B Complex Vitamins: Cellular Energy

The B vitamins are a class of related water-soluble amino acids (the word "vitamin" is a portmanteau of "vital aminos") that are vital to the cellular processing of energy. If you have a deficiency in any of the B vitamins, you are more likely to suffer from weakness and lethargy than anything else.

The B vitamins are thiamin, riboflavin, niacin, pantothenic acid, biotin, vitamin B6, folate, and vitamin B12. Each one has a critical role, but all work in ways that ensure your body gets the energy it needs.

* Thiamin is active in critical cellular energy processes in your nerves and muscles.
* Riboflavin helps release energy from nutrients in all the cells in your body.
* Niacin helps metabolize glucose, fat, and alcohol -- energy-transfer reactions.
* Pantothenic acid is a critical part of an energy-metabolism coenzyme.
* Biotin acts in a critical energy cycle and helps synthesize glucose.
* Vitamin B6 is critical for synthesizing amino acids. It is different from the other B vitamin in that it is stored in muscle tissue, and also in that alcohol destroys it.
* Folate supports B12 in its actions and -- more importantly -- synthesizes DNA for rapidly growing cells. Its second function makes it vital for healthy development of a fetus.
* Vitamin B12 supports the healthy maintenance of nerves and bones. Most used vitamin B12 is reabsorbed by the body, making it hard to have a deficiency.

All B Vitamins

The one thing all B vitamins seem to have in common is an energy-boosting action. A deficiency of any of the B complex of vitamins results in fatigue as a primary symptom. For this reason, B vitamin supplements are often marketed as energy boosters, or included in energy drinks.

This makes sense in the fairly unlikely case that you have a B deficiency, but if you have adequate vitamin B intake daily, more vitamin B than you need can lead to toxicity -- which often leads to fatigue. In other words, if you take too much, you can worsen the very symptom you're trying to cure.

Because of its actions on nerves, megadoses of vitamin B12 are often marketed as a treatment for carpal tunnel disease. I've used it, and it works for me. But still, taking too much of it can lead to a worsening of symptoms. It's wisest to take large doses for a limited amount of time, until the symptoms subside, and then taking lesser amounts.

B vitamins act in concert in metabolizing energy; a deficiency in one may mask as a deficiency in another. For this reason, most B vitamin supplements include all the varieties of vitamin B to cover you completely.

The Least You Should Know

All vitamin Bs are water-soluble, so supplements should be taken with at least a full glass of water. They are better synthesized by the body if you eat a nutritious meal before you take them.

Each of these vitamins has a different recommended daily dose. Any multivitamin providing all the B complex should have a full daily dose. It's actually more important to watch for overdoses from the few B vitamins that have an identified toxicity level.

Some B complex supplements actually give you a toxic-level overdose of certain B vitamins; others give you the maximum nontoxic level, which means drinking energy drinks or otherwise consuming items that contain B vitamin will result in a toxic overdose.

Max recommended doses:

Niacin: 35 mg/day for adults
Vitamin B6: 100 mg/day for adults
Folate: 1000 micrograms/day for adults

The other B vitamins have not had a maximum dose identified.

Every B vitamin (with the possible exception of B6) must be taken daily for good health; the body does not carry reserves. In the normal course of things, supplements aren't necessary; however, pregnant women need more folate, and people with an alcohol problem should probably take a B complex to replace vitamins destroyed by alcohol.