Vitamin B9

The terms vitamin B9, folic acid and folate are often used interchangeably. While folates are found in foods as well as in metabolically active forms in the human body (1), folic acid, the more stable form, occurs rarely in nature but is the form most often used in vitamin supplements and fortified foods.

Health functions

The only function of vitamin B9 (folate) coenzymes in the body appears to be acting as acceptors and donors of one-carbon units (e.g., methyl, -CH3, and methylene, -CH2-) in a variety of reactions critical to the metabolism of nucleic acids and amino acids (2, 3).

Disease risk reduction

Neural tube defects (NTD) cause crippling birth defects, which are sometimes fatal. They come about between the 21st and 27th days of the embryo’s development when a lot of women do not even know they are pregnant (5).

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Things to know about Vitamin B9

  • Other Applications

    Some studies show that 15–38% of people with depression have low vitamin B9 (folate) levels in their bodies, and those with very low levels tend to be the most depressed.

  • Intake Recommendations

    To set the new dietary recommendation for vitamin B9 (folate), the ‘Dietary Folate Equivalent’ (DFE) has been used, reflecting the higher bioavailability of synthetic folic acid found in supplements and fortified foods compared to that of naturally occurring food folates (35).

  • Supply Situation

    In most European countries, the average vitamin B9 (folate) intake does not meet national recommendations.

  • Deficiency

    Individuals in the early stages of folate deficiency may not show obvious symptoms, but blood levels of homocysteine may increase.

  • Sources

    Cooked spinach, asparagus, and lentils, as well as citrus fruit juices are rich sources of vitamin B9 (folate) (1).

  • Safety

    No adverse effects have been associated with the consumption of excess vitamin B9 (folate) from foods. Concerns regarding safety are limited to synthetic folic acid intake.

  • References

    Consult the full list of scientific references.