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H E A LT H Folic acid and the prevention of NTDs Adequate levels of folic acid in the mother’s body at conception and in the early stages of pregnancy can prevent serious birth defects, such as spina bifida. But pregnancy can be a surprise. This makes getting the message to those most at risk a real challenge. The National Committee on Folic Acid Food Fortification was established in 2004. The Committee is looking at the issue of fortifying foods with folic acid in light of the relatively high levels of neural tube defects (NTDs) in Ireland of data on pregnancies that do not reach full term and the lack of a national congenital defects birth register in Ireland. NTDs are a group of birth defects that result in abnormalities in the Genetics. and evidence that folic acid consumption can reduce the incidence of these birth defects. The Committee report, published in 2006, highlighted that the incidence of NTDs in Ireland is higher than in the rest of Europe. In 2004, it was estimated that 1.5 in every 1000 babies are born with an NTD each year. The report also noted the central nervous system and spinal cord. These occur in the first few weeks of pregnancy. The most common NTD is spina bifida. The spinal defect can sometimes be repaired through surgery, but surgery is not always a solution. Most babies born with spina bifida will survive but will have moderate to severe handicap. More severe NTDs, Early pregnancy. actual incidence of NTDs may be under-estimated because of the absence such as anencephaly and iniencephaly, are fatal. AT A GLANCE NTDs. 258 consumer choice JULY 2008 HEALTH Folate and folic acid The B vitamin, folate, occurs naturally in foods. Good natural dietary sources of folate include: green vegetables, especially asparagus, broccoli, green beans, peas and spinach. Other good sources include: cauliflower, eggs, potatoes, oranges and orange juice. But as with many vitamins, folate is easily destroyed during cooking, food processing and even if fruit or vegetables are over-ripe or bruised. Folic acid, the synthetic form of folate, is most commonly used in vitamin supplements and fortified foods. See our tables for the folic acid content of a range of vitamin supplements and a variation within certain genes can also influence how well folate is used in the body. Down to the genes It has been found that a section of the Irish population have a genetic predisposition to metabolise folate differently. Research based in Ireland has identified variations in at least two genes that can increase the risk of having a baby with an NTD. This leaves some individuals with a greater risk due to their genetic makeup. Up to half of folate related NTDs are thought to be explained by one of these genes, known as MTHFR. A 2004 paper published in the British Medical Journal showed that the link between MTHFR genotype and NTD risk was greater than previously thought. This means that some women need more folic acid than others, not these birth defects. But this may prove to be another challenge. Useful contacts Food Safety Who needs folic acid? Authority of Ireland It has been found that there is a high level of public awareness of the importance of taking folic acid during pregnancy. The advice is that folic acid supplements at a level of 400µg should be taken prior to conception and for the first twelve weeks Abbey Court of pregnancy. However, being aware of this fact does not always mean it is acted upon. Also, the time when folic acid is taken is crucial to prevent NTDs. When pregnancies are planned and folic acid is taken, this most often starts when the pregnancy is confirmed. This is too late as the neural tube is completely developed between 21 and 28 days after conception. Research from the UK published in Public Health Nutrition found that a large proportion of women reported www.fsai.ie Lower Abbey Street Dublin 1 Advice 1890 336 677 tel (01) 817 1300 fax (01) 817 1301 email [email protected] The Irish Association for Spina Bifida and Hydrocephalus National Resource Centre Old Nangor Road Clondalkin Dublin 22 1890 20 22 60 tel (01) 457 2329 fax (01) 457 2328 “When only a specific group of the population has higher folic acid needs, we must ask whether mandatory fortification of bread is the right approach.” www.iasbah.ie Irish Nutrition and Dietetic Association Ashgrove House Kill Avenue Dun Laoghaire Co. Dublin email [email protected] www.indi.ie selection of fortified foods. You may also see a blue symbol on some foods stating ‘with extra folic acid’ or ‘contains just because natural dietary sources of folate may be less effectively absorbed than synthetic folic acid, but because of folic acid’. This symbol has been devised by the Food Safety Authority of