Vitamin B8 Functions, Sources, Deficiency Symptoms, Dose

Vitamin B8, also known as inositol, is a water-soluble vitamin that is required in very small amounts in the body. As it is a water-soluble vitamin, it is not stored in the body and excess amounts of it is flushed out with urine. Hence, it becomes all the more important for us to ensure that our diet supplies adequate amount of this vitamin daily. Followed by niacin, our body has the second highest store of inositol.

Functions of Vitamin B8

nutsVitamin B8 has many important functions to its credit. It is required for the metabolism of carbohydrates, fats and proteins for the production of glucose. It is involved in the uptake and utilization of glucose by the cells.



Inositol is required for maintaining a healthy immune system, thereby protecting the body against infection. Various research and clinical trials have suggested that inositol is necessary for the normal growth and survival of the human body. Inositol is very important for the appropriate functioning of the nervous system.

Its supplementation provides relief to patients suffering from multiple sclerosis. It plays an active role in maintaining the healthy functioning of the nervous system in diabetic individuals. Hence, it provides relief to diabetic nephropathy patients suffering from pain and numbness in the hands and legs. It acts as a mild lipotropic agent which helps with the loss of extra fat in overweight and obese individuals.

Food Sources of Vitamin B8

Inositol is available externally through dietary sources and is even made inside the body by intestinal bacteria. Our body can make its own inositol from glucose with the help of intestinal bacteria. Hence, external sources are of help only in conditions when the body is incapable of making its own vitamin. Sources of vitamin B8 consist of the following:

  • nuts
  • oilseeds
  • whole grains
  • egg yolk
  • legumes
  • banana
  • yeast
  • mushroom
  • sardines
  • cauliflower
  • swiss chard

Other sources include the following:

  • lecithin
  • liver
  • wheat germ
  • raisins
  • peanuts
  • cabbage
  • all citrus fruits except lemons
  • cantaloupe
  • lima beans

Symptoms of Vitamin B8 Deficiency

Deficiency of vitamin B8 is unlikely. However, a word of caution for coffee lovers—they need to restrict their daily intake to 2 cups as excessive coffee can deplete the vitamin stores. The symptoms resulting from a deficiency of vitamin B8 include:

  • skin diseases
  • reduced production of RNA and DNA
  • insufficient synthesis of glucose from the food digested
  • decreased functioning of hormones
  • onset of candida albicans

Other symptoms include nausea, vomiting, muscle ache, lethargy, hallucinations, depression, irritability, confusion, drowsiness, muscle weakness, lung infections, heart abnormalities, elevated levels of cholesterol, constipation, vision problems, dermatitis, hair loss, eczema and ataxia.

Various serious complications of vitamin B8 deficiency include metabolic acidosis, organic aciduria, liver steatosis, convulsions, hyper ammonemia, acidocetosis, hypotonia and hyperlactettemia. If vitamin B8 deficiency is not arrested in time and the symptoms are not controlled, one may even go into coma.

Dosage of Vitamin B8 Supplements

The daily intake of vitamin B8 for infants, children, adults, pregnant and lactating women is as follows:

Infants

  • 0 – 12 months: 35mcg/day/kg body weight

Children

  • 1 – 3 years: 50mcg/day
  • 4 – 8 years: 50 – 100mcg/day
  • 9 – 13 years: 100 – 150mcg/day

Adolescents and Adults

  • For males and females aged 14 years and above: 150 – 200 mcg/day
  • For pregnant women: 100 – 150mcg/day
  • For lactating women: 150 – 200mcg/day