The vitamin B complex is a collection of eight essential vitamins found in food. These are the vitamins thiamine, riboflavin, niacin, vitamin B6, folate, vitamin B12, pantothenic acid, and biotin. The B complex vitamins are essential for many metabolic processes in the body, including energy production, cellular metabolism, and cell growth. The B complex vitamins are also important in many other body functions such as the prevention of birth defects, vision and bone health.