Vitamin B Deficiency and Toxicity

There’s a misconception that B-group vitamins provide the body with fuel for energy. Truth is, the body uses energy-yielding nutrients such as Carbohydrates, Fat and Protein for fuel and the B-group vitamins help the body to use that fuel by activating the necessary reaction and when making new DNA.

Although most Vitamins daily requirement amount is small but Vitamin B is a water-soluble and gets lost easily in the process of food preparation. Furthermore, most people do not consume a variety of food in moderation hence, deficiencies and toxicities do happen. 

Here’s what happens when there’s a deficiency or toxicity of the B-group vitamins:

Vitamin B1 (Thiamine)

Deficiency: Generally found in countries where the dietary staple is white thiamin, vitamin b1, rda, daily requirement, vitamin requirementrice. Deficiencies in the Western world are generally caused by excessive alcohol intake and/or a very poor diet. Symptoms include confusion, irritability, poor arm or leg (or both) coordination, lethargy, fatigue and muscle weakness. Serious deficiency may results in diseases such as edema beriberi and Wernicke-Korsakoff syndrome. The secondary cause could be due to increased demand of Thiamine due to hyperthyroidism, pregnancy, or fever. In alcoholics, many mechanisms contribute to thiamin deficiency as well. They include impaired absorption (such as prolonged diarrhea) and  metabolism (such as heptic insufficiency), and possibly an apoenzyme defect. 

Toxicity: Possible anaphylaxis caused by high-dose thiamin intravenous injections. However, the doses were greater than the quantity humans can physically absorb from oral intake.


Vitamin B2 (Riboflavin)vitamin b2, vitamin b2 requirement, riboflavin requirement

Deficiency: causes an inflammation of the tongue known as ariboflavinosis. Other symptoms may include cracks in lips (cheilosis), high sensitivity to sunlight, inflamed eyelids, seborrheic dermatitis (flaky scalp), pharyngitis (sore throat), hyperemia, and oral ulcers.

Cause: Riboflavin is easily destroyed by UV rays but not cooking. Hence, milk is  packed in opaque packaging and fortified with Vitamin D. People with Lactose Intolerant should supplement Riboflavin with dark green leafy vegetables.


Vitamin B3 (Niacin or Nicotinic acid)

Deficiency: usually caused by the absence of Vitamin B3 in the diet and may result in pellagra which vitamin b rda, vitamin requirements, vitamin b3causes symptoms such as diarrhea, dermatitis, dementia, insomnia, mental confusion, and death.

Toxicity: Intake of 3000 mg/day of nicotinamide and 1500 mg/day of nicotinic acid are associated with nausea, vomiting, and signs and symptoms of liver toxicity. Other effects may include glucose intolerance, and (reversible) ocular effects. Additionally, the nicotinic acid form may cause vasodilatory effects, also known as “Niacin Flush”, including redness of the skin, often accompanied by an itching, tingling, or mild burning sensation, which is also often accompanied by pruritus, headaches, and increased intracranial blood flow, and occasionally accompanied by pain. Medical practitioners prescribe recommended doses up to 2000 mg per day of niacin, usually in time release format, to combat arterial plaque development in cases of high lipid levels.vitamin b5, pantothenic acid, vitamin b5 rda


Vitamin B5 (Pantothenic acid)

Deficiency: this deficiency is rare. It results in acne and paresthesia, although it is uncommon. Extreme symptoms involve a general failure of all the body’s systems and include fatigue, GI distress, and neurological disturbances.


Vitamin B6 (Pyridoxine, pyridoxal, pyridoxamine)

Deficiency: affects the synthesis of key neurotransmitters, and abnormal compounds produced during tryptophanPyridoxine, pyridoxal, pyridoxamine, vitamin b6, vitamin b6 requirement
metabolism accumulate in the brain. Early symptoms of deficiency include depression and confusion; advanced symptoms include abnormal brain wave patterns and convulsions.

Causes of deficiency: Alcohol contributes to the destruction and loss of Vitamin B6 from the body. Another Vitamin B6 antagonist is INH, a medication used to treat tuberculosis. Oral contraceptives may create a shortage of vitamin B6 by stimulating the breakdown of tryptophan, a process that requires the vitamin.

Toxicity: large doeses of vitamin B6 taken for months or years may cause irreversible nerve degernation.

Causes of toxicity: Some women use Vitamin B6 supplements in an attempt to treat pre-menstraul syndrome (PMS) while some take Vitamin B6 supplements in an attempt to cure carpal tunnel syndrome and sleep disorders.

biotin, vitamin b7, vitamin deficiency


Vitamin B7 (Biotin)

Deficiency: may lead to impaired growth and neurological disorders in infants caused by multiple carboxylase deficiency, an inborn error of metabolism, can lead to biotin deficiency even when dietary biotin intake is normal. Taking more than 2 dozen egg whites for several months may induce biotin deficiency which results in symptoms such as skin rash, hair loss, and neurological impairment. 


Vitamin B9 (Folic acid)

folate, folic acid, vitamin B, pregnant, breastfeed, Deficiency: impairs cell division and protein synthesis – processes critical to growing tissues. The first symptoms of this deficiency are macrocytic anemia and GI tract deterioration. This deficiency also causes elevated levels of homocysteine which increase the risk of fatal heart disease by clotting blood and deterioration of arterial wall. 

Effects of Folate deficiency in Pregnant Women: Researches have shown that folic acid might also slow the insidious effects of age on the brain. Deficiency in pregnant women can reduce the risks of neural tube defects. 

