Role Of B Complex Vitamins

B-complex vitamins are a family of nutrients containing the B vitamins. These B vitamins are B-1, B-2, B-3, B-5, B-6, B-7, B-9, and B-12. Each of these vitamins plays an important role in maintaining functions inside the cell. Some B vitamins have been shown to possess a number of important physiological properties. The significance of the B vitamins in the body can be illustrated when a person's level of a particular B vitamin is too high or low. This can cause any number of physiological dysfunctions of varying severity.

Effects on the Fetus

Vitamin B-9, commonly called folic acid, is an essential chemical for preventing birth defects, says the National Institutes of Health, or NIH. It is needed during embryonic development of the central nervous system because it orchestrates normal formation of neuronal structures. If a pregnant mother has a folic acid deficiency, then her baby can be born with the birth defects called anencephaly or spina bifida. These are malformations where the baby's brain or spinal cord, respectively grow partially or totally outside of its skull or spinal column. The consequence may be severe neurological impairment or even death of the baby.

Nervous System Function

The nervous system requires B vitamins to operate normally. The NIH says vitamin B-6, commonly called pyridoxine, may have an effect on the formation of headaches, seizure, some forms of depression and Parkinson's disease. It is a key ingredient in the chemical synthesis of serotonin and dopamine, two neurotransmitters needed for brain cells to communicate. Vitamin B-12, commonly called methylcobalamin, helps avoid neurological problems and can aid in recovering some consequences of Bell's palsy. If a diet contains insufficient levels of vitamin B-12 the result can be neurological impairment such as spasticity in the limbs, walking difficulty, and bowel or bladder problems. Vitamin B-1, commonly called thiamine, can help with the brain's cognitive abilities.

Maintaining Blood Glucose

A crucial function of vitamin B-6 is maintaining blood glucose within normal range throughout the day. Steady blood glucose levels are important for maintaining energy. As the body's calorie intake begins to fall, vitamin B-6 is needed to turn stored nutrients and carbohydrates into glucose so that blood glucose levels remain stable. A diet without sufficient vitamin B-6 levels can hinder the body's capability to maintain normal blood glucose levels during the day and during periods of stress. The NIH says taking vitamin B-6 supplements do not improve this ability if the person is already healthy and well-nourished.

Other Functions

The American Cancer Society has concluded that when the recommended dietary amount of vitamin B-9 is taken, it can significantly reduce the risk of cancer. Vitamin B-6 is a key ingredient in the metabolism of some enzymes and proteins, says the NIH. Vitamin B-12 and vitamin B-5, commonly called pantothenic acid, help to fight anemia. Vitamin B-5 aids the body in maintaining normal immune and gastrointestinal function. Vitamins B-12 and B-2, commonly called riboflavin, are key factors in making erythrocytes, or red blood cells. Normal blood circulation is maintained with the help of vitamin B-1.

Recommended Dietary Allowance

The U.S. Department of Agriculture lists the RDA for the B-vitamins. In pregnant women, 600 mcg of vitamin B-9 is recommended. In all adults, 2.4 mcg of vitamin B-12 is recommended. In adults 19 to 50 years old, 1.3 mg of vitamin B-6 is recommended; in adults over 50, 1.5 mg to 1.7 mg is recommended. In all adults, 1 mg to 1.2 mg of vitamin B-1 is recommended. In all adults, 1.1 mg to 1.3 mg of vitamin B-2 is recommended. In all adults, 5 mg to 10 mg of vitamin B-5 is recommended.