Health Professionals:

Research on Folic Acid

Aisen P, Schneider L, Sano M, et al. High-dose B vitamin supplementation and cognitive decline in Alzheimer disease: A randomized controlled trial. JAMA. 2008;300(15):1774-1783.

Al-Delaimy WK, Rexrode KM, Hu FB, et al. Folate intake and risk of stroke among women. Stroke. 2004;35(6):1259-1263.

Almeida O, McCaul K, Hankey G, Norman P, Jamrozik K, Flicker L. Homocysteine and depression in later life. Arch Gen Psychiatry. 2008;65(11):1286-1294.

Almeida OP, Ford AH, Flicker L. Systematic review and meta-analysis of randomized placebo-controlled trials of folate and vitamin B12 for depression. Int Psychogeriatr. 2015;27(5):727-737.

Anderson JL, Jensen KR, Carlquist JF, Bair TL, Horne BD, Muhlestein JB. Effect of folic acid fortification of food on homocysteine-related mortality. Am J Med. 2004;116(3):158-164.

Badovinac RL, Werler MM, Williams PL, Kelsey KT, Hayes C. Folic acid-containing supplement consumption during pregnancy and risk for oral clefts: a meta-analysis. Birth Defects Res A Clin Mol Teratol. 2007;79:8-15.

Bailey LB, Stover PJ, McNulty H, et al. Biomarkers of nutrition for development-folate review. J Nutr. 2015;145(7):1636S-1680S.

Balogun OO, da Silva Lopes K, Ota E, et al. Vitamin supplementation for preventing miscarriage. Cochrane Database Syst Rev. 2016;(5):CD004073. doi: 10.1002/14651858.CD004073.pub4.

Bedson E, Bell D, Carr D, et al. Folate augmentation of treatment--evaluation for depression (FolATED): randomised trial and economic evaluation. Health Technol Assess. 2014;18(48):vii-viii, 1-159.

Berger SH, Pittman DL, Wyatt MD. Uracil in DNA: consequences for carcinogenesis and chemotherapy. Biochem Pharmacol. 2008;76(6):697-706.

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 vital records. BMJ. 2005;330(7495):815.

Berry RJ, Li Z, Erickson JD, et al. Prevention of neural-tube defects with folic acid in China. China-U.S. Collaborative Project for Neural Tube Defect Prevention. N Engl J Med. 1999;341(20):1485-1490.

Beydoun M, Shroff M, Beydoun H, Zonderman A. Serum folate, vitamin B-12, and homocysteine and their association with depressive symptoms among U.S. adults. Psychosom Med. 2010;72(9):862-873.

Bjelland I, Tell GS, Vollset SE, Refsum H, Ueland PM. Folate, vitamin B12, homocysteine, and the MTHFR 677C->T polymorphism in anxiety and depression: the Hordaland Homocysteine Study. Arch Gen Psychiatry. 2003;60(6):618-626.

Blount BC, Mack MM, Wehr CM, et al. Folate deficiency causes uracil misincorporation into human DNA and chromosome breakage: implications for cancer and neuronal damage. Proc Natl Acad Sci U S A. 1997;94(7):3290-3295.

Botto LD, Mulinare J, Erickson JD. Occurrence of congenital heart defects in relation to maternal multivitamin use. Am J Epidemiol. 2000;151(9):878-884.

Bower C, Miller M, Payne J, Serna P. Folate intake and the primary prevention of non-neural birth defects. Aust N Z J Public Health. 2006;30:258-261.

Bower C, Stanley FJ. Dietary folate as a risk factor for neural-tube defects: evidence from a case-control study in Western Australia. Med J Aust. 1989;150(11):613-619.

Bozzano L, Reynolds K, Holder K, He J. Effect of Folic Acid Supplementation on Risk of Cardiovascular Diseases: A meta-analysis of randomized controlled trials. JAMA. 2006;296:2720-2726.

Bukowski R, Malone FD, Porter FT, et al. Preconceptional folate supplementation and the risk of spontaneous preterm birth: A cohort study. PLoS Med. 2009; 6(5):e1000061.

Butterworth CE Jr, Hatch KD, Macaluso M, et al. Folate deficiency and cervical dysplasia. JAMA. 1992;267(4):528-533.

Castillo-Lancellotti C, Tur JA, Uauy R. Impact of folic acid fortification of flour on neural tube defects: a systematic review. Public Health Nutr. 2013;16(5):901-911.

