The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. Historically, the B vitamins were once thought to be a single vitamin, referred to as Vitamin B (much like how people refer to Vitamin C or Vitamin D). Later research showed that they are chemically distinct vitamins that often coexist in the same foods.Supplements containing all eight B vitamins are generally referred to as a vitamin B complex. Individual B vitamin supplements are referred to by the specific name of each vitamin (eg B1, B2, B3).The B vitamins often work together to deliver a number of health benefits to the body. B vitamins have been shown to: support and increase the rate of metabolism; maintain healthy skin and muscle tone; enhance immune and nervous system function; promote cell growth and division - including that of the red blood cells that help prevent anemia. Together, they also help combat the symptoms and causes of stress, depression, and cardiovascular disease. All B vitamins are water soluble, and are dispersed throughout the body. They must be replenished daily with any excess excreted in the urine. Vitamin B deficiency can lead to an enormous group of health problems. This book presents new and important research in the field.