FOLATE & VITAMIN B12 BIOMARKERS
Folate is a B group vitamin that is essential for healthy growth and development. Folate is found naturally in food, such as green leafy vegetables, fruits and grains, while folic acid is the synthetic form of folate added to food or used in dietary supplements.1 Folate can help prevent neural tube defects in babies, such as spina bifida, if it is taken before conception and early in pregnancy. Currently in Australia, all wheat flour (except organic flour) is fortified with folic acid as part of the mandatory folic acid fortification standard.
In the National Health Measures Survey (NHMS), folate biomarkers included serum folate and Red Cell Folate (RCF), and these folate levels were measured via a blood test. Research suggests that serum folate and RCF levels should be measured in conjunction with each other as the serum folate test measures recent folate intake and the RCF test measures longer term folate stores due to the life span (120 days) of the red cell.2
National Folate Guidelines
Data on folate levels has been collected to provide national estimates to report on the effectiveness of the mandatory folic acid fortification standard developed by Food Standards Australia New Zealand (FSANZ).3 The current recommendations of folic acid intake for women of child bearing age (16 to 44 years) is 400 μg per day before conception and during the early months of pregnancy.2 In addition to reporting folate levels for women of child bearing age, the NHMS objectively measures the folate levels of all Australians aged 12 years and over.
Vitamin B12 is a water-soluble vitamin with a key role in the normal functioning of the brain and nervous system, and for the formation of blood. Vitamin B12 is a nutrient that helps keep the body's nerve and blood cells healthy and helps make DNA. Vitamin B12 is vital for the formation of red blood cells, as well as for the proper functioning and health of nerve tissue. If left untreated, vitamin B12 deficiency, can lead to anemia, as well as nerve and brain damage. Vitamin B12 is also important for folate levels, as low levels of vitamin B12 can interfere with the body's ability to use folate.1
In the NHMS, folate and vitamin B12 levels were measured for participants aged 12 years and over, who agreed to participate in the NHMS and provided a blood sample.
More information regarding the biomedical tests and cut off points can be found in the relevant subsections.
1 Gibson RS 2005, Principles of Nutritional Assessment, 2nd ed, New York: Oxford University Press.
2 Heil W and V Ehrhardt 2008, Reference Ranges for Adults and Children: Pre-Analytical Considerations, Roche Diagnostics GmbH, Mannheim, <https://www.rochediagnostics.fr/Htdocs/media/pdf/actualites/2a_Reference_Ranges_2008.pdf>, Last accessed 07/11/2013.
3 AIHW 2011, Mandatory folic acid and iodine fortification in Australia and New Zealand: baseline report for monitoring, <http://www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=10737418918&libID=10737418917>, Last accessed 13/11/2013.