Centers for Disease Control and Prevention. Folate status in women of childbearing age--United States, 1999. MMWR Morb Mortal Wkly Rep. 2000;49(42):962-965.

Chen P, Li C, Li X, Li J, Chu R, Wang H. Higher dietary folate intake reduces the breast cancer risk: a systematic review and meta-analysis. Br J Cancer. 2014;110(9):2327-2338.

Cho E, Hunter DJ, Spiegelman D, et al. Intakes of Vitamins A, C, and E and folate and multivitamins and lung cancer: a pooled analysis of 8 prospective studies. Int J Cancer. 2006;118:970-978.

Choumenkovitch SF, Jacques PF, Nadeau MR, Wilson PW, Rosenberg IH, Selhub J. Folic acid fortification increases red blood cell folate concentrations in the Framingham study. J Nutr. 2001;131(12):3277-3280.

Christen WG, Ajani UA, Glynn RJ, Hennekens CH. Blood levels of homocysteine and increased risks of cardiovascular disease: causal or casual? Arch Intern Med. 2000;160(4):422-434.

Chuang SC, Rota M, Gunter MJ, et al. Quantifying the dose-response relationship between circulating folate concentrations and colorectal cancer in cohort studies: a meta-analysis based on a flexible meta-regression model. Am J Epidemiol. 2013;178(7):1028-1037.

Clarke R, Halsey J, Lewington S, et al. Effects of lowering homocysteine levels with B vitamins on cardiovascular disease, cancer, and cause-specific mortality: Meta-analysis of 8 randomized trials involving 37485 individuals. Arch Intern Med. 2010;170(18):1622-1631.

Cole BF, Baron JA, Sandler RS, et al. Folic acid for the prevention of colorectal adenomas: a randomized clinical trial. JAMA. 2007;297(21):2351-2359.

Czeizel AE. Limb-reduction defects and folic acid supplementation. Lancet. 1995;345(8954):932.

Czeizel AE. Periconceptional folic acid containing multivitamin supplementation. Eur J Obstet Gynecol Reprod Biol. 1998;78(2):151-161.

Czeizel AE. Prevention of congenital abnormalities by periconceptional multivitamin supplementation. BMJ. 1993;306(6893):1645-1648.

Czeizel AE, Dudas I. Prevention of the first occurrence of neural-tube defects by periconceptional vitamin supplementation. N Engl J Med. 1992;327(26):1832-1835.

Czeizel AE. Reduction of urinary tract and cardiovascular defects by periconceptional multivitamin supplementation. Am J Med Genet. 1996;62(2):179-183.

Czeizel AE, Dobo M, Vargha P. Hungarian cohort-controlled trial of periconceptional multivitamin supplementation shows a reduction in certain congenital abnormalities. Birth Defects Res A Clin Mol Teratol. 2004;70(11):853-861.

Czeizel AE, Dudas I, Metneki J. Pregnancy outcomes in a randomised controlled trial of periconceptional multivitamin supplementation. Final report. Arch Gynecol Obstet. 1994;255(3):131-139.

Czeizel AE, Metneki J, Dudas I. Higher rate of multiple births after periconceptional vitamin supplementation. N Engl J Med. 1994;330(23):1687-1688.

Czeizel AE, Puho EH, Langmar Z, Acs N, Banhidy F. Possible association of folic acid supplementation during pregnancy with reduction of preterm birth: a population-based study. Eur J Obstet and Gynecol Reprod Biol. 2010;148:135-140.

Czeizel AE, Timar L, Sarkozi A. Dose-dependent effect of folic acid on the prevention of orofacial clefts. Pediatrics. 1999;104(6):e66.

Debreceni B, Debreceni L. The role of homocysteine-lowering B-vitamins in the primary prevention of cardiovascular disease. Cardiovasc Ther. 2014;32(3):130-138.

De-Regil LM, Peña-Rosas JP, Fernández-Gaxiola AC, Rayco-Solon P. Effects and safety of periconceptional oral folate supplementation for preventing birth defects. Cochrane Database Syst Rev. 2015;(12):CD007950.

Durga J, van Boxtel M, Schouten E, et al. Effect of 3-year folic acid supplementation on cognitive function in older adults in the FACIT trial: a randomized, double blind, controlled trial. Lancet. 2007;369:208-216.

