Folate
Folate, also known as vitamin B9 and folacin,[6] is one of the B vitamins.[3] Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and storage.[7] Folate is required for the body to make DNA and RNA and metabolise amino acids necessary for cell division and maturation of blood cells.[1][8] As the human body cannot make folate, it is required in the diet, making it an essential nutrient.[9] It occurs naturally in many foods.[6][1] The recommended adult daily intake of folate in the U.S. is 400 micrograms from foods or dietary supplements.[1]
Clinical data
Folicet, Folvite
- US DailyMed: Folic acid
- AU: A
50–100%[3]
Urine[3]
- DB00158
- as salt: DBSALT001918
- 935E97BOY8
- as salt: 9P9W8GGU78
C19H19N7O6
441.404 g·mol−1
1.6±0.1 g/cm3 [5]
250 °C (482 °F) (decomposition)
1.6mg/L (25 °C)
Folate in the form of folic acid is used to treat anemia caused by folate deficiency.[3] Folic acid is also used as a supplement by women during pregnancy to reduce the risk of neural tube defects (NTDs) in the baby.[3][10] Low levels in early pregnancy are believed to be the cause of more than half of babies born with NTDs.[1] More than 80 countries use either mandatory or voluntary fortification of certain foods with folic acid as a measure to decrease the rate of NTDs.[11] Long-term supplementation with relatively large amounts of folic acid is associated with a small reduction in the risk of stroke[12] and an increased risk of prostate cancer.[13] There are concerns that large amounts of supplemental folic acid can hide vitamin B12 deficiency.[1]
Not consuming enough folate can lead to folate deficiency.[1] This may result in a type of anemia in which red blood cells become abnormally large.[1] Symptoms may include feeling tired, heart palpitations, shortness of breath, open sores on the tongue, and changes in the color of the skin or hair.[1] Folate deficiency in children may develop within a month of poor dietary intake.[14] In adults, normal total body folate is between 10 and 30 mg with about half of this amount stored in the liver and the remainder in blood and body tissues.[1] In plasma, the natural folate range is 150 to 450 nM.[15]
Folate was discovered between 1931 and 1943.[16] It is on the World Health Organization's List of Essential Medicines.[17] In 2021, it was the 77th most commonly prescribed medication in the United States, with more than 8 million prescriptions.[18][19] The term "folic" is from the Latin word folium (which means leaf) because it was found in dark-green leafy vegetables.[20]
Drug interference[edit]
A number of drugs interfere with the biosynthesis of THF from folic acid. Among them are the antifolate dihydrofolate reductase inhibitors such as the antimicrobial, trimethoprim, the antiprotozoal, pyrimethamine and the chemotherapy drug methotrexate,[88][89] and the sulfonamides (competitive inhibitors of 4-aminobenzoic acid in the reactions of dihydropteroate synthetase).[90]
Valproic acid, one of the most commonly prescribed epilepsy treatment drugs, also used to treat certain psychological conditions such as bipolar disorder, is a known inhibitor of folic acid, and as such, has been shown to cause birth defects, including neural tube defects, plus increased risk for children having cognitive impairment and autism. There is evidence that folate consumption is protective.[91][92][93]
Folate deficiency is common in alcoholics, attributed to both inadequate diet and an inhibition in intestinal processing of the vitamin. Chronic alcohol use inhibits both the digestion process of dietary folate polyglutamates and the uptake phase of liberated folate monoglutamates. The latter is associated with a significant reduction in the level of
expression of RFC.[78]
Animals[edit]
Veterinarians may test cats and dogs if a risk of folate deficiency is indicated. Cats with exocrine pancreatic insufficiency, more so than dogs, may have low serum folate. In dog breeds at risk for cleft lip and cleft palate dietary folic acid supplementation significantly decreased incidence.[149]
Current versions from the International Union of Biochemistry and Molecular Biology's Recommendations on Biochemical & Organic Nomenclature, Symbols & Terminology etc. Enzyme Nomenclature, Miscellaneous Reaction Schemes section Pterins, Riboflavins, etc. formerly hosted by Queen Mary College (all archived by archive.org):