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What Are the Benefits of B-Complex Vitamins?

author image Christian Walker, Ph.D.
What Are the Benefits of B-Complex Vitamins?
B-complex vitamins are crucial for health. Photo Credit: Miha Peroša/iStock/Getty Images

B-complex vitamin capsules contain vitamins B1, B2, B3, B5, B6, B7, B9 and B12. Each B vitamin has an important physiological role in the body. If a person lacks a particular B vitamin, or takes excessive amounts, the consequences can have serious harmful effects on the body. Both physiological and psychological problems can result.

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Fetal Health

The chemical known as vitamin B9, or folic acid, is crucial for development of the fetal central nervous system. Vitamin B9 is necessary to allow the fetus’s brain and spinal cord to grow into their normal shape. If the mother lacks folic acid in her diet, the fetus can develop certain birth defects known as anencephaly and spina bifida. These are malformations where the brain and spinal cord, respectively, develop and grow, partially or totally, on the outside of the skull or spinal column. The fetus can suffer severe neurological impairment or death as a result.

Nervous System

B-vitamins are required for the adult nervous system to function properly. Vitamin B6, also called pyridoxine, may help prevent Parkinson’s disease, seizures, depression, headaches and other neurological problems. It is also required to manufacture the brain chemicals dopamine and serotonin, necessary for communication between brain cells. Other neurological problems can be prevented with vitamin B12, also called methylcobalamin, such as aiding the recovery of Bell’s palsy. A dietary deficiency of vitamin B12 can lead to marked neurological impairment such as walking disability, spasticity in the legs and arms and problems with the bowels and bladder. Vitamin B1, also called thiamine, is necessary for normal cognitive function in the brain.

Blood Glucose

The body must maintain relatively even levels of blood glucose throughout the day in order to keep energy levels constant. This is one important function of vitamin B6. As calorie intake begins to fall, vitamin B6 is needed to convert carbohydrates and nutrients stored by the body into glucose so that normal levels are maintained. When a diet is vitamin B6 deficient, the ability to maintain normal glucose levels is hindered. If a person is already well-nourished vitamin B6 supplements will not improve the ability to regulate blood glucose.

Other Functions

Recent studies have shown that if the recommended dietary amounts of vitamin B9 are taken, the risk of cancer is reduced, according to the American Cancer Society. Vitamin B6 is a necessary component for metabolizing certain enzymes and proteins. Vitamin B12 and vitamin B5, also called pantothenic acid, are needed to help the body from developing anemia. The immune and gastrointestinal systems require vitamin B5 for helping to maintain their normal function. Vitamins B12 and B2, also called riboflavin are an important component during the manufacture of red blood cells. The body’s ability to effectively circulate blood is improved with vitamin B1.

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