Fife J, Raniga S, Hider PN, Frizelle FA. Folic acid supplementation and colorectal cancer risk: a meta-analysis. Colorectal Dis. 2011;13(2):132-137.

Flatley JE, McNeir K, Balasubramani L, et al. Folate status and aberrant DNA methylation are associated with HPV infection and cervical pathogenesis. Cancer Epidemiol Biomarkers Prev. 2009;18(10):2782-2789.

Fuchs CS, Willett WC, Colditz GA, et al. The influence of folate and multivitamin use on the familial risk of colon cancer in women. Cancer Epidemiol Biomarkers Prev. 2002;11(3):227-234.

George L, Mills JL, Johansson AL, et al. Plasma folate levels and risk of spontaneous abortion. JAMA. 2002;288(15):1867-1873.

Gibson,TM, Weinstein SJ, Pfeiffer RM, et al. Pre- and postfortification intake of folate and risk of colorectal cancer in a large prospective cohort study in the United States. Am J Clin Nutr. 2011;94(4):1053-62.

Gilbody S, Lightfoot T, Sheldon T. Is low folate a risk for depression? A meta-analysis and exploration of heterogeneity. J Epidemiol Community Health. 2007;61:631-637

Gindler J, Li Z, Berry RJ, et al. Folic acid supplements during pregnancy and risk of miscarriage. Lancet. 2001;358(9284):796-800.

Giovannucci E, Stampfer MJ, Colditz GA, et al. Folate, methionine, and alcohol intake and risk of colorectal adenoma. J Natl Cancer Inst. 1993;85(11):875-884.

Giovannucci E, Stampfer MJ, Colditz GA, et al. Multivitamin use, folate, and colon cancer in women in the Nurses' Health Study. Ann Intern Med. 1998;129(7):517-524.

Godwin KA, Sibbald B, Bedard T, Kuzeljevic B, Lowry RB, Arbour L. Changes in frequencies of select congenital anomalies since the onset of folic acid fortification in a Canadian birth defect registry. Can J Public Health. 2008;99(4):271-275.

Groen In 't Woud S, Renkema KY, Schreuder MF, et al. Maternal risk factors involved in specific congenital anomalies of the kidney and urinary tract: A case-control study. Birth Defects Res A Clin Mol Teratol. 2016;106(7):596-603.

Halsted CH, Villanueva JA, Devlin AM, Chandler CJ. Metabolic interactions of alcohol and folate. J Nutr. 2002;132(8 Suppl):2367S-2372S.

Hankey GJ, Ford AH, Yi Q, et al. Effect of B vitamins and lowering homocysteine on cognitive impairment in patients with previous stroke or transient ischemic attack: a prespecified secondary analysis of a randomized, placebo-controlled trial and meta-analysis. Stroke. 2013;44(8):2232-2239.

He K, Merchant A, Rimm EB, et al. Folate, vitamin B6, and B12 intakes in relation to risk of stroke among men. Stroke. 2004;35(1):169-174.

He Y, Pan A, Hu FB, Ma X. Folic acid supplementation, birth defects, and adverse pregnancy outcomes in Chinese women: a population-based mega-cohort study. Lancet. 2016;388 Suppl 1:S91. doi: 10.1016/S0140-6736(16)32018-9.

Hernandez-Diaz S, Werler MM, Walker AM, Mitchell AA. Folic acid antagonists during pregnancy and the risk of birth defects. N Engl J Med. 2000;343(22):1608-1614.

Ho RCM, Cheung MWL, Fu E, et al. Is high homocysteine level a risk factor for cognitive decline in elderly? A systematic review, meta-analysis and meta-regression. Am J Geriatr Psychiatry. 2011;19(7):607-617.

Homocysteine Lowering Trialists' Collaboration. Lowering blood homocysteine with folic acid based supplements: meta-analysis of randomised trials. BMJ. 1998;316(7135):894-898.

Hook EB, Czeizel AE. Can terathanasia explain the protective effect of folic-acid supplementation on birth defects? Lancet. 1997;350:513-515.

Ionescu-Ittu R, Marelli AJ, Mackie AS, Pilote L. Prevalence of severe congenital heart disease after folic acid fortification of grain products: time trend analysis in Quebec, Canada. BMJ. 2009; 338:b1673.

Itikala PR, Watkins ML, Mulinare J, Moore CA, Liu Y. Maternal multivitamin use and orofacial clefts in offspring. Teratology. 2001;63(2):79-86.

