Reviewed By: Pramod Kerkar, MD, FFARCSI

What are Vitamins?

Vitamins are a group of inorganic compounds naturally occurring in food, needed in very small quantities by our bodies, to perform various important functions like immunity, energy production, and making red blood cells. Our body cannot synthesize vitamins; hence, we need to attain them through food. Maintaining a balanced diet fulfils the body’s need of vitamins.

What Are The Different Types Of Vitamin B?

About Vitamin B

Vitamin B group (or B-complex) is a collection of 8 water-soluble vitamins, sharing general similarities, but each performing a critical biochemical processes in the body. They include vitamins B1, B2, B3, B5, B6, B7, B9 and B12. They may all work in coordination in aiding metabolism and assisting chemical reaction in the body, but they exist independently and have each has a distinct chemical composition. B vitamins are structural components of cells and are coenzymes in chemical reactions that take place inside a cell. The body uses carbohydrates, fat and protein for fuel. The vitamin B group help the body use that fuel.

The human body does not naturally produce Vitamin B and they are easily used, destroyed or quickly eliminated from the body. Food processing too reduces the amount of B-group vitamins in foods. With the exception of vitamin B12, which can be recycled and reused by the body, the body has a limited capacity to store and reuse B group vitamins. As most of the B vitamins are found in the same foods, a proper nutritious diet can fulfil the body’s requirement for this nutrient. A person who has a poor diet may end up with B-group vitamins deficiency. B vitamins work in complex interdependence and a deficiency in one may lead to the improper functioning of the others. It is important to not self-diagnose a vitamin deficiency and consult a doctor before taking vitamin supplements as overdosing can be toxic.

Types of Vitamin B & Their Discovery, Sources, Role, Deficiency

Following is a list of each type of the Vitamin B family and the essential role each plays in the proper functioning of the body:

Vitamin B1: Discovery, Sources, Role & Deficiency

Also known as Thiamine, vitamin B1 acts as a coenzyme in the catabolism of amino acids and sugar.

Discovery of Vitamin B1: Vitamin B1 It was discovered in the 1890s by a Dutch military physician by the name of Christiaan Eijkman who while finding a cure for beriberi disease, discovered that the disease was linked to consumption of white rice, and by adding back the rice bran the symptoms could be reversed. Those polishing contained Thiamine. Eijkman received the 1929 Nobel Prize in Physiology or Medicine for his recognition of this “anti-beriberi factor”.

Role of Vitamin B1: Vitamin B1 supports normal nervous system functioning, conversion of glucose into energy, production of hydrochloric acid necessary for chemical digestion of food and is involved in RNA and DNA production.

Sources of Vitamin B1: Thiamine or vitamin B1 is found in a wide variety of foods, some of its best sources being wholemeal cereal grains, sesame seeds, legumes, wheat germ, peas, milk, cauliflower, spinach, nuts, squash, red meat such as pork and liver, eggs and yeast.

Vitamin B1 Deficiency: Deficiency of vitamin B1 is common in Asian countries where white rice is the staple diet. In western countries, this deficiency is caused due to poor diet and alcoholism. A number of diseases are caused due to vitamin B1 deficiency such as beriberi that affects the cardiovascular, muscular, and gastrointestinal and nervous systems. A person suffering from ‘dry’ beriberi may have nerve degeneration, poor arm and leg coordination, weight loss, emotional disturbances. Korsakoff syndrome is an irreversible dementia linked to alcohol excess and a thiamine-deficient diet. Its symptoms include involuntary movement of the eyeball, amnesia and mental confusion. Heart failure and death can be caused in the advanced stages.

Vitamin B2: Discovery, Sources, Role & Deficiency

This type of vitamin B is also known as Riboflavin and is a precursor of two enzymatic cofactors called FAD and FMN, required for flavoprotein enzymatic reactions.

Discovery of Vitamin B2: Vitamin B2 is the second B vitamin to be discovered and D.T. Smith and E.G. Hendrick discovered riboflavin in 1926.

Role of Vitamin B2: Riboflavin or Vitamin B2 is primarily involved in cellular energy production in the citric acid cycle, electron transport chain and beta-oxidation (catabolism of fatty acids). It is involved in breaking down of proteins and fats, production of red blood cells, assists in maintaining skin and eye health and cell development and growth.

Sources of Vitamin B2: Riboflavin is found in a wide variety of foods, some of its best sources being milk, yoghurt, cottage cheese, eggs, salmon, beef, spinach, organ meat, egg whites, and leafy greens.

