Vitamin B complex describes a family of 8 water-soluble vitamins which all play important roles in metabolism. In this article only a very general overview will be presented.

Originally people thought that Vitamin B was a single compound, but actually many components have been identified, all coexisting in the same foods – hence the term ‘complex’. We also now know that all the components are important and are required in certain ratios to be fully beneficial.

Whole grains are a vital source of all these vitamins. However, the outer covering of the grain must still be present and refined brains have lost most of their nutrient value.

Other good sources are green leafy vegetables and Brewer’s yeast.

To see the importance of whole grains as a source of Vitamin B Complex, check back to the food pyramid on our Nutrition and Food Page.

What the B Vitamins do

The B vitamins are necessary for a variety of major biochemical functions including:

* The production of energy by converting complex carbohydrates to glucose and then to carbon dioxide and water.

* The metabolism of fats and proteins which is essential for good health, notably the nervous system.

* Healthy skin, hair, eyes and muscle tone.

Early signs of deficiency

Early signs of deficiencies are poor skin and hair condition, fissures at the corners of the mouth and nose, premature greyness and premature wrinkles – all to be avoided if at all possible!

The components of Vitamin B Complex

A summary of the vitamins present in the B complex is presented below, together with a brief outline of their major metabolic functions.

(You might be wondering about the numbering system – why are there gaps? The reason for this is that many other compounds have been identified over the years that were originally thought to be part of the complex.

Some have since been found not to be essential for humans, others are required by other organisms, and yet others have not been found to have any nutritional value. For this reason they have been removed from the complex.)

B-1 Thiamine

Thiamine forms the coenzyme TPP which is required for a few very important enzymes involved in energy production and DNA and RNA synthesis.

It is essential for health of the nervous system and the brain, the digestive system and proper muscle function.

Deficiencies cause weakness and pains in the arms and legs, emotional disturbances, oedema, irregular heartbeat, poor concentration and memory, constipation.

B-2 Riboflavin

Roboflavin forms the coenzymes FAD and FMN, also essential for energy production from fats, sugars and protein.

It is essential for a healthy skin, hair, nails and eyes; it regulates body acidity and is also involved in the metabolism of drugs and toxins.

Deficiencies cause cracked lips and an inflamed tongue and skin problems; sensitivity to bright light; bloodshot, scratchy eyes; cataracts and split nails.

B-3 Niacin

Niacin forms the coenzymes NAD and NADP which are involved in over 200 enzyme reactions.

Itsi essential for energy production and synthesis of macromolecules like proteins; maintains a healthy skin, nervous system and digestive system.

Deficiencies cause skin problems such as acne and eczema, diarrhoea, insomnia, mental confusion, anxiety, tension, lack of energy, depression, bleeding and tender gums, headaches and migraines.

B-5 Pantothenic acid

Essential to all forms of life for normal growth and development; forms coenzyme A (CoA) which is necessary for energy production; involved in the synthesis of fats, cholesterol and hormones, neurotransmitters and haemoglobin; healthy skin and hair.

Deficiencies cause cramps and muscle tremors, burning feet, nausea and vomiting, apathy and poor concentration, lack of energy, teeth grinding and (rarely) acne and prickly, tingling sensations on the skin.

B-6 Pyridoxine

The most important coenzyme from pyridoxine is PLP (pyridoxal 5’-phosphate), necessary for the function of about 100 different enzymes; protein digestion and utilisation; brain function; hormone production; health of red blood cells, the nervous system and the immune system; controls allergic responses.

Deficiencies cause anaemia, high blood pressure, high homocysteine levels (a sign of heart disease), skin problems, muscle cramps and tremors, oedema, depression, nervousness and irritability, tingling hands.

B-7 Biotin

Biotin is essential for the activity of 5 human (mammalian) enzymes called carboxylases each of which is responsible for a vital metabolic reaction; involved in the breaking down of proteins and carbohydrates, and in making hormones; essential for fat utilisation; health of skin, hair, nails.

Deficiency symptoms include dry skin, skin ailments such as eczema, poor hair condition and premature greying, poor appetite, nausea and in infants impaired growth and neurological disorders.

B-9 Folic acid

Folic acid coenzymes are essential for synthesis of DNA and RNA and proteins; essential for red blood cell production; development of brain and nerves during pregnancy; ongoing health of brain and nerves.

Deficiencies cause anaemia, birth defects (e.g. spina bifida), elevated homocysteine levels, brain deterioration with age, eczema, cracked lips.

B-12 Cobalamin

Cobalamin coenzymes are essential for growth and development; necessary for the production of energy from fats and proteins; synthesis of haemoglobin which carries oxygen to the cells; DNA synthesis; necessary for growth and development, red blood cell production and the function of the nervous system; breaks down toxins including chemicals from tobacco smoke.

Deficiencies cause anaemia, pale skin, mental problems (e.g. memory loss, irritability, anxiety, tension, mania, psychosis) elevated homocysteine levels, peripheral neuropathy (muscle weakness, atrophy, lack of energy, pain and numbness), poor hair condition, eczema.

Intake of Vitamin B Complex

Ideally, all the B vitamins need to be present in one’s diet in the proper ratio for optimal uptake of each member of the family.

A varied diet is a good starting point, but to be certain that you are getting all that you need it is best to take a good, well-balanced Vitamin B complex.

The B vitamins are water soluble, and are not stored in the body, so they need to be supplied on a daily basis.

They are generally considered to be non-toxic, except for Vitamin B6 which should be limited to 500 mg per day. Too much can cause neurological disorders such as night restlessness and disturbing dreams.

Since the vitamins are water soluble, any excess would be excreted in the urine. This is normally visible as a brighter than usual yellow colour (caused by excess Vitamin B2)!

What you need to consider is whether a slight spill-over is preferable to any chance of deficiency. I know which option I prefer!

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