Jacob RA, Gretz DM, Taylor PC, et al. Moderate folate depletion increases plasma homocysteine and decreases lymphocyte DNA methylation in postmenopausal women. J Nutr. 1998;128(7):1204-1212.

Jacques PF, Selhub J, Bostom AG, Wilson PW, Rosenberg IH. The effect of folic acid fortification on plasma folate and total homocysteine concentrations. N Engl J Med. 1999;340(19):1449-1454.

Jaszewksi R, Misra S, Tobi M, et al. Folic acid supplementation inhibits recurrence of colorectal adenomas: A randomized chemoprevention trial. World J Gastroenterol. 2008;14(28)4492-4498.

Ji Y, Tan S, Xu Y, et al. Vitamin B supplementation, homocysteine levels, and the risk of cerebrovascular disease: a meta-analysis. Neurology. 2013;81(15):1298-1307.

Kallen B. Use of folic acid supplementation and risk for dizygotic twinning. Early Hum Dev. 2004;80(2):143-151.

Kennedy DA, Sterns SJ, Moretti M, et al. Folate intake and the risk of colorectal cancer: a systematic review and meta-analysis. Cancer Epidemiol. 2011;35(1):2-10.

Kim DH, Smith-Warner SA, Spiegelman D, et al. Pooled analyses of 13 prospective cohort studies on folate intake and colon cancer. Cancer Causes Control. 2010;21(11):1919-1930

Kim Y. Folic Acid Supplementation and Cancer Risk: Point. Cancer Epidemiol Biomarkers Prev 2008;17(9):2220-2225.

Kucik J, Correa A. Trends in twinning rates in metropolitan Atlanta before and after folic acid fortification. J Reprod Med. 2004;49(9):707-712.

Kwasniewska A, Tukendorf A, Semczuk M. Folate deficiency and cervical intraepithelial neoplasia. Eur J Gynaecol Oncol. 1997;18(6):526-530.

Larsson S, Giovannucci E, Wolk A. Folate and risk of breast cancer: a meta-analysis. J Natl Cancer Inst. 2007;99:64-76.

Larsson S, Giovannucci E, Wolk A. Folate intake, MTHFR polymorphisms, and risk of esophageal, gastric, and pancreatic cancer: A meta-analysis. Gastroenterology. 2006;131:1271-1283.

Larsson SC, Giovannucci E, Wolk A. A prospective study of dietary folate intake and risk of colorectal cancer: modification by caffeine intake and cigarette smoking. Cancer Epidemiol Biomarkers Prev. 2005;14(3):740-743.

Laurence KM, James N, Miller MH, Tennant GB, Campbell H. Double-blind randomised controlled trial of folate treatment before conception to prevent recurrence of neural-tube defects.
Br Med J (Clin Res Ed). 1981;282(6275):1509-1511.

Lawrence JM, Petitti DB, Watkins M, Umekubo MA. Trends in serum folate after food fortification. Lancet. 1999;354(9182):915-916.

Lawrence JM, Watkins ML, Chiu V, Erickson JD, Petitti DB. Food fortification with folic acid and rate of multiple births, 1994-2000. Birth Defects Res A Clin Mol Teratol. 2004;70(12):948-952.

Lee JE, Willett WC, Fuchs CS, et al. Folate intake and risk of colorectal cancer and adenoma: modification by time. Am J Clin Nutr. 2011;93(4):817-25.

Lee M, Hong K, Chang S, Saver JL. Efficacy of homocysteine-lowering therapy with folic acid in stroke prevention: a meta analysis. Stroke. 2010;41:1205-1212.

Li DK, Daling JR, Mueller BA, Hickok DE, Fantel AG, Weiss NS. Periconceptional multivitamin use in relation to the risk of congenital urinary tract anomalies. Epidemiology. 1995;6(3):212-218.

Li MM, Yu JT, Wang HF, et al. Efficacy of vitamins B supplementation on mild cognitive impairment and Alzheimer's disease: a systematic review and meta-analysis. Curr Alzheimer Res. 2014;11(9):844-852.

Li Z, Gindler J, Wang H, et al. Folic acid supplements during early pregnancy and likelihood of multiple births: a population-based cohort study. Lancet. 2003;361(9355):380-384.

Liu M, Cui LH, Ma AG, Li N, Piao JM. Lack of effects of dietary folate intake on risk of breast cancer: an updated meta-analysis of prospective studies. Asian Pac J Cancer Prev. 2014;15(5):2323-2328.

