1. ¹Institute of Food Research, Norwich Research Park, Colney, Norwich, UK
2. ²Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands
3. ³Department of Biochemistry, Trinity College Dublin, Dublin, Ireland
4. ⁴Wageningen Centre for Food Sciences & Division of Human Nutrition, Wageningen University, Wageningen, The Netherlands
5. ⁵Institute of Nutritional Sciences, University of Bonn, Bonn, Germany
6. ⁶Division of Clinical Sciences, Centre for Human Nutrition, University of Sheffield, Sheffield, UK
7. ⁷Department of Molecular Genetics, Ghent University, Gent, Belgium
8. ⁸Department of Food Science, Swedish University of Agricultural Sciences, Uppsala, Sweden
9. ⁹Departamento de Nutrición y Bromatología, Universidad San Pablo-CEU, Madrid, Spain
10. ¹⁰TNO Nutrition and Food Research, Zeist, The Netherlands
11. ¹¹British Nutrition Foundation, London, UK

Correspondence: Dr PM Finglas, Institute of Food Research, Norwich Research Park, Colney, Norwich, NR4 7UA Norfolk, UK.
E-mail: paul.finglas@bbsrc.ac.uk

Received 3 February 2005; Revised 18 August 2005; Accepted 7 September 2005; Published online 26 October 2005.

Abstract

In the past decade, the understanding of folate bioavailability, metabolism and related health issues has increased, but several problems remain, including the difficulty of delivering the available knowledge to the populations at risk. Owing to the low compliance of taking folic acid supplements, for example, among women of child-bearing age who could lower the risk of having a baby with a neural tube defect, food-based strategies aimed at increasing the intake of folate and other B-group vitamins should be a priority for future research. These should include the development of a combined strategy of supplemental folate (possibly with vitamin B₁₂), biofortification using engineered plant-derived foods and micro-organisms and food fortification for increasing folate intakes in the general population. Currently, the most effective population-based strategy to reduce NTDs remains folic acid fortification. However, the possible adverse effect of high intakes of folic acid on neurologic functioning among elderly persons with vitamin B₁₂ deficiency needs urgent investigation. The results of ongoing randomized controlled studies aimed at reducing the prevalence of hyperhomocysteinemia and related morbidity must be available before food-based total population approaches for treatment of hyperhomocysteinemia can be recommended. Further research is required on quantitative assessment of folate intake and bioavailability, along with a more thorough understanding of physiological, biochemical and genetic processes involved in folate absorption and metabolism.