Vitamin B Complex Test Importance, Functions, Deficiency Causes, Symptoms, Food Sources, Diagnosis

Broadly, vitamin are classified as - Fat-soluble and Water-soluble. The fat soluble ones as named are stored in the fatty tissues of our body for months and are majorly absorbed from the gastrointestinal tract. These include vitamin A, D, E and K. On the contrary, the water soluble ones are easily expelled through urinary pH and not accumulated for long. These include the B complex group and vitamin.

Vitamin B Complex "Nature's super good gift for the ever working human body"

How many of us as kids had to drink medicated syrups everyday and have enjoyed the different tastes! Some of us may also have chewed on the colourful tablets everyday. In that young age, our parents must have fed these with utmost sineerity as doctor's prescription to prevent any kind of growth deficieney, Kids now a days are fussy about traditional foods and with increasing popularity and advertisements on junk, all the green leafy veggie diet has gone for a toss! Natures goodness continues to rest in your grandmother's recipe books, while quiek meals with supplement tablets, especially the advertised multivitamin ones have become a fad.

So what are these vitamins?
The word vitamin can be easily broken down to two words - Vital and Amine. Thus, vitamins are vital organic nutrients required in minute quantities for the growth, development as well as various Metabolic. What makes these organic compounds very significant is the inability of our body to synthesise many of these, thus pushing diet in the forefront!

A very important discovery in the field of medical science, the word "vitamine" was originally coined by Casimir Funk in the year 1912. With the current listed vitamins being thirteen, their discovery was chaperoned by many physicians, epidemiologists, chemists, etc. and the process is deemed to have been extremely slow yet progressive. With Carbohydrates, liver, Fats and Minerals being considered the pillars for good health, the discovery of these vitamins came with the study of conditions like rickets, scurvy, xerophthalmia, etc. which were detected to be not caused by any infectious condition or toxins. Chemists from many part of the world are the ones who studied, isolated and derived the chemical structure of these vitamins as we know from today

William Fletcher is credited with identifying vitamins as special factors which when removed from food caused disease conditions in the year 1905. In the year 1906, Sir Frederick Gowland Hopkins, an English biochemist also discovered important food factors for health. The vitamin hypothesis of deficiency disease hence has been credited to be together formulated by Hopkins and Funk.

Though the family of vitamins as well as the disorders triggered by their deficiency is large, this article is an attempt to introduce one big family - The B complex group.

Introduction to the B complex group
Elmer V. McCollum has been credited with the discovery of B vitamins between 1915 - 1916. Vitamin B 12 group constitutes of eight water soluble agents, similar in properties and acquired together through many dietary sources. Though these are actually twelve in number, eight of these are only considered to be essential and are to be obtained from diet while the rest which are choline, inositol, PABA (para-aminobenzoic acid) and lipoic acid are synthesised within our body.

The B complex though is a group of vitamins, each has a distinct structure and functionality in human body. Though it is a complex, the quantity of each nutriment required for our body is different ranging from 3meg to 18meg. Hence, equalising their intake does not work out to be beneficial.

Myth & Facts of Vitamin B complex

Myth vitamin helps in losing weight and even protects from mosquito bites.

Fact None of this is true. Vitamin B1 is necessary for growth and development of cells, but can never help in losing weight and definitely does not protect from mosquito bites!

The essential eight in this family include:
' Vitamin B1 - Thiamine
' Vitamin B2 - Riboflavin
' Vitamin B3- Niacin
' Vitamin B5 - Pantothenic acid
' Vitamin B6 - Pyridoxine
' Vitamin B7 - Biotin
' Vitamin B9 - Folic acid
' Vitamin B12 - Cobalamine
The numbers are not continuous as many of the intermediate ones were later detected not to be vitamins or were non-essentials or duplicates.

How to obtain these vitamins?
As mentioned earlier, these essentials are not synthesised within the body and hence external supplementation - both through diet and pills become the option. Natural dietary sources include dairy products and fresh meat apart from leafy vegetables and nuts. Boiled vegetables provide B complex vitamins with ease and since many of them are light and temperature sensitive, subjecting these to freezing temperatures or direct sunlight can destroy them.

Deficiency of one particular B vitamin is very rare and hence usually multivitamin tablets are recommended for treating it. Multivitamins are touted to be better than pure B complex supplements for a wholesome nutrient gain. These supplements are available both in the form of pills and injectables.

Vitamin B complex functionality and links The vitamin B complex group has been linked to many functionalities in human body right from synthesis of complete blood count to maintaining heart health, strengthening immunity and also protecting the unborn fetus. The quality of hair, skin and nails is also maintained by these nutriments. Many are also important coenzymes which facilitate metabolic processes. Recent studies have also indicated homocysteine (a robust heart health marker) levels appear to improve well with adequate quantities of vitamin B6 and Vitamin B 12.

