Vitamin B9 Functions, Sources, Deficiency Symptoms, Dose

Vitamin B9, also referred to as folic acid or folate, is one of the most essential vitamins belonging to the class of B complex vitamins. This vitamin is probably best known for its importance in pregnancy and fetal development.

Functions of Vitamin B9

vitamin B9Folic acid is necessary for optimal brain functioning and has an important role in the production of RNA and DNA. It plays an important role in the development of the brain of the fetus during pregnancy. Pregnant mothers are given supplemental doses of folic acid so that there is appropriate development of the fetus and also to prevent neural tube defects (birth defects). Folic acid is also essential for the rapid growth of the cells during pregnancy, infancy and adolescence.



Vitamin B9 works in conjunction with other vitamins such as vitamin B12 for the production of RBCs, and maintains the functioning of iron in the body. It also works with vitamin B6 and B12 to control the serum levels of homocysteine, an essential amino acid. Therefore, vitamin B9 has also been found to be important in maintaining the functioning of the heart as it controls the level of homocysteine. Increase in the level of homocysteine in the blood indicates heart dysfunctioning.

Food Sources of Vitamin B9

Rich sources of vitamin B9 include:

  • dark green leafy vegetables such as spinach
  • asparagus
  • fenugreek leaves
  • sprouts
  • mustard greens
  • turnips
  • beetroots
  • soya beans

Other sources are:

  • beef liver
  • yeast
  • salmon
  • whole grains
  • root vegetables
  • wheat
  • kidney beans
  • whole pulses
  • lima beans
  • avocado
  • orange juice and milk

Symptoms of Vitamin B9 Deficiency

Folic acid deficiency occurs when the newborn baby does not receive enough of this vitamin in the womb. A fetus that has received insufficient quantities of folic acid has strong possibilities of being born with spina bifida and may also suffer from serious defects of the nervous system.

Deficiency of folic acid may also lead to the following:

  • occurrence of acne
  • cracked lips
  • cracking on the corners of the mouth
  • sore tongue
  • feeling of tiredness
  • nausea

Deficiency for a long period of time would lead to the following:

  • osteoporosis
  • anemia
  • chronic fatigue syndrome
  • high blood pressure
  • Alzheimer’s disease
  • cancer of the cervix, rectum and bowel

Folic acid has many roles to play in the development of bones and iron uptake by the cells. Hence its deficiency may lead to malfunctioning of the vital systems.

Dosage of Vitamin B9 Supplements

Dietary sources available for folic acid should be sufficient for all individuals except pregnant women as they need extra supplementation during the first trimester of pregnancy. The adequate intake for infants and RDA for children and adults is as follows. It needs to be understood here that for infants the vitamin requirements and/or any other nutrient requirements is met through breast milk, but if the child is not breastfed due to some reason then supplementation may be required.

Infants

  • 0 – 6 months: 65mcg / day (reads as 65 microgram per day)
  • 7 – 12 months: 80mcg/day

Children

  • 1 – 3 years: 150mcg/day
  • 4 – 8 years: 200mcg/day
  • 9 – 13 years: 300mcg/day
  • 14 – 18 years: 400mcg/day

Adults

  • 19 years and above: 400mcg/day
  • Pregnant women: 600 mcg/day
  • Lactating mothers: 500mcg/day