Monday, February 4, 2008

The A - Z of Vitamin B

Introduction
Some of the B vitamins are familiar names to us: niacin, riboflavin, thiamin, folic acid. We recognize the names and you?ve probably heard some of their benefits, but for many of us the details are a little unclear. What do they do? Where do we get them from? Are we getting enough? All will be revealed.

There are a series of B vitamins and they all play important roles in the body. The B vitamins are all essential for your health and work closely together. They are known by their common names, but also by a confusing number system - B1, B2, B3, B5, B6, B7, B9 and B12. The numbers would be fine if it weren?t for the fact that numbers 4, 8, 10 and 11 are missing! These numbers were given to discoveries that later turned out not to be vitamins, or turned out to be the same as B vitamins which had already been given numbers. Most often these days the B vitamins are referred to by name to avoid confusion.

What are they and what do they do?

Thiamin (B1) — An all-rounder
Thiamin plays a very important role in the process by which glucose in the blood is converted into energy the body can use. Also important in the formation of red blood cells, in proper nerve growth and function and in muscle. Deficiency leads to the condition known as "beriberi" (means great weakness in Singhalese). The most common reason for deficiency is alcohol abuse.

Recommended Daily Allowances

  • Adult men 1.2 ? 1.5 mg per day
  • Adult women 1.0 ? 1.5 mg per day
  • + 0.4 mg during pregnancy
  • + 0.5 mg if breast-feeding
  • Chronic alcoholics 10 ?100 mg per day


High doses appear to have no adverse effects

Riboflavin (B2) — Energy

Riboflavin is essential to the process by which the body produces energy. Also essential for dealing with the toxic products of cell energy production — free radicals. Deficiency can come from an unbalanced diet. People who exercise heavily may need more, particularily women.

Recommended Daily Allowances

  • Adult men & women 1.2 - 1.8 mg daily
  • Adults who exercise vigorously 2 - 2.5 mg daily
  • Pregnant and nursing women 1.6 - 1.8 mg daily
  • Supplementation of 1.7-10 mg should be considered for: alcoholics, people eating unbalanced diets — especially the elderly, and those taking certain medications (speak to your doctor)


High doses appear to have no adverse effects

Niacin (B3) — Cholesterol buster

There are two forms of niacin, nicotinic acid and nicotinamide, but the name niacin is commonly used to refer to both of them. Niacin has been shown to lower cholesterol and to significantly reduce the risk of death in people who have had a heart attack. In addition niacin is involved in a great many other body processes and has been suggested to be useful as a detoxifying agent and even to aid in preventing schizophrenia.

Recommended Daily Allowances

  • Adults 13-19 mg daily
  • Infants 5-6 mg daily
  • Children (1-10) 9-13 mg daily


Large doses should only be considered on the advice of your physician and may cause side effects

Pantothenic Acid (B5) - Energy

Panthothenic acid is involved in manufacturing two crucial enzymes which act in the body's ability to turn fats and carbohydrates into energy. It is also essential for the production of a number of hormones and for making red blood cells. There have been many wonderful effects that have been claimed for pantothenic acid such as boosting energy, lowering cholesterol, preventing heart disease, preventing arthritis, speeding wound healing and preventing many of the signs of aging — to name just a few. The evidence for most of these is not convincing, but we?d love to be proved wrong by future research.

There is no RDA for pantothenic acid, but a good level of intake is 4 - 7 mg per day for adults.

High doses appear to have no adverse effects

Pyridoxine (B6) - Boosts immunity and lowers heart disease

Pydidoxine is necessary for the multiplication of all cells and so is very important for the production of red blood cells and the cells of the immune system. Pyridoxine also acts to help prevent heart disease by helping to break down homocysteine. It is necessary for the proper function of many enzymes. Of all the B vitamins, pyridoxine is the one that is most important for the immune system.

Recommended Daily Allowances 2 mg per day for adults

Warning: pyridoxine is toxic in high doses and can cause nerve damage, do not take more than 50 mg per day.

Biotin (B7) — Not much of a problem

Biotin can be obtained from your diet, but the bacteria which live in our intestines do a great job of making more than enough and consequently it?s very rare for anyone to have a deficiency. Biotin is necessary for you to properly use the amino acids and fats in your diet. Deficiencies can lead to hair loss and this has led to claims that biotin does all kinds of wonderful things for your hair and prevents hair loss. Consequently, some shampoos and conditioners contain biotin, but biotin will certainly not prevent hair loss.

Because the friendly bacteria in our intestines produce more biotin than we need, there is no recommended daily allowance for biotin.

Folic Acid (B9) — Heart smart

The main role of folic acid in the body is in the production of DNA for new cells. This is especially important for the cells which turn over rapidly in the body such as red blood cells, skin cells and the cells that line the intestines. Not only that, but folic acid has been shown to do some other pretty amazing things such as helping to prevent heart disease, helping to prevent birth defects and maybe even preventing cancer. Certain groups of people may be deficient in folic acid, especially if you are pregnant, breast-feeding, abuse alcohol, or smoke.

The RDA for folic acid is about 200 micrograms for adult men and women, and 50-150 micrograms for children. Women of childbearing age should get 400 micrograms a day to help ensure against birth defects.

Warning: In large doses folic acid can be toxic and cause neurologic problems.

Many dieticians, researchers and doctors believe that these recommendations are too low and that they can be safely doubled.

Cobalamin (B12) - Healthy blood

Cobalamin is necessary for healthy nerve tissue and especially red blood cells. It has also been suggested to have anti-cancer properties and to work wonders upon mental conditions. Deficiency can lead to nervous disorders and anemia. Cobalamin is found naturally only in animal tissue and so vegetarians are prone to a risk of deficiency and should seriously consider a supplement containing an adequate amount. The elderly are also prone to deficiencies.

Recommended Daily Allowances

  • Adults 2 micrograms per day
  • Children 1-2 micrograms


High doses appear to have no adverse effects

Getting enough Bs? Do you need a supplement?
B vitamins are easy to find, they are present in a wide variety of foods and most people get more than the RDA from their normal diet.

Good general food sources of B vitamins include: meat, chicken, fish, dairy products, beans, nuts and green leafy vegetables.

In general, there are a few groups of people that can be prone to deficiencies:

The elderly
As the body ages we become less able to absorb the B vitamins. If you are over 55 you should talk to your physician about whether taking a B vitamin supplement is appropriate for you.

Alcohol abusers
Alcohol interferes with the body?s ability to absorb vitamin Bs, and so alcohol abusers may suffer from deficiencies.

Vegetarians
Animal products are a good source of most vitamin Bs and so vegetarians should be careful to ensure they get enough B vitamins from other sources.

Smokers
Smoking decreases your body?s ability to absorb the Bs.

People with chronic digestive problems
These conditions may mean people can have trouble absorbing enough of the Bs from their diet through their intestines.

Should you need a supplement you should consider one which has a balance of the B vitamins, since if you are low on one, the chances are you are not getting enough of the others.

Summary
B vitamins are involved in an enormous number of essential processes in the body. They are all necessary for healthy living and if you are deficient in one, the chances are your not getting enough of all of them. However, the good news is that for most of us a healthy diet will provide adequate amounts of all of the Bs. The benefits they can bring include preventing heart disease, keeping your immune system in good shape and making sure you can produce the energy your body needs.

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