Symptoms of insufficiency and risk factor for vitamin B complex
The deficiency of vitamin B complex is generally symptomised with:
1. Neurological issues like memory loss, confusion, irritability, etc.
2. Tiredness and fatigue
3. Nausea and poor appetite
4. Skin lesions
And many more...

The causal factors for vitamin B complex deficiency include:
1. Impaired absorption due to lifestyle factors like smoking, alcoholism, etc.
2. Certain genetic condition or pre-existing disorder which can affect metabolism
3. A pure vegetarian diet as meat is a rich source for these
4. Age especially in the elderly since these are absorbed from the food consumed
5. Under treatment of certain medications like cortico steroids, pyrimidine antimetabolites like 5-fluorouracil during chemotherapy, colchicine, methotrexate, etc. which affect their absorption.

Vitamin B1 This vitamin was discovered by Casimir Funk in 1912. Thiamine or aneurine is the first B vitamin to be discovered and is present in the human body both as free thiamine or in various phosphorylated forms like thiamine monophosphate, triphosphate and pyrophosphate (TMP, TTP and TPP). TPP is the active form involved in several biochemical pathways like carbohydrate metabolism, fatty acids, etc.

Causes of deficiency
Poor dietary intake
Reduced intestinal
Excessive loss or excretion of thiamine (diuretic induced, hemodialysis)
Diabetic patients who have altered glucose metabolism have been shown to harbour low serum thiamine levels
Individuals affected with Malaria, HIV, etc. have been found to harbour an increased risk of deficiency development

Deficiency disorders Beriberi is the condition that results due to acute thiamine deficiency and affects multiple organs along with the nervous system. Another condition, Wernicke's encephalopathy, a neurological disorder is a secondary complication arising out of deficiency. There are different forms of beriberi viz. 'dry form' characterised by neuropathy and 'wet form' wherein along with neurological manifestation there is profound cardiovascular manifestations like edema, rapid heart beat, and cerebral beriberi which leads to Wernicke's encephalopathy especially, in individuals under the influence of alcohol abuse. If untreated, it can lead to irreversible neurological damage.

Gastrointestinal beriberi characterised by nausea, vomiting and severe abdominal ache is caused due to accumulation of lactate (lactic acidosis) fueled by a decrease in the activity of TPP.

Sources The recommended safe intake of thiamine in adults is 1.2 mg/day for males and 1.1 mg/day for females. Animal sources - Fish (trout), lean pork, etc. Plant - Nuts like macadamia, sunflower seeds, wheat, green peas, asparagus, navy beans, etc.

D.T. Smith and E.G. Hendrick have been credited with its discovery in the year 1926. It is a very important component of coenzymes; flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN). These are involved in redox reactions critical in metabolism pathways. Riboflavin also indirectly aids in antioxidant reactions as many of these are FAD dependent pathways.

Causes of deficiency Alcoholism is the primary cause that can lead to deficiency as it impairs absorption as well as utilisation
Certain other conditions like lactose intolerance as well as anorexia may lead to decreased intake of riboflavin

Deficiency disorders Deficiency of riboflavin alone is rarely found as an isolated case as it generally occurs with the B complex deficiency in totality. Ariboflavinosis (clinical name for riboflavin deficiency) causes sore throat, skin inflammation with scales, redness of tongue, etc. Some studies have also shown riboflavin deficiency in pregnant women increases risk of preeclampsia by 4.7 times." Corneal crosslinking used for strengthening cornea of the eyes involves use of riboflavin with UV irradiation.

Sources The recommended safe intake of riboflavin in adults is 1.3 mg/day for males and 1.1 mg/day for females. Vitamin B2 is highly light sensitive and occurs in most of the plant and animal foods. Milk, cheese, egg, almonds, spinach, chicken, fortified wheat and cereals are few which harbour this.

Vitamin B3/Niacin This vitamin was discovered by Conrad Elvehjem in the year 1937. Niacin and nicotinamide are very important precursors for formation of the redox and non-redox reaction fueling agent NAD (nicotinamide adenine dinucleotide). NAD is also a very important substrate for DNA repair enzymes.

Causes of deficiency
- Insufficient dietary intake
- Conditions like anorexia and obesity
- Indulging in diet rich in maize and poor in animal proteins
- Long-term treatment with antitubercular agents, anticancer drugs, dialysis, etc.