Ireland (FSAI, see Useful contacts) to indicate that food has been fortified. Research has shown that folic acid is better absorbed by the body than natural folate. This can also be referred to as ‘bioavailability’. Foods that have natural folate can contain inhibitors that block the absorption of the vitamin. Folic acid, the synthetic form of folate, is not easily destroyed or this genetic predisposition. For most adults, the Recommended Daily Allowance (RDA) of folate is 200 micrograms (µg) per day. However, for women of childbearing age, an intake of 400µg of folic acid per day is recommended to protect their pregnancy against the development of NTDs. However, the Irish Association for Spina Bifida and Hydrocephalus (see Useful contacts) recommends that women with a higher risk of having a affected by inhibitors. This means the body can then make better use of the vitamin in the synthetic form. However, natural food sources of folate still make a vital contribution to our daily intake. Research published last year in the American Journal of Clinical Nutrition found that the baby with an NTD need to take as much as 4000µg per day, ten times the recommended amount for women of childbearing age. Family history of the presence of NTDs is one sign of those who are at risk. For women in the higher risk category, eating foods naturally high in bioavailability of the natural folates can be as high as 80% of that of folic acid. Foods naturally high in folate are also good sources of other valuable vitamins and fibre. Besides folate bioavailability, folate or food fortified with folic acid will not provide the required amount of folate to protect against having a baby with an NTD. Those in the high risk category should be identified and targeted to help reduce the incidence of taking folic acid during pregnancy. However, more significantly, most did not take it in early pregnancy when it is most needed to protect against NTDs. It was also found that those from lower socio-economic groups were much less likely to take folic acid when it is most critical. Younger women were less likely to take folic acid at all. This evidence is also reflected in Ireland’s population. Research carried out in Ireland from 2001-3 found that folic acid is often not taken before conception. It was also found that younger, poorer and less educated women were the least likely to take folic acid. Useful websites European Food Information Council www.eufic.org Folic acid, today and everyday www.folicacid.ie Catch 22? Planning for the unplanned The Committee report highlights that about half of all pregnancies in Ireland are unplanned. There is an inherent contradiction here that makes it more difficult to address the need for women to take folic acid before they conceive. Folic acid is needed at adequate levels in the early stages of pregnancy to help prevent NTDs. But if women are not planning on having a baby, with the HEALTH JULY 2008 consumer choice Report by Aisling Murtagh cc 259 FOLIC ACID CONTENT Folic acid per dose (µg) Supplement B VITAMINS Berocca Plus effervescent 366 Solgar B complex ‘50’ tablets 400 Sona B complex tablets 400 Quest Multi B complex 400 Viridian B complex High Five capsules 200 FOLIC ACID SUPPLEMENTS general pressures and worries of life, it is unlikely they will prioritise one issue and one nutrient. Women who are not planning pregnancy are more likely to use contraception, such as the pill. Would adding folic acid to the contraceptive pill go some short way to lessening the risk? Such a move may be controversial in itself. Or is there another solution? Clonfolic folic acid tablets 400 Sona folic acid tablets 400 Food fortification Viridian folic acid capsules 400 The issues are clear, but the solutions are not. However, in 2006 the National Committee on Folic Acid Food Fortification recommended that most white, brown and wholemeal bread on sale in Ireland should be fortified with 120µg of folic acid per 100g. The aim is to increase folic acid intake in all women of IRON SUPPLEMENTS Sona iron complete liquid 100 Vitabiotics Feroglobin capsules 500 MULTIVITAMINS Centrum Complete tablets 200 Seven Seas Multibionta tablets 200 Solgar VM-75 tablets 400 Sona Multiplus capsules 400 Quest Super Once a Day tablets 200 Sona Calcium Complete tablets 200 Vitabiotics Skin, Hair and Nails capsules 500 childbearing age. It was also recommended that monitoring is an essential part of a fortification programme, to ensure it is effective and safe. Mandatory folic acid fortification of foods has already been introduced in other countries, such as the US, Canada, Chile, Brazil, Indonesia and Israel. In the case of the US, it has been documented that this has led to Alpro light unsweetened soya milk 85 per 250ml a decline in the incidence