Vitamin B2 Deficiency: Vitamin B2 deficiency is rare and affects alcohol addicts and those who do not consume milk products. A number of diseases are caused due to vitamin B1 deficiency, such as ariboflavinosis, symptoms include cracked lips, swelling of tongue, tongue turning purple red, anxiety, high sensitivity to sunlight, sore throat, pseudo-syphilis affecting mainly the scrotum and mouth, hair loss and skin rash.

Vitamin B3: Discovery, Sources, Role & Deficiency

This type of vitamin B is also known as Niacin and is a precursor or nicotinic acid and nicotinamide. Both of the B vitamins are essential in oxidative phosphorylation, energy transfer reactions in the metabolism of glucose, fat and alcohol.

Discovery of Vitamin B3: Conrad Arnold Elvehjem discovered the chemical structure of Vitamin B3 in 1937.

Role of Vitamin B3: Niacin or Vitamin B3 is essential for cellular energy production. The nicotinic acid carries hydrogen and their electrons during metabolic reactions, nicotinamide acid as a coenzyme in lipid and nucleic acid synthesis. Vitamin B3 helps convert carbohydrates, fat and alcohol to energy. Vitamin B3 is essential in maintaining the health of the skin, digestive and nervous systems and creating new cells. The body can produce vitamin B3, but in small quantities.

Sources of Vitamin B3: Vitamin B3 or niacin is found in a wide variety of foods, some of its best sources being wholegrain breads and cereals, nuts, lentils, mushrooms meat, poultry, fish and beef.

Vitamin B3 Deficiency: People suffering from vitamin B3 deficiency are usually alcoholics, those with digestive problems in which case niacin is not absorbed properly. Symptoms of pellagra include dermatitis, diarrhoea, dementia, insomnia, mental confusion, loss of appetite, dizziness, weakness and aggression.

Vitamin B5: Discovery, Sources, Role & Deficiency

This type of Vitamin B is also known as Pantothenic acid and is a precursor of the coenzyme-A. Synthesised from pantothenic acid, Coenzyme A, is involved in the synthesis of amino acids, fatty acids, neurotransmitters and antibodies.

Discovery of Vitamin B5: Vitamin B5 was discovered in 1933 by physician R.J.William while researching for the essential nutrients for yeast.

Role of Vitamin B5: Vitamin B5 is essential for cell energy production in the body. Vitamin B5 is required to metabolise carbohydrates, proteins, fats, alcohol, and production of steroid hormones, lipids neurotransmitters and red blood cells. Vitamin B5 can be made by the body, but in small quantities.

Sources of Vitamin B5: Vitamin B5 or pantothenic acid is widely available in plant and animal food sources and is found in a wide variety of foods, some of its best sources being whole grains, avocados, cashew nuts, peanuts, lentils, soybeans, meat, poultry, fish, organ meats (liver, kidney), broccoli and milk.

Vitamin B5 Deficiency: Vitamin B5 deficiency is extremely rare and its symptoms include loss of appetite, insomnia, fatigue, constipation, vomiting, intestinal distress, acne and paresthesias.

Vitamin B6: Discovery, Sources, Role & Deficiency

Vitamin B6 is also known as pyridoxine and this vitamin B type functions as a coenzyme in the metabolism of amino acids, glucose, and lipids. Pyridoxine is the most common form of Vitamin B supplements.

Discovery of Vitamin B6: In 1934, Paul Gyorgy discovered vitamin B6.

Role of Vitamin B6: Pyridoxine or Vitamin B6 is essential in maintaining the various bodily functions. Involved in over 100 cellular reactions throughout the body, vitamin B6 is needed to metabolize amino acids and glycogen, is involved in making vitamin B3, amino acids, haemoglobin, and certain brain chemical. Vitamin B6 also maintains blood glucose levels, affects the synthesis of specific brain chemicals, influences hormone activity levels, general brain development, immune function and steroid hormone activity. Vitamin B6 may be useful in the treatment of carpal tunnel syndrome and PMS.

Sources of Vitamin B6: Vitamin B6 or Pyridoxine is found in a variety of food items, some of its best sources are meat, poultry, eggs, bananas, fish, cereal grains and legumes, green and leafy vegetables nuts, liver and fruit.

Vitamin B6 Deficiency: Vitamin B6 deficiency is found in those people who consume excessive alcohol, women who are on the contraceptive pill, elderly people and those who suffer from thyroid disease. Symptoms of Vitamin B6 deficiency include insomnia, depression, anaemia, cracked corners of the mouth, confusion, dermatitis, smooth tongue convulsions, pink eye; neurological symptoms like epilepsy, irritability, depression, anxiety and muscle twitching. Large doses of vitamin B6 taken over a long period can lead to irreversible nerve damage.

Vitamin B7: Discovery, Sources, Role & Deficiency

Vitamin B7 is also known as biotin and is a cofactor for many enzymatic reactions needed for the synthesis of many fatty acids and in gluconeogenesis.

