B vitamins

The B vitamin complex (also called B vitamins) are a group of 8 vitamins. They have an important job in the metabolism of cells. Each B vitamin is a cofactor (a coenzyme) for some key metabolic processes or it is a precursor needed to make one. B vitamins are water-soluble and are stored in the water in the body, and excreted in urine.

Originally, people thought they were just different forms of one vitamin (as with Vitamin D, for example). Later it turned out that they are separate vitamins that often can be found together. The B vitamins that the body cannot make are:

• Thiamine (Vitamin B₁)
• Riboflavin (Vitamin B₂)
• Niacin (Vitamin B₃), also called Vitamin PP (Pellagra Preventive)
• Pantothenic acid (Vitamin B₅)
• Pyridoxine (Vitamin B₆)
• Biotin (Vitamin B₇), also called Vitamin H

Vitamin P is now known as flavonoids. Vitamin B₄, called adenine, thought to be a vitamin in the past, or associated with choline in the past, is no longer classified as a vitamin because the body can make (synthesize) it. Vitamin B₈ (inositol) is now referred to as a vitamin-like sugar alcohol. Inositol is used in nerve functioning, nutrient metabolism, as well as insulin signalling.

B vitamins are required for growth, and proper functioning of nerves and muscles. B vitamins are found in meat, milk, whole grains and fresh vegetables.

Deficiency

Vitamin B deficiencies have been shown to cause symptoms like:

• mental health problems
  • Someone with a deficiency in B vitamins might have paranoia, "vague fear", fear that something dreadful (bad) is about to happen, ADD (attention deficiency), inability to concentrate, or feeling nervous
  • crying spells, inability to cope
• thoughts of dying
• heart palpitations (heart arrhythmias)
• exhaustion (being tired)
• frustration
• inability to sleep
• restlessness
• tingling in hands, fingers, toes (paresthesia)
• soreness all over

Well-known medical syndromes caused by thiamine deficiency are beri-beri, Wernicke–Korsakoff syndrome (WKS), and optic neuropathy.

Related pages

• Vitamin A (retinol) and C (ascorbic acid)