of NTDs. Research from 2002 found that the increase in folic acid in the Avonmore Supermilk 70 per 100ml Brennans sliced white bread 19 per slice Dairygold light 100 per 10g serving Flora vegetable spread 100 per 10g serving Kelloggs breakfast cereals1 58 per 30g serving Kelloggs Nutrigrain bar 50 per bar SUPPLEMENTS FOR PREGNANCY Vitabiotics Pregnacare tablets 400 Viridian Pregnancy Complex capsules 400 SUPPLEMENTS FOR WOMEN Solgar Female Multiple tablets 800 Vitabiotics Wellwoman capsules 400 OTHER SUPPLEMENTS Pharmaton capsules 100 FORTIFIED FOODS: FOLIC ACID CONTENT Kelloggs Special K cereal bar2 34 per bar Nestle breakfast cereals1 51 per 30g serving 1 Folic acid content may vary slightly depending on cereal and serving size. 2 Kelloggs cereal bars in general are fortified, folic acid content may vary depending on size of bar. population was double than expected. However, all flour in the US is fortified with folic acid at the level of 140µg per 100g of grain. But regardless, this creates another question that needs addressing: what are the implications of fortifying bread with folic acid for those outside of the target category? There are reported risks and benefits beyond NTD prevention. choice comment Mandatory folic acid fortification of foods has great potential benefit. However, the time and circumstance in life when we consume more or less folic acid has an impact on whether it is beneficial. A high intake is not best for the elderly and those with polyps in the bowel, which are more common in the over 50s. On the other hand, it is essential to ensure women of childbearing age get enough folic acid to prevent NTDs. The key point seems that most women know they should take folic acid, but also need to become aware of when it is most important. It is vital to have enough folic acid in the body pre-conception and in the early stages of pregnancy. When only a specific group of the population has higher folic acid needs, we must ask whether mandatory fortification of bread is the right approach. This could also increase the folic acid intake of those who don’t need it. To retain consumer choice, it is proposed that only some breads will be fortified. Is this enough to allow consumers to make informed choices? Consumers must be made aware of which foods contain added folic acid, especially since extra folic acid is not good for some consumers and they may not be aware of this. This issue goes beyond mandatory fortification. Many foods and food supplements already contain folic acid at varying levels. It also raises another issue - the need for greater regulation of voluntary fortification of foods with all nutrients - not just folic acid. 260 consumer choice JULY 2008 HEALTH Benefits There are general nutritional benefits from having an adequate intake of folic acid. It supports the nervous system and general cell function. The genetic predisposition discussed earlier does not just relate to NTDs, but has also been found to contribute to a greater risk of developing other diseases, such as cancer, heart and Alzheimer’s disease, because of the inadequate use of folate in the body. Risks Increased intake of folic acid in the elderly has been found to mask vitamin B12 deficiency. This can then enhance the deterioration of nervous system functioning that result from B12 deficiency, if undiagnosed. Questions have also been raised regarding the potential effects of stores of unused folic acid in the liver. Research has also suggested that taking folic acid supplements can increase the risk of bowel cancer in at risk populations, such as those who have polyps in the colon. These are more common in the over 50s. While most polyps will not develop into cancer, high levels of folic acid can accelerate the process where cells may become cancerous. This is worrying when we look at the fact that bowel cancer is the second most common cancer in Ireland (skin cancer being the most common). Mandatory fortification of folic acid has also been proposed in the UK. The issue is currently on hold pending an expert review of evidence relating to bowel cancer risk and folic acid. This review is not expected to be concluded until mid-2009. It is important to highlight that when the link between bowel cancer risk and folic acid has been made, high levels of folic acid were consumed, well above the RDA. In Ireland, recommendations from the mandatory fortification programme have set an upper limit on the amount of folic acid to be added to bread (120µg per 100g). This aims to provide protection against a high intake occurring in the general population. Folic acid is a vitamin we all need. We must keep in mind that there is a distinction between the benefits of folic acid at recommended levels, and the potential risks of a high intake.