Discovery of Vitamin B7: Dean Burk was a co-discoverer of biotin.

Role of Vitamin B7: Biotin or Vitamin B7 plays a key role in the metabolism of lipids, carbohydrates, protein and fat. Vitamin B7 is involved in the synthesis of glucose. It is an essential beauty vitamin and supports healthy hair, skin and nails. High biotin intake can lead to a rise in cholesterol levels.

Sources of Vitamin B7: Biotin or Vitamin B7 is found in a number of food items, some of its best sources are cauliflower, egg yolks, peanuts, brewer’s yeast, strawberries, organ meat, cheese, poultry, mushroom and soybeans.

Vitamin B7 Deficiency: Biotin deficiency is rare as not only does the body produce a small amount of biotin itself, but is widely distributed in a number of food items. Moreover, the body requires only small amounts of biotin. Vitamin B7 deficiency is usually found in people, such as body builders who over a period consume large amounts of egg whites, because a protein in the egg white prohibits the absorption of biotin. Symptoms of Vitamin B7 deficiency include pale or grey skin, hair loss, nausea, dermatitis, muscle pains, cracked sore tongue, depression, nausea, weakness, hallucinations, abnormal heart actions, loss of appetite, dry scaly skin and fatigue. In infants, biotin deficiency may lead to impaired growth and neurological problems.

Vitamin B9: Discovery, Sources, Role & Deficiency

Vitamin B9 is also known as folic acid or folate and is a precursor needed to repair and synthesise DNA. Vitamin B9 aids the transfer of carbon units in the metabolism of nucleic acids and amino acids. Vitamin B9 is a cofactor in various reactions and is especially essential for rapid cell division and growth. Vitamin B9 or folic acid is the synthetic form of folate.

Discovery of Vitamin B9: In 1933, Lucy Wills discovered folic acid or vitamin B9.

Role of Vitamin B9: Folate helps in the formation of red blood cells that carry oxygen around the body. Its most important function is DNA synthesis and metabolism through methylation. Folic acid or Vitamin B9 is essential in fetal health and development, and development of the baby’s nervous system. Childbearing women should eat folate rich food in the initial stages of pregnancy to reduce the risk of neural tube defects such as spina bifida in the baby. Folic acid is used extensively in food fortification and dietary supplements.

Sources of Vitamin B9: Folate or Vitamin B9 is found in a variety of food some of its best sources being bread, cereal, citrus fruits, spinach, asparagus, green leafy vegetables, legumes, poultry, eggs, seeds, brewer’s yeast, liver, fortified orange juice, beets, dates and avocados.

Vitamin B9 Deficiency: The body produces some amount of folate itself, but it is insufficient. Vitamin B9 deficiency symptoms are weakness, fatigue, weight loss, macrocytic anemia, elevated levels of homocysteine and in pregnant women it may lead to birth defects. Folate is considered non-toxic, but excessive intake over a period can lead to irritability and intestinal problems.

Vitamin B12: Discovery, Sources, Role & Deficiency

Vitamin B12 is also known as cyanocobalamin and is a coenzyme involved and essential for almost every metabolic action in the body. Vitamin B12 is a cofactor for methionine synthase, which converts homocysteine to methionine, which in turn is used for the methylation of DNA.

Discovery of Vitamin B12: The knowledge of vitamin B12 has been developed over the years by research of various scientists.

Role of Vitamin B12: Vitamin B12 is essential for metabolism of carbohydrates, proteins and lipids. Vitamin B12 is closely related to folate and both depend on each other for their proper functioning. Vitamin B12 is critical in the process of cellular energy production and is needed for the formation of red blood cells, DNA synthesis and aids in normal nervous system functioning, as it maintains the myelin, which is the cover of the nervous cells.

Sources of Vitamin B12: Vitamin B12 is found in a variety of food items and its main sources are liver, egg, meat, milk, cheese, chicken, beef and fish. Almost anything of the animal origin is rich in vitamin B12.

Vitamin B12 Deficiency: Vitamin B12 deficiency is most commonly found in the elderly, vegans and breast-fed babies of vegan mothers; as vitamin B12 is mostly from animal sources and. Symptoms of are vitamin B12 deficiency include: vision loss, shortness of breath, pernicious anemia, macrocytic anemia, mania, psychosis, memory loss, cognitive defects, weight loss, loss of appetite, depression, anxiety and in advanced cases, paralysis.

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Pramod Kerkar

Written, Edited or Reviewed By:

, MD,FFARCSI

Pain Assist Inc.

Last Modified On: May 2, 2018

This article does not provide medical advice. See disclaimer

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