Folic acid fortification and public health: Report on threshold doses above which unmetabolised folic acid appear in serum

详细信息    查看全文

• 作者：Mary Rose Sweeney (1) (3)
  Joseph McPartlin (1)
  John Scott (2)
  
• 刊名：BMC Public Health
• 出版年：2007
• 出版时间：December 2007
• 年：2007
• 卷：7
• 期：1
• 全文大小：576KB
• 参考文献：1. Quinlivan EP, Gregory JF: Effect of food fortification on folic acid intake in the United States. / Am J Clin Nutr 2003, 77: 221-.
  2. Oakley GP, Myron JR, Adams J, Dickinson CM: More folic acid for everyone, Now. American Institute of Nutrition 1996, 751S-755S.
  3. Sweeney MR, McPartlin J, Weir DG, Scott JM: Measurements of subnanamolar concentrations of unmetabolised folic acid in serum. / Journal of Chromotography B 2003, 788: 187-91. CrossRef
  4. Kelly P, Mc Partlin J, Scott JM: A combined High-Performance liquid chromatographic microbiological assay for serum unmetabolised folic acid. / Analytical Biochemistry 1996, 238: 179-83. CrossRef
  5. Sweeney MR, McPartlin J, Weir DJ, Daly L, Scott JM: Post-prandial serum folic acid response to multiple doses of folic acid in fortified bread. / Br J Nutr 2006, 94: 1-.
  6. Sweeney MR, McPartlin J, Weir DJ, Daly S, Pentieva K, Daly L, Scott JM: Evidence of unmetabolised folic acid in cord-blood of new-born and serum of four-day old infants. / BJN 2005, 94: 727-30. CrossRef
  7. Tisman G, Herbert V: B-12 dependence of cell uptake of serum folate: explanation for high serum folate and cell folate depletion in B-12 deficiency. / Blood 1973, 41: 465-.
  8. Metz J, Kelly A, Swett VC, Waxman S, Herbert V: Deranged DNA synthesis by bone marrow from vitamins B-12 deficient humans. / British Journal of Haematology 1968, 14: 572-2. CrossRef
  9. Zittoun J, Marquet J, Zittoun R: Effect of folate and cobalamin compounds on the deoxyuridine supression test in vitamin B-12 and folate deficiency. / Blood 1978, 51: 119-8.
  10. Ganeshaguru K, Hoffbrand AV: The effect of deoxyuridine, vitamin B -12, folate and alcohol on the uptake of thymidine and on the deoxynucleoside triphosphate concentrations in normal and megaloblastic cells. / British Journal of Haematology 1978, 40: 29-1. CrossRef
  11. Heinle RM, Welch AD: Folic acid in pernicious anaemia. Failure to prevent neurologic relapse. / JAMA 1974, 133: 739-41.
  12. Bethal FH, Stergis CC: The relation of therapy in pernicious anaemia to changes in the nervous system. Early and late results in a series of cases observed for periods of not less than ten years, and early results of treatment with folic acid. / Blood 1948, 3: 57-7.
  13. Ross JF, Belding H, Paegal BL: The development and progression of subacute combined degeneration of the spinal cord in patients with pernicious anaemia treated with synthetic pteroylglutamic (folic) acid. / Blood 1948, 3: 68-0.
  14. Vilter RW, Horrigan D, Mueller JF, Jarrold T, Vilter CF, Hawkins V, Seaman A: Studies on the relationships of vitamin B12, folic acid, thymine, uracil, and methyl group donors in persons with pernicious anaemia and related megaloblastic anaemias. / Blood 1950, 5: 695-17.
  15. Israels MCG, Wilkinson JF: Risk of neurological complications in pernicious anaemia treated with folic acid. / British Medical Journal 1949, (ii) : 1072-075.
  16. Food and Drug Administration: Food labelling: health claims and food label statements; folate and neural tube defects. / Federal Register 1996, 61 (44) : 8752-07.
  17. Troen AM, / et al.: Unmetabolised folic acid in plasma is associated with reduced natural killer cell cytotoxicity among post-menapausal women. / J Nutr 2006, 136: 189-94.
  18. Stolzenberg-Solomon RZ, Chang SC, Leitzmann MF, Johnson KA, Johnson C, Buys SS, Hoover RN, Ziegler RG: Folate intake, alcohol use and postmenopausal breast cancer risk in the prostate, lung, colorectal, and ovarian cancer screening trial. / Am J Clin Nutr 2006, 83: 895-04.
  19. Kim Young-In: Will mandatory folic acid fortification prevent or promote cancer. / American Journal of Clinical Nutrition 2004, 80 (5) : 1123-128.
  20. Charles D, Ness AR, Campbell D, Smith GD, Hall MH: Taking folate in pregnancy and risk of maternal cancer. / British Medical Journal 2004, 329: 1375-376. CrossRef
  21. Lucock M, Yates Z: Folic acid -vitamin and panacea or genetic time bomb? / Nat Rev Genet 2005, 6: 235-40. CrossRef
  22. Sweeney MR: Folic Acid Fortification of Flour: Determination of the level that gives rise to unmetabolised folic acid in serum. / Ph D thesis Trinity College, Republic of Ireland 2000.
  23. Ward M, McNulty H, McPartlin J, Strain JJ, Weir DG, Scott JM: Plasma homocysteine, a risk factor for cardiovascular disease, is lowered by physiological doses of folic acid. / Quarterly Journal of Medicine 1997, 90: 519-24.
  24. Molloy A, Scott JM: Microbiological assay for serum, plasma and red cell folate using cryopreserved microtitre plate method. / Methods in Enzymology 1997, 281: 43-3. CrossRef
  25. Department of Health: Folic acid and the prevention of Neural Tube Defects. / Report from an Expert Advisory Group London: Department of Health 1992.
  26. The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-2458/7/41/prepub
  
• 作者单位：Mary Rose Sweeney (1) (3)
  Joseph McPartlin (1)
  John Scott (2)
  
  1. From the Department of Clinical Medicine, Trinity College, Dublin, Ireland
  3. UCD School of Public Health Population Science, University College Dublin, Dublin, Ireland
  2. Department of Biochemistry, Trinity College, Dublin, Ireland
  
• ISSN：1471-2458

文摘

Background All flour in the USA is fortified with folic acid at a level of 140 μg/100 g which is estimated to supply an extra 100 μg daily to the average diet. Some researchers have advocated that this be increased to double and even four times this amount. Based on previous research these higher levels are likely to lead to the appearance of unmetabolised vitamin in the circulation, which may have safety implications for sub-groups of the population. The UK and the Republic of Ireland will likely introduce mandatory fortification also in the next year or so. The aim of this study was to capture the short-term effect of folic acid fortification on unmetabolised folic acid in serum after chronic consumption of folic acid. Methods After pre-saturation with 400 μg folic acid supplements daily for 14-weeks, healthy folate replete adults (n = 20) consumed folic acid fortified bread, at three different levels (400 μg, 200 μg, 100 μg) over a period of one week each. The dose was administered in two-equal sized slices consumed at 09.00 hrs and 13.00 hrs. Serum samples for total folate and folic acid were collected at baseline, after 14-weeks of supplementation, and pre and post (at 1, 2, 3 and 4 hours) each dose tested. Results Unmetabolised folic acid was detected after the 14-week supplementation period. Folic acid was not detected in either the 200 μg or 100 μg (current US regime) doses tested but was present at the highest level (400 μg) tested. Conclusion Our findings suggest that persons exposed to the current US fortification programme supplying an average of 100 μg per day or less are unlikely to have unmetabolised folic acid in serum. It also seems that daily consumption of the higher level of 200 μg or less is unlikely to be problematic. Increasing the level however to 400 μg on the other hand is likely to lead to unmetabolised folic acid appearance.