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| Food composition tables are central to the development of many public health policies but they have been a particularly important tool in the ongoing discussions about the possible benefits versus risks of folic acid fortification in Europe.
It is now well recognised that taking folic acid supplements before pregnancy and in the first 12 weeks can reduce the risk of neural tube defects such as spina bifida and anencepthaly, in the developing fetus and may be associated with other health benefits in relation to cancer and cardiovascular disease (Williamson 2006; SACN 2005). | |  | |
| Approximately 4,500 pregnancies every year in Europe result in a livebirth, stillbirth or termination of pregnancy of a baby/fetus affected by an neural tube defect. A trial by the Medical Research Council in 1991 suggested that up to 70% of these might be prevented by consumption of folic acid (MRC Vitamin Study Research Group, 1991). This has led governments around the world to recommend supplementation for women of childbearing age, particularly those considering pregnancy, along with advice to consume foods providing folate (e.g. green leafy vegetables, citrus fruit, legumes) and folic acid (e.g. fortified cereals, bread, yeast extract). | |
| Whilst there have been several government campaigns to increase awareness of the importance of this message, the majority of women in Europe are not taking folic acid supplements at the correct time (EUROCAT 2005). Many pregnancies are still unplanned resulting in a large proportion of women delaying folic acid supplement use until too late (Buttriss 2004). The situation regarding low uptake of supplementation advice is reflected in the lack of a significant decline in the prevalence of neural tube defects across Europe in recent years. National surveys, such as the National Diet and Nutrition Survey in the UK, have also suggested that many people, particularly young women and the elderly, may have poor dietary intakes of this vitamin (Henderson et al. 2003). Folic acid fortification of a staple food (e.g. flour) has been advocated as the most effective way to reach all women in the very early stages of pregnancy, when a large proportion will be unaware that they are.This work was completed on behalf of the EuroFIR Consortium (FOOD-CT-2005-513944) and funded under the EU 6th Framework Food Quality and Safety Programme pregnant. It is also the preferred method to include women who are unlikely to receive or respond to health promotion messages. | |
| Where are we with folic acid fortification in Europe? | |
| Mandatory fortification of a staple food (usually flour) with folic acid has been seriously considered in a number of European countries including Denmark, Germany, Ireland, Norway, Poland, Switzerland, and the UK but none have yet introduced it. The lack of any action is primarily because of concerns that raised intakes may mask vitamin B12 deficiency anaemia in the elderly population. However, the pros and cons of fortification continue to be debated in several European countries. | |
| For example, in the UK, the Scientific Advisory Committee on Nutrition recently reviewed the evidence regarding the health benefits of dietary folate and recommended mandatory addition of the vitamin to four (SACN 2005). However, the UK’s Food Standards Agency has stated that it requires more time to make a full assessment of the implications of studies raising folate intake over 1 mg per day and to allow further analysis of national nutrition survey data to inform any fortification strategy. | |
| Ireland’s National Committee on Folic Acid Fortification has also recently recommended that most white, brown and wholemeal breads sold in the country be fortified with 120 micrograms of folic acid per 100g of bread (Food Safety Authority of Ireland & Department of Health and Children 2006). Ireland has one of the highestrates of neural tube defects in Europe with approximately 1-1.5 per 1,000 births nationally, equating to between 49 and 93 babies, affected each year. Although supplements containing 400 micrograms per day are promoted, the committee only recommended 120 micrograms to allow a good safety margin for those who consume large amounts of bread. Excluding some minor bread products and retail flour from the requirements has also been suggested to improve consumer choice so that those wishing to avoid fortified products are able to do so. | |
| The reluctance to proceed to mandatory food fortification with folic acid in Europe has been fuelled primarily by concern regarding the potential risk of masking the symptoms of pernicious anaemia caused by vitamin B12 deficiency. If undiagnosed, there is potential for irreversible neurological damage in those at high risk of this This work was completed on behalf of the EuroFIR Consortium (FOOD-CT-2005-513944) and funded under the EU 6th Framework Food Quality and Safety Programme deficiency, namely the elderly. Fortifying flour with vitamin B12 along with folic acid does not seem to be a feasible option as the high dose of B12 required to improve status among elderly people could put others in the population at risk of excess intakes. Any action on fortification with folic acid would, however, need to consider the adequacy of arrangements to routinely detect B12 deficiency. There have been some reports of possible increases in twinning associated with periconceptional folic acid but this association is thought by many researchers to be due to the confounding effect of folic acid supplementation being much more common among women using assisted reproductive technology and the fact that use of this technology may be significantly under-reported (Berry et al. 2005). There is concern, however, about the possibility that high intakes of folic acid may enhance the development of undiagnosed pre-malignant and malignant lesions. | |
| Using food composition tables to assess risk | |
| In order to assess the risks and benefits of fortification, food composition data together with dietary intake information has been used to model likely folic acid intakes in different groups. This has informed discussions regarding the specific level for fortification that might improve folate status to reduce risk of neural tube defects without risking excessive intakes. National dietary data has also been used to identify those subgroups that may be at risk of B12 deficiency. | |
| Lessons from other countries | |
| In recent years the US, Canada, Chile and the Czech Republic have all introduced mandatory fortification of flour with folic acid to ensure that all pregnant women are receiving adequate amounts of the nutrient. Despite the fact that the amount of folic acid added into the food supply does not provide enough to fully protect unborn children, recent reports from Canada and the USA indicate fortification of cereal grains has been very effective, with reduction in neural tube defects of between 27% and 50% (SACN 2005). Rates of cardiovascular disease also appears to have fallen. Unfortunately, there are as yet no data from these countries on population trends in the incidence of B12 deficiency or any related neurological damage that can help to clarify the risks involved. | |
| The issue of whether or not to implement mandatory fortification of food with folic acid continues to be debated in Europe. It is likely that only a fortification policy will result in large-scale prevention of neural tube defects but fears about possible side effects, particularly amongst the elderly, must be alleviated to stimulate actionthroughout the EU. | |
| This work was completed on behalf of the EuroFIR Consortium (FOOD-CT-2005-513944) and funded under the EU 6th Framework Food Quality and Safety Programme | |
| Berry RJ, Kihlberg R, Devine O. Impact of misclassification of in vitro fertilisation in studies of folic acid and twinning: modelling using population based Swedish vitalrecords. British Medical Journal 330: 815. | |
| Buttriss JL (2004) Strategies to increase folate/folic acid intake in women: an overview. Nutrition Bulletin 29: 234-44. | |
| EUROCAT Folic Acid Working Group (2005) European Surveillance of Congenital anomalies. Prevention of Neural Tube Defects by Periconceptional Folic Acid Supplementation in Europe. Available at:http://www.eurocat.ulster.ac.uk/pdf/NTD%20Part%20I%20December%202005.pdf | |
| Henderson Gregorz J, Irving K et al. (2003) The National Diet and Nutrition Survy: Adults Aged 19-64 years, Volume 3: vitamin and mineral intake and urinary analytes. HMSO: London. | |
| MRC Vitamin Study Research Group (1991) Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. Lancet 338: 131-7. | |
| Williamson C (2006) Nutrition in Pregnancy. Nutrition Bulletin 31: 29-60. | |
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