Causes of deficiency: Folate deficiencies may develop from inadequate intake, impaired absorption or an unusual metabolic need for vitamin e.g. pregnancies involving twins and triplets, cancer, chicken pox, GI tract damage, etc. Folate is also very vulnerable to interactions with drugs. Some medications displace the vitamin from enzymes and interfere with normal metabolism e.g. anti-cancer drugs, aspirin and antacids. Oral contraceptives may also impair folate status, as may smoking.

Toxicity: lead to permanent neurological damage.

Vitamin B12 (Cyanocobalamin)vitamin b12, vitamin b, vitamin RDA

Deficiency: results in a macrocytic anemia, elevated homocysteine, peripheral neuropathy, memory loss and other cognitive deficits. It is most likely to occur among elderly people, as absorption through the gut declines with age; the autoimmune disease pernicious anemia is another common cause. It can also cause symptoms of mania and psychosis. In rare extreme cases, paralysis can result.

Cause: damage to cells of the stomach developing atrophic gastritis or pernicious anemia, which may be due to an inherited defective gene.

Toxicity: results in skin, spinal lesions, and Acne-like rash

Here are the Top 10 foods to include in your meals for a Vitamin B rich diet:

vitamin B, food rich in Vitamin B

Find out more about What is Vitamin B, its effects and benefits to our body.

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What is Vitamin B?

There are 13 vitamins that our body needs, and eight of which are made up from the B-group vitamins. Vitamin B is a complex of eight water-soluble B-group Vitamins, all of which are essential for bodily functions such as metabolism of energy and amino acids, support of immune system, ensuring healthy pregnancies and regeneration of red blood cells. Mtabolism is the body’s work, and the B-group vitamins are indispensable in every step.

Vitamin B1 (Thiamine)Vitamin B, Thiamin, Vitamin B1, athletes, recovery

Thiamine plays a prominent role in breaking down carbohydrates to release energy. Consuming more B1 can help reduce fatigue, and can be especially useful for athletes.

Thiamine is also required to support a healthy immune system too. Thiamin occupies a special site on the membranes of nerve cells. Consequently, processes in nerves and in their responding tissues, the muscles, depend heavily on thiamin.

Vitamin B2 (Riboflavin)

Riboflavin is an antioxidant, which helps to prevent cell damage particularly in the skin. It supports blood production, the immune system, and breakdown of food for energy. Consuming 400mg of riboflavin daily has been shown to reduce the frequency of migraines.

Vitamin B3 (Niacin or nicotinic acid)

Niacin participates in numerous metabolic reactions in the body. It is central in energy-transfer reactions, especially the metabolism of glucose, fat, and alcohol. It also boost your levels of High Density Lipids (HDL; good cholesterol). Regular consumption of alcoholic beverages interferes with the absorption of niacin which could affect the immune system and energy generation of the body.

Vitamin B5 (Pantothenic acid)

Pantothenic Acid is involved in more than 100 different steps in the synthesis of lipids, neurotransmitters, steroid hormones, and hemoglobin (blood cells). It serves as a compound in several metabolic pathways. Adequate consumption of Pantothenic Acid reduces thinning and graying of hair, as well as reduces acne.

Vitamin B6 (Pyridoxine, Pyridoxal, Pyridoxamine)

Vitamin B6 helps with sleep and prevents depression as it is involved in the production of neurotransmitters that regular sleep and mood, such as serotonin, norepinephrine, dopamine and melatonin. In addtion, pyridoxine is vital in the production of red blood cells and amino acid metabolism.

Research has shown that vitamin B6 influences congnitive performance, immune function, and steroid hormone activity. Unlike other water-soluble vitamins, vitamin B6 is stored extensively in muscle tissue.

Vitamin B7 (Biotin)

Biotin plays an important role in metabolism as a coenzyme which serves in energy metabolic processes. It also plays crucial roles in gluconeogenesis (synthesis of glucose from non-carbohydrate sources), fatty acid synthesis, and the breakdown of certain fatty acids and amino acids. Though it is needed in very small amounts, it’d contributes to healthier skin, hair and nails.

Vitamin B9 (Folic acid/ Folate)

folate, healthy baby development, pregnant, pregnancy, vitamin B, folic acid

Folate helps convert Vitamin B12 to one of its coenzyme forms and helps synthesize the DNA required for all rapidly growing cells. It is also involved in many amino acid metabolism reactions which prevents anemia and slow memory loss too.

It is a critical B vitamin for pregnant women to prevent birth defects. Several research studies have confirmed the importance of folate in reducing the risks of neural tube defects. The brain and spinal cord develop from the neural tube, and defects in its orderly formation during early weeks of pregnancy may result in various central nervous system disorders and death.

Folate has an important role in defending against heart diseases too. One of folate’s key roles in the body is to break down this amino acid known as homocysteine. Without folate, homocysteine accumulates, which seems to enhance blood clot formation and arterial wall deterioration.

Vitamin B12 (various Cobalamins; commonly Cyanocobalamin or Methylcobalamin)

Vitamin B12 and folate are closely related: each depends on the other for activation of metabolism and enzymatic reactions.

The regeneration of the amino acid methionine and the synthesis of DNA and RNA depend on both folate and vitamin B12. In addition, without any help from folate, vitamin B12 maintains the sheath that surrounds and protects nerve fibres and promotes their normal growth. Bone cell activity and metabolism also depend on vitamin B12.

Most of these vitamins can’t be stored by the body and have to be consumed regularly in our diet. B12 is found primarily in foods derived from animals. As these vitamins are water-soluble, they are loss or easily destroyed when cooking or processing food. Extended cooking, food processing and alcohol can destroy or reduce the availability of these vitamins.

Include these foods in your meals for a balanced diet packed with Vitamin B:

vitamin B, thiamin, niacin, biotin, riboflavin, b12, folate

Find out more about Vitamin B deficiency and toxicity.

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