Deficiency disorders Severe niacin deficiency leads to Pellagra. It is generally found to be rampant in populations wherein the staple diet is of sorghum or corn. The three D's - Dementia, Diarrhea and Dermatitis mark symptoms of deficiency. Death which marks the fourth D can also occur if the condition remains untreated.

Sources The recommended safe intake of niacin in adults is 16mg NE/day for males and 14 mg NE/day for females (NE - Niacin equivalent). Animal products like beef, tuna, turkey and also others like lentils, peanuts, etc. are good sources of niacin.

Vitamin B5/Pantothenic acid This is a very important precursor for synthesis of coenzyme A important in many biochemical reactions like the citric acid cycle, drug metabolism in liver, synthesis of essential fatty acids, etc. Few studies have also shown it to have wound healing properties.

Causes of deficiency Since, this vitamin is synthesised by the gut bacteria and is also present in a wide variety of food materials, deficiency as such is very rare unless in cases of severe malnutrition. Deficiency disorders Insufficiency of this vitamin is very rare and is accompanied with symptoms like tingling sensation in hands and feet, headache, fatigue, etc.

Deficiency disorders Insufficiency of this vitamin is very rare and is accompanied with symptoms like tingling sensation in hands and feet, headache, fatigue, etc.

Sources The recommended safe intake of vitamin B5 in adults is 5 mg/day as per the Food and Nutrition Board of the Institute of Medicine. Whole unrefined grains are good source of vitamin B5 apart from milk, yoghurt, broccoli, sweet potatoes, etc. Animal products like pork, chicken, shellfish as well as egg yolk are also equally good. The intestinal bacteria also produce this essential vitamin.

Vitamin B6/Pyridoxine Paul Gyorgy is credited with its discovery in the year 1934. Vitamin B6 as well as its active derivative pyridoxal 5' - phosphate aid in functioning of more than 100 enzymes involved in protein metabolism, red blood cells and Amino acids biosynthesis gluconeogenesis, etc. It is also important for synthesis of neurotransmitters, nucleic acid biosynthesis, tryptophan metabolism, etc.

Causes of deficiency Though deficiency is very rare, it can occur in alcoholics, impaired metabolism, etc.

Deficiency disorders Deficiency is generally manifested by symptoms like irritability, confusion, depression, inflammation of tongue, mouth ulcers, etc.

Sources The recommended dietary intake of pyridoxine in adults is 1.3 mg/day while in older adults (> 51 years) it is 1.7 mg/day for males and 1.5 mg/day for females. Plant foods like banana, dried plums as well as animal products like chicken, turkey, salmon and fortified cereals are touted to be good sources for this vitamin. Toxicity has also been noted due to excessive supplementation and hence the tolerable upper limit for adults is set at 100 mg/day and is manifested with painful neurological symptoms.

Vitamin B7/Biotin Biotin in the initial stages after its discovery was studied on for many years before being classified as a vitamin and its biological role involves biotinylation; i.e. being associated with the active site of the enzyme carboxylases. The family of carboxylases are involved in many essential biochemical pathways like gluconeogenesis, fatty acid synthesis, metabolism of amino acids, etc. Biotin is associated with histones which are proteins which pack DNA. Naturally B7 is synthesised only by bacteria, yeast, certain plant species, etc.

Causes of deficiency Though deficiency is very rare, insufficient dietary intake becomes the primary cause for the same Deficiency can also be fueled by hereditary condition, biotinidase deficiency (which hampers intestinal absorption), prolonged consumption of raw egg, etc.

Deficiency disorders Hair loss is one of the biggest signs of biotin deficiency apart from others like hallucinations, depression, tingling sensation in the extremities, etc. Hereditary deficiency causes also weaken the immune system of the affected individual predisposing them to a lot of bacterial and fungal infections.

Sources The recommended dietary intake of vitamin for adults is 13 meg/day. Many dietary agents like bread, cheese, egg, etc. are rich in biotin apart from the normal gut bacteria which produce the same.

Myth & Facts

Myth: Vitamin B6 helps in treating anemia

Fact: Vitamin B6 has no relation with treating anemia. Scientific evidences have also failed to prove that it can treat asthma.

Vitamin B9/Folic acid This vitamin was discovered by Lucy Wills in the year 1933. It is a very crucial component for multiple clinical functions like metabolism of nucleic acid precursors and amino acids, in brain development, cognitive functions, etc. It is one of the major vitamins fortified in a lot of dietary supplements as well as in synthesised food stuffs.

Causes of deficiency Dietary insufficiency is the primary and most popular cause for folate deficiency. Lifestyle habits like chronic alcoholism, Smoking, etc. also hampers its absorption. Pre-existing conditions like inflammatory bowel disease, celiac disease, as well as genetic mutations which affect its absorption, metabolism, etc.

