The B vitamin family is rather large. B-complex vitamins include B-1,B-2, B-3, B-5, B-6, B-7, B-9 and B-12. The fact that they are water-soluble means they should be replenished regularly as any excess of these vitamins are excreted in urine. Food sources of B vitamins include beef liver, red meat, fish, poultry, brewer's yeast, fortified breads and cereals and green leafy vegetables. The body needs B vitamins for various functions.
You want to know that your metabolism is working properly, and this is where B vitamins come in. B-complex vitamins all work together to support cellular metabolism. B vitamins help the body metabolize carbohydrates, proteins and fats into glucose, which the body uses for energy. Glucose is the main source of energy for the brain and the body. Lack of B vitamins leads to weakness and fatigue.
The B vitamins help maintain healthy nerve cells and proper neurological functioning. Insufficient B vitamin intake can lead to neurological symptoms such numbness and tingling of arms and legs, difficulty walking, confusion, memory loss, depression, psychosis and dementia. Pregnant women who are deficient in folic acid, or vitamin B-9, are more likely to have children with neural tube defects. Folic acid is necessary for proper cell division of nerve cells, and lack of folic acid may lead to abnormal development of the neural tube.
Red Blood Cell Production
Vitamin B-9 or folic acid also works closely with vitamin B-12, also called cobalamin, to help the bone marrow produce healthy red blood cells. B-12 and folic acid is also important for the production of DNA, the body's genetic material. Lack of enough folic acid leads to folic acid deficiency anemia and deficiency in B-12 causes pernicious anemia.
Control of Homocysteine Levels
Vitamin B-6, B-12 and folic acid work together to control blood levels of homocysteine -- an amino acid produced from the break down of protein-rich foods. High levels of homocysteine can cause chronic conditions, such as heart disease, Alzheimer's and depression, according to the University of Maryland Medical Center.