The B Vitamins Reviewed - Part 1

B Vitamins are needed for the proper functioning of almost every process in the body. Here's a review of the first four B vitamins:


The B Vitamins

• B1 - Thiamin
• B2 - Riboflavin
• B3 - Niacin
• Biotin
• B5 - Pantothenic Acid
• Folate
• B6 - Pyridoxine
• B12 - Cobalamin

The best way to avoid a deficiency of B vitamins is to eat a varied diet of fresh fruit, an abundance of vegetables, whole grains, legumes, nuts and seeds, and other food as desired. Some of these B vitamins can also be made by friendly bacteria in a healthy colon and absorbed into circulation.


The Roles of B vitamins

• The primary role of the B vitamins is catalyzing energy production in the body.

• The B vitamins are needed for healthy nerve conduction and thus muscle action.

• They are needed for the synthesis of many important neurotransmitters, such as acetylcholine, serotonin, dopamine, and norepinephrine.

• The B vitamins are well known for helping with stress. 

• B vitamins help with our metabolism by helping to convert fats and amino acids to glucose (blood sugar).

• B vitamins are needed to build hemoglobin, which carries oxygen throughout the body.

• B vitamins help us convert the amino acids that make up protein.

• The vitamin B complex is vital for the synthesis of fatty acids.

• The B vitamins help us make cholesterol and also help us control cholesterol.

• They are needed to synthesize steroid hormones such as melatonin, the sleep hormone.

• Some of the B vitamins are useful in protcting us from free radical attack.

• B vitamins can lower homocysteine levels to reduce our risk of heart disease.

• They work with important antioxidants such as glutathione. Also, B vitamins help us eliminate certain drugs, carcinogens, and steroid hormones.

B1 - Thiamin
Thiamin is found in rice bran and rice germ, both of which are removed when white rice  is made from brown rice. Lack of thiamin in white rice causes beriberi. Thiamin plays a key role in the metabolism of energy in all cells.
The amount of dietary thiamin needed is based on the amount needed in producing energy. Thiamin needs will be met by most normal diets if enough food is eaten to meet energy requirements.


Thiamin deficiency can result from inadequate food intake. Thiamin deficiency is common among alcoholics, who often have inadequate food intakes. Alcohol provides energy without providing many of the necessary nutrients. Alcohol also impairs the absorption of thiamin, while increasing excretion of thiamin.


RDAs for the B vitamins are bold and the Adequate Daily Intakes are not bold.

B2 - Riboflavin
Riboflavin has a greenish-yellow color, which led to one of its early names, vitamin G.
Flavins derived from riboflavin play a vital role in the metabolism and elimination of toxins, drugs, carcinogens, and steroid hormones.  Riboflavin deficiency is associated with the increased oxidative stress that can be caused by free radicals. A deficiency of riboflavin will reduce the efficiency of glutathione, an important antioxidant.
The best sources for riboflavin are whole grains and green leafy vegetables; spinach, broccoli, chard, and asparagus are all rich sources of riboflavin. Almonds and soybeans are good sources. Dairy products have large amounts of riboflavin. Nutritional yeast is high in riboflavin and many other nutrients. The RDA for men is 1.3 mg per day and for women, 1.1 mg. Riboflavin is not toxic.

B3 - Niacin
Vitamin B3 can be found in two different forms, niacin and niacinamide. Niacin is known chemically as nicotinic acid and can cause skin flushing if taken in larger doses. Niacinamide is the form of niacin commonly found in the blood and is known chemically as nicotinamide. Nicotinic acid can easily be converted into nicotinamide in the body. By the way, there is no chemical relationship to the nicotine in tobacco. Iron and an essential amino acid, tryptophan, are both needed to synthesize niacin.
When a severe deficiency of niacin occurs, the deficiency disease is called pellagra. Pellagra is characterized by the four Ds: diarrhea, dermatitis, dementia, and death.
Nicotinic acid has been used to lower blood cholesterol in large doses of 3000 mg or more per day. This has resulted in a lowering of the bad LDL (low density lipoprotein) cholesterol and also raises the good HDL (high density lipoprotein) cholesterol.
The average diet supplies an adequate amount of niacin. Niacin is not stored in the body. Cooked whole grains, legumes, and seeds are preferred sources of niacin; enriched grains, mushrooms, leafy green vegetables, and nutritional yeast are other good sources. Pork, beef, chicken, fish, and dairy products are very high in niacin, but are also high in cholesterol. Niacin is somewhat heat-resistant and is not depleted with normal cooking. Niacin may, however, be leached into cooking water.
The RDA for niacin is 16 mg for men and 14 mg for women. For the nicotinic acid form of niacin, the upper limit to avoid flushing is 35 mg per day.

Biotin
Biotin was originally referred to as vitamin H. Deficiency of biotin has been noted in prolonged intravenous feeding where biotin was omitted. The only other example of biotin deficiency is from long-term consumption of raw egg whites. Biotin can bind to avadin, a protein found in egg whites. Cooking inactivates this bond, so cooked egg whites do not bind biotin. Biotin is made by the bacteria living in healthy large intestines. The wall of the large intestine has a specialized process for the uptake of biotin. This may be one reason why biotin deficiency is so rare. The RDA for biotin is 30 mcg both for men and for women.

Go To B Vitamins Reviewed - Part 2

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