Deficiency disorders anemia, specifically megaloblastic is one of the serious conditions which arises due to folate deficiency. This causes fatigue, weakness, etc. However, this condition, is reversible with nutrient supplementation. Pregnant women are advised to take folate supplements even in the pre-pregnancy stage to avoid development of neural tube defects in the unborn child.

Sources The recommended dietary intake for adults is 400meg/day. Green leafy vegetables like spinach, legumes, citrus fruits as well as fortified foods are good sources for folate. However, deficiency can be avoided or best treated only with supplements, especially in pregnant women.

vitamin b12/Cobalamine Cobalamine is so called as the chemical structure of the vitamin bears an iron as well as cobalt ion. It is a very crucial vitamin for folate and homocysteine metabolism, the increased levels of the latter being associated with risk of cardiovascular diseases. It also exerts a protective effect on DNA integrity as well as myelin sheath of neurons along with involvement in synthesis of neurotransmitters, etc.

Causes of deficiency Inspite of sufficient dietary intake, deficiency can be caused by malabsorption, dysfunction of organs like pancreas, small intestine, etc. Conditions like pernicious anemia an autoimmune condition, inflammatory condition like atrophic gastritis, etc. are also the most popular causes for deficiency.

Deficiency disorders Apart from elevation in blood homocysteine levels, it causes folate deficiency which hampers DNA synthesis, as well as dementia, memory loss, mood changes, etc. Deficiency is also documented to damage the myelin sheath of neurons, loss of appetite, etc.

Sources The recommended dietary intake for adults is 400meg/day. Green leafy vegetables like spinach, legumes, citrus fruits as well as fortified foods are good sources for folate. However, deficiency can be avoided or best treated only with supplements, especially in pregnant women.

Sources The recommended dietary allowance for adults is 2.4 mcg/day. Cyanocobalamine is the form which is more popularly used for fortification purposes. Foods from animal sources are naturally rich in B12. Hence, vegetarians have an increased risk of developing deficiency and involving supplements becomes essential. Apart from bacteria which can synthesise B12, other sources include poultry, fish, beef, etc.

Indians and vitamin B deficiency Micronutrient deficiencies like iron deficiency anemia, Vitamin D, etc. are a growing concern in India Deficiency of vitamin B complex is easy to creep in our system as these being water-soluble are easily leached away from the system, and hence require to be included almost daily

Few studies have recorded deficiency status of many B complex vitamins in Indian population. A study by Taneja el al. (2007) has recorded vitamin B12 deficiency to be prevalent in 80% preschool children, while 70% of Indian adults have been identified to harbour the same. Many reports have also highlighted vitamin B12 deficiency to be high among Indians due to both dietary preferences and socioeconomic conditions as well as increased age which poses risk for Helicobacter pyroll infection.' Dietary studies have also highlighted individuals consuming more of a cereal based diet hardly ingest 75 ug folate each day.'

Testing modalities for Vitamin B complex Vitamin B complex deficiency can be easily treated with appropriate supplementation strategies and to determine the need, it is necessary to get tested. Technological advancements have gifted mankind many platforms to accurately quantify the levels of these in serum.

Platforms like chemiluminescence immunoassays (CLIA) are available to assess levels of individual B vitamins like B12, folic acid, ete. Also, analytical platforms like LC-MS (Liquid Chromatography - Mass Spectrometry) are available these days for superior quality analysis in which all the eight vitamins can be validated for estimation in a single shot.

Understand management - Pros/Cons Toxicity due to the B complex group is very rare and deficiency management becomes important. Identifying symptoms especially the physical manifestations is important. Deficiency management varies depending on age, gender, dietary preferences, pre-existing health conditions, treatment if any, etc. Pregnant women, breastfeeding mothers, individuals recovering from physical injury or trauma generally exhibit higher requirements for vitamin B. Treatment with antibiotics has also shown to affect levels of B vitamins by killing the good microbes which synthesise them.

Diet and supplements are the only source for B vitamins as discussed earlier. Toxicity can occur due to oversupplementation. Liver inflammation has been noted in cases wherein niacin ingestion is more than 500mg each day. This over consumption also triggers gout, affects sugar control in Diabeties, lower blood pressure, ete. Pyridoxine in high doses has been attributed to cause damage to the nervous system and liver inflammation.

To conclude.. A well-balanced nutritious diet is the key for good health and vitamins definitely form an important cog in that wheel. The vitamin B complex group is definitely a blessing in all senses for a stress-free life!

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