Liu S, Joseph KS, Luo W, et al. Effect of folic acid food fortification in Canada on congenital heart disease subtypes. Circulation. 2016a;134(9):647-655.

Liu X, Lv L, Zhang H, et al. Folic acid supplementation, dietary folate intake and risk of preterm birth in China. Eur J Nutr. 2016b;55(4):1411-1422.

Liu Y, Yu Q, Zhu Z, et al. Vitamin and multiple-vitamin supplement intake and incidence of colorectal cancer: a meta-analysis of cohort studies. Med Oncol. 2015;32(1):434. doi: 10.1007/s12032-014-0434-5.

Logan RF, Grainge MJ, Shepherd VC, Armitage NC, Muir KR, ukCAP Trial Group. Aspirin and folic acid for the prevention of recurrent colorectal adenomas. Gastroenterology. 2008;134(1):29-38.

Luchsinger JA, Tang MX, Shea S, Miller J, Green R, Mayeux R. Plasma homocysteine levels and risk of Alzheimer disease. Neurology. 2004;62(11):1972-1976.

Lucock M and Yates Z. Folic acid fortification: a double-edged sword. Curr Opin Clin Nutr Metab Care. 2009;12:555-564.

Malaguarnera M, Ferri R, Bella R, Alagona G, Carnemolla A, Pennisi G. Homocysteine, vitamin B12 and folate in vascular dementia and in Alzheimer disease. Clin Chem Lab Med. 2004;42(9):1032-1035.

Marti-Carvajal A, Sola I, Lathyris D, Salanti G.  Homocysteine lowering interventions for preventing cardiovascular events. Cochrane Database of Syst Rev. 2009 (4):CD006612.

Martí-Carvajal AJ, Solà I, Lathyris D. Homocysteine-lowering interventions for preventing cardiovascular events. Cochrane Database Syst Rev. 2015;1:CD006612.

Mason, JB. Folate, cancer risk, and the Greek god, Proteus: a tale of two chameleons. Nut Rev. 2009;67(4):206-212.

Mason JB, Dickstein A, Jacques PF, et al. A temporal association between folic acid fortification and an increase in colorectal cancer rates may be illuminating important biological principles: a hypothesis. Cancer Epidemiol Biomarkers Prev. 2007;16(7):1325-1329.

Mason JB, Tang SY. Folate status and colorectal cancer risk: A 2016 update. Mol Aspects Med. 2017;53:73-79.

Mathews F, Murphy M, Wald NJ, Hackshaw A. Twinning and folic acid use. Lancet. 1999;353(9149):291-292.

McLean R, Jacques P, Selhub J, et al. Plasma B vitamins, homocysteine, and their relation with bone loss and hip fracture in elderly men and women. J Clin Endocrinol Metab. 2008;93(6):2206-2212.

McLean RR, Jacques PF, Selhub J, et al. Homocysteine as a predictive factor for hip fracture in older persons. N Engl J Med. 2004;350(20):2042-2049.

Mei Q, Zhou D, Gao J, et al. The association between MTHFR 677C>T polymorphism and cervical cancer: evidence from a meta-analysis. BMC Cancer. 2012;12:467. doi: 10.1186/1471-2407-12-467.

Miller ER, Juraschek ZS, Pastor-Barriuso R, Bazzano L, Appel L, Guallar E. Meta-analysis of Folic Acid Supplementation Trials on Risk of Cardiovascular Disease and Risk Interaction with Baseline Homocysteine Levels. Am J Cardiol. 2010;106:517-527.

Mills JL, Rhoads GG, Simpson JL, et al. The absence of a relation between the periconceptional use of vitamins and neural-tube defects. National Institute of Child Health and Human Development Neural Tube Defects Study Group. N Engl J Med. 1989;321(7):430-435.

Mills JL, Signore C. Neural tube defect rates before and after food fortification with folic acid. Birth Defects Res A Clin Mol Teratol. 2004;70(11):844-845.

Milunsky A, Jick H, Jick SS, et al. Multivitamin/folic acid supplementation in early pregnancy reduces the prevalence of neural tube defects. JAMA. 1989;262(20):2847-2852.

Morris MS, Fava M, Jacques PF, Selhub J, Rosenberg IH.  Depression and folate status in the US Population. Psychother Psychosom. 2003;72(2):80-87.

