The B-complex vitamins are water-soluble, meaning the body does not store them, and they function in various roles of the metabolic process. The eight B vitamins help the body convert food into fuel to produce energy and play a role in metabolizing fats and protein, and neurotransmitter production, and are vital to the proper functioning of the nervous system. Four of the B vitamins play a key role in energy production: thiamin, riboflavin, niacin and B-6.
Thiamin, or vitamin B-1, functions in the body as a coenzyme for energy production. A coenzyme is a helper molecule for biological functions. Thiamin plays a role in breaking down carbohydrates and amino acids for energy. It is vital for maintaining proper function of the gastrointestinal, nervous and cardiovascular systems. Thiamin deficiencies can cause weakness, fatigue, psychosis and nerve damage.
Riboflavin functions as a vital coenzyme in energy production and tissue-protein building, making it essential to tissue growth and health. It plays a key role in the metabolism of fats, proteins and carbohydrates. Deficiencies of riboflavin are rare because it is abundant in food sources. Severe deficiencies lead to sore throat, mouth lesions, inflammation of the tongue, skin disorders, anemia and peripheral nerve disorder.
Niacin partners with riboflavin in the metabolic systems that produce energy, and also is involved in DNA and calcium mobilization in the body. Other key roles of niacin are in fatty acid synthesis, cholesterol and steroid hormone synthesis. Deficiency of niacin results in a condition known as pellagra. Pellagra is characterized by dermatitis, dementia, diarrhea, weakness, vertigo and, in severe cases, death. Niacin deficiency is rare in developed countries and usually is the result of alcohol abuse.
Vitamin B6, also known as pyroxidine, is stored in tissues throughout the body and plays a role in amino acid absorption, energy production, red blood cell formation and niacin formation. It also is active in the breakdown of carbohydrates and fat.
Thiamin, riboflavin, niacin and B6 all play a role in energy production. As water-soluble vitamins, they are excreted by the body through the urine when they are not used. However, all four also can be toxic when consumed in large quantities. Consult your physician on the recommended amounts of each vitamin prior to starting a regimen.