There's just one A vitamin. Same for C, D, E, and K. Vitamin B, however, has its own complex, which consists of eight B vitamins: thiamine (B1), riboflavin (B2), niacin (B3), pyridoxine (B6), folic acid (B9), cyanocobalamin (B12), pantothenic acid and biotin. Most multivitamins contain all of these B vitamins, but you may also choose to pick up a B complex supplement if you are pregnant and need extra folic acid, or if you are nursing and need more of all the B vitamins.

B vitamins are water-soluble (like C), which means that there is a much smaller danger of liver damage or toxicity than there is with the fat-soluble vitamins. These other vitamins are stored in the liver and cannot be excreted like B and C--which are also stored in the liver, but mostly pass out of your body in your urine if you take too much of them. Of course this doesn't mean that you should swallow a couple of capsules daily for no good reason, but it is a relief to realize that if you have taken an unregulated supplement, you will probably be okay.

Vitamin B in Your Body

The B vitamins are very powerful, and involved in almost everything that happens in your body. They can help treat major diseases such as coronary heart disease. They help provide energy by breaking down carbs, and they also help break down fats and proteins. They also help with muscles tone, skin, and ocular health.

B2 and B3 have a lot to do with healthy skin. Insufficient levels of riboflavin can cause forms of dermatitis, as well as inflammation of the skin around the mouth and nose. A biotin deficiency can also lead to an increased susceptibility to dermatitis. If your diet is short on B vitamins, pick up a supplement from your local or online pharmacy and your whole body will thank you!