MRC Vitamin Study Research Group. Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. MRC Vitamin Study Research Group. Lancet. 1991;338(8760):131-137.

Muggli EE, Halliday JL. Folic acid and risk of twinning: a systematic review of the recent literature, July 1994 to July 2006. Med J Aust. 2007;186(5):243-248.

Mulinare J, Cordero JF, Erickson JD, Berry RJ. Periconceptional use of multivitamins and the occurrence of neural tube defects. JAMA. 1988;260(21):3141-3145.

Nazer JH, Cifuentes LO. Effects of wheat flour fortification with folic acid on the prevalence of neural tube defects in Chile. Rev Med Chile. 2013;141(6):751-757.

Nelen WL, Blom HJ, Steegers EA, den Heijer M, Thomas CM, Eskes TK. Homocysteine and folate levels as risk factors for recurrent early pregnancy loss. Obstet Gynecol. 2000;95(4):519-524.

Ntaios G, Savopoulos C, Grekas D, Hatzitolios A. The controversial role of B-vitamins in cardiovascular risk: An update. Arch Cardiovasc Dis. 2009;(102):847-854.

Oaks BM, Dodd KW, Meinhold CL, Jiao L, Church TR, Stolzenberg-Solomon RZ. Folate intake, post-folic acid grain fortification, and pancreatic cancer risk in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Am J Clin Nutr. 2010;91:449-455.

Postiglione A, Milan G, Ruocco A, Gallotta G, Guiotto G, Di Minno G. Plasma folate, vitamin B(12), and total homocysteine and homozygosity for the C677T mutation of the 5,10-methylene tetrahydrofolate reductase gene in patients with Alzheimer's dementia. A case-control study. Gerontology. 2001;47(6):324-329.

Qin T, Du M, Du H, Shu Y, Wang M, Zhu L. Folic acid supplements and colorectal cancer risk: meta-analysis of randomized controlled trials. Sci Rep. 2015;5:12044. doi: 10.1038/srep12044.

Qin X, Xu M, Zhang Y, et al. Effect of folic acid supplementation on the progression of carotid intima-media thickness: A meta-analysis of randomized control trials. Atherosclerosis. 2012;222(2):307-313.

Quadri P, Fragiacomo C, Pezzati R, et al. Homocysteine, folate, and vitamin B-12 in mild cognitive impairment, Alzheimer disease, and vascular dementia. Am J Clin Nutr. 2004;80(1):114-122.

Ramos MI, Allen LH, Haan MN, Green R, Miller JW. Plasma folate concentrations are associated with depressive symptoms in elderly Latina women despite folic acid fortification. Am J Clin Nutr. 2004;80(4):1024-1028.

Rampersaud GC, Kauwell GP, Hutson AD, Cerda JJ, Bailey LB. Genomic DNA methylation decreases in response to moderate folate depletion in elderly women. Am J Clin Nutr. 2000;72(4):998-1003.

Ray JG, Meier C, Vermeulen MJ, Wyatt PR, Cole DE. Association between folic acid food fortification and congenital orofacial clefts. J Pediatr. 2003;143(6):805-807.

Refsum H, Ueland PM, Nygard O, Vollset SE. Homocysteine and cardiovascular disease. Annu Rev Med. 1998;49:31-62.

Renvall MJ, Spindler AA, Ramsdell JW, Paskvan M. Nutritional status of free-living Alzheimer's patients. Am J Med Sci. 1989;298(1):20-27.

Riddell LJ, Chisholm A, Williams S, Mann JI. Dietary strategies for lowering homocysteine concentrations. Am J Clin Nutr. 2000;71(6):1448-1454.

Rimm EB, Willett WC, Hu FB, et al. Folate and vitamin B6 from diet and supplements in relation to risk of coronary heart disease among women. JAMA. 1998;279(5):359-364.

Rohan TE, Jain MG, Howe GR, Miller AB. Dietary folate consumption and breast cancer risk. J Natl Cancer Inst. 2000;92(3):266-269.

Ronnenberg AG, Goldman MB, Chen D, et al. Preconception homocysteine and B vitamin status and birth outcomes in Chinese women. Am J Clin Nutr. 2002;76(6):1385-1391.

Rosche J, Uhlmann C, Froscher W. Low serum folate levels as a risk factor for depressive mood in patients with chronic epilepsy. J Neuropsychiatