
• Vitamin B₉ (Folic acid) deficiency results in elevated levels of homocysteine. Deficiency in pregnant women can lead to birth defects. Supplementation is often recommended during pregnancy. Researchers have shown that folic acid might also slow the insidious effects of age on the brain.
• Vitamin B₁₂ (Cobalamin) deficiency causes pernicious anemia, memory loss, and other cognitive decline. It is most likely to occur among elderly people as absorption through the gut declines with age. In extreme (fortunately rare) cases, paralysis can result.

Related nutrients

Many of the following substances have been referred to as vitamins because they were believed to be vitamins at one time. They are relevant to vitamin nomenclature in that the numbers that were assigned to them form "gaps" in the series of B-vitamin names. While they are non-"essential" to humans in that they may be synthesized by the body from other starting materials, they have dietary significance. Some of them, though not essential to humans, are essential to other organisms.

• Vitamin B₄: Adenine, a nucleobase.
• Vitamin B₇: "Vitamin I" of Centanni E. (1935) — also called 'Enteral factor' is a water and alcohol soluble rice-bran factor which prevents digestive disturbance in pigeons. It governs the anatomical and functional integrity of the intestinal tract. Later found in yeast. Possible candidates for this substance are inositol, nicotinic acid(niacin), and biotin. Carnitine was also claimed to be a candidate but is not soluble in alcohol.^{[citation needed]}
• Vitamin B₈: adenosine monophosphate
• Vitamin B₁₀: para-aminobenzoic acid, or PABA
• Vitamin B₁₁: Pteryl-hepta-glutamic acid – Chick growth factor, which is a form of Folic acid. Later found to be one of five folates necessary for humans; (L-carnitine) is called Vitamin B₁₁ in France^{[citation needed]}.
• Vitamin B₁₃: Orotic acid.
• Vitamin B₁₄: cell proliferant, anti-anemia, rat growth, and antitumor pterin phosphate named by Earl R. Norris (biochemist of folic acid fame). Isolated from human urine at 0.33ppm (later in blood), but later abandoned by him as further evidence did not comfirm this. He also claimed this was not Xanthopterin.
• Vitamin B₁₅ 6-O-(dimethylaminoacetyl)-D-gluconic acid (Pangamic acid)
• Vitamin B₁₆ (dimethylgycine) – also known as DMG. (However Lipoic acid was discovered and named a B-Vitamin after B15 and before B17)
• Vitamin B₁₇ (Amygdalin) – proponents claim this is effective in cancer treatment and prevention and is commonly found in apricot kernels.
• Vitamin B₁₈ –
• Vitamin B₁₉ –
• Vitamin B₂₀ (Carnitine) –
• Vitamin B₂₁ –
• Vitamin B₂₂ – often claimed as an ingredient of Aloe vera extracts but also in many other foods. Claimed by one source to be Vitamin B12b-δ.
• Vitamin B_h – another name for Biotin
• Vitamin B_m ("mouse factor") – also used to designate Inositol
• Vitamin B_p (Choline) –
• Vitamin B_t (L-carnitine) –
• Vitamin B_v – a type of B6 but not Pyrodoxine
• Vitamin B_w – a type of Biotin but not d-Biotin
• Vitamin B_x – another name for PABA (para-Aminobenzoic acid)
• Lipoic acid –

Note: B₁₆, B₁₇, B₁₈, B₁₉, B₂₀, B₂₁ & B₂₂ do not appear to be animal factors but are claimed by naturopaths as human therapedic factors.

References

ISBN links support NWE through referral fees

,

.

Clark, Linda A. 1981. Know your nutrition. New Canaan, Conn: Keats Pub. ISBN 0879834013.

Longe, Jacqueline L. (Ed.) 2005. The Gale encyclopedia of alternative medicine. Detroit: Thomson/Gale. ISBN 0787693960.

External links

• How B Vitamins Work

Credits

New World Encyclopedia writers and editors rewrote and completed the Wikipedia article in accordance with New World Encyclopedia standards. This article abides by terms of the Creative Commons CC-by-sa 3.0 License (CC-by-sa), which may be used and disseminated with proper attribution. Credit is due under the terms of this license that can reference both the New World Encyclopedia contributors and the selfless volunteer contributors of the Wikimedia Foundation. To cite this article click here for a list of acceptable citing formats.The history of earlier contributions by wikipedians is accessible to researchers here:

• B_vitamins  ^history

The history of this article since it was imported to New World Encyclopedia:

• History of "Vitamin B"

Note: Some restrictions may apply to use of individual images which are separately licensed.