Folate is a B vitamin that is important in cell growth and reproduction. This page provides information about folate, and New Zealand’s policy on folic acid supplementation for reducing neural tube defects.
Questions and answers
On this page:
- What is folate/folic acid?
- Why do we need folate?
- How much folate is recommended?
- Why do we need folic acid?
- What is a neural tube defect (NTD)?
- How common are neural tube defects in New Zealand?
- What is the current policy on folic acid supplementation for reducing NTDs?
- Can we increase folate intake?
- Why do women planning a pregnancy need to take a folic acid supplement?
- Are there any adverse effects to taking the recommended folic acid tablet?
- What do other countries do?
What is folate/folic acid?
Folate is an essential B vitamin and is found naturally in leafy vegetables, citrus fruits, wholemeal bread, yeast, liver and legumes.
Folic acid refers to pteroylmonoglutamic acid and is the synthetic (‘man made’) form of folate. Folic acid is used in dietary supplements and fortified foods and beverages. It is more bio-available (more readily absorbed and used in the body) and stable, than naturally occurring food folate.
Why do we need folate?
Folate is important in cell growth and reproduction. Folate deficiency can result in a type of anaemia called ‘megaloblastic anaemia’ which is a blood disorder characterised by the presence of enlarged immature and dysfunctional red blood cells (megablasts).
How much folate is recommended?
It is recommended that New Zealand adults consume around 400 micrograms (µg) of folate each day. Daily folate requirements increase substantially for pregnant and breastfeeding women and therefore they are recommended to consume around 600 and 500 µg of folate each day, respectively. For more information, see Supplement (tablet) to take when pregnant or breastfeeding.
Why do we need folic acid?
Studies from the 1980s and 1990s showed that folic acid can help ensure healthy development of babies in early pregnancy. In 1999 Berry et al conclusively found that a daily dose of 400 µg of folic acid alone resulted in a reduction in neural tube defect risk (first occurrence) similar to that reported in earlier studies, when taken at least one month before conception and for 12 weeks after conceiving.
More information can be found about this research in the publication Improving Folate Intake in New Zealand: Policy Implications [in the Ministry's Library Catalogue].
What is a neural tube defect (NTD)?
Neural tube defects (NTDs) are a major group of birth defects where the brain, spinal cord, or the covering of these organs has not developed properly. Spina bifida and anencephaly are the most common types of NTDs.
Spina bifida, is the most common NTD. It results from the failure of the spine to close properly during the first month of pregnancy. Children with spina bifida can have varying degrees of paralysis of their lower limbs – some children can be confined to a wheelchair whereas others have almost no symptoms at all. The condition can also cause bowel and bladder problems.
Babies born with anencephaly have underdeveloped brains and incomplete skulls. Most infants born with anencephaly do not survive more than a few hours after birth.
How common are neural tube defects in New Zealand?
In 2003 NTD rates were the highest in early pregnancy terminations (5.7 cases per 10,000 total births), followed by live births (3.4 per 10,000) and fetal deaths (2.1 per 10,000).
What is the current policy on folic acid supplementation for reducing NTDs?
New Zealand's current policy for folic acid supplementation is as follows:
- Women at low risk of a NTD affected pregnancy who plan to become pregnant, are recommended to take a 800 µg of folic acid daily for at least four weeks prior to conception and for 12 weeks after conceiving to reduce the risk of NTDs. More information can be found in the the Health Education resource Folic Acid and Iodine.
- Women who are themselves affected with a NTD, or who have had a child with a NTD, or a close family member who has had a NTD, or whose partner is affected or had a family history of NTD, are recommended to take a higher dose of 5000 µg (5 mg) of folic acid daily with subsequent pregnancies for at least four weeks prior to conception and for 12 weeks after conceiving to reduce the risk of NTDs.
- A daily folic acid tablet of 5 mg is also recommended for women who are on insulin treatment for diabetes for at least four weeks prior to conception and for 12 weeks after conception to reduce the risk of NTDs.
- A daily folic acid tablet of 5 mg is also recommended for women who are taking medications known to affect folate metabolism such as anti-convulsants, infertility treatment, vitamin A analogues used to treat acne and some anti-tumor agents; for example, carbemazepine, clomiphene, valproate, retinoids and etretinate. This tablet should be taken for at least four weeks prior to conception and for 12 weeks after conception to reduce the risk of NTDs
All recommendations have evolved in a food environment where voluntary addition of folic acid addition to certain foods has been permitted since 1996. Currently some cereals and cereal products, bread, and fruit juice have folic acid voluntarily added to them by food manufactures.
Currently a subsidised 800 µg and 5mg folic acid tablet are the only subsidised registered medicines available over the counter from pharmacies in New Zealand. These folic acid only tablets are what the Ministry of Health recommends for women for at least four weeks prior to conception and for 12 weeks after conception to reduce the risk of NTDs.
More background can be found about these recommendations in the publication Food and Nutrition Guidelines for Healthy Pregnant and Breastfeeding Women.
Can we increase folate intake?
Folate is found naturally in green leafy vegetables (such as spinach and broccoli), citrus fruits and juices, wholemeal bread and legumes. Animal liver is also a rich source of folate. However, it is difficult to get enough folate from natural sources to reduce the risk of a NTD affected pregnancy as natural folate is not so easily absorbed as a folic acid supplement.
For example, if women relied on green leafy vegetables and fruit to increase their folate intake, they would have to eat the equivalent of 500g of raw spinach or 900g of boiled spinach or raw broccoli daily to get the amount needed to reduce the risk of having a baby with a neural tube defect.
Further information on eating well for pregnancy can be found the Health Education resource Eating For Healthy Pregnant Women or your local public health unit.
Why do women planning a pregnancy need to take a folic acid supplement?
Women planning a pregnancy need to take a daily dose of folic acid. This dose will either be a low dose of 800 µg day, or a high dose of 5 mg day of folic acid, depending on the perceived risk of having a NTD affected pregnancy, for at least four weeks before conception and 12 weeks after conception. For more information, see Supplement (tablet) to take when pregnant or breastfeeding.
Are there any adverse effects to taking the recommended folic acid tablet?
None are known at current recommended levels of intake.
High doses of folic acid are not known to have any adverse effects on healthy individuals at current recommended levels of intake. Research in this field continues with some negative health consequences suggested. For example, high levels of folic acid may mask vitamin B12 deficiency in certain groups such as the elderly and the young, thus delaying diagnosis. Food Standards Australia New Zealand notes that masking of vitamin B12 deficiency is unlikely to occur if intakes of folic acid are less than 1 mg a day.
What do other countries do?
Mandatory fortification with folic acid:
- USA – has had mandatory fortification of all cereal/grain flours with folic acid since 1998.
- Canada – white flour and pasta has been mandatorily fortified since 1998.
- Chile – introduced mandatory fortification of flour in 2000.
- Australia – introduced mandatory fortification of bread-making flour in late 2009.
Food Standards Australia New Zealand (FSANZ) develops food standards for both New Zealand and Australia, and have responsibility for implementing mandatory fortification of bread-making flour with folic acid, industry compliance and monitoring the food supply in Australia. View their fact sheet: Mandatory folic acid fortification in Australia.
Voluntary fortification with folic acid:
- European countries – to date, none have introduced mandatory fortification with folic acid.
- UK and Ireland – continue to permit voluntary fortification of certain foods with folic acid.
- New Zealand – has deferred the mandatory fortification of bread with folic acid until May 2012.
The Ministry of Primary Industries has responsibility for folic acid voluntary fortification, including industry compliance and monitoring the food supply in New Zealand. View the list of fortified breads (PDF, 9 KB) on their FoodSmart website.
Recommendations for women planning a pregnancy:
USA, Canada, Australia, UK and Ireland recommend women planning a pregnancy take a folic acid tablet in the range of 400–500 µg for women at low risk of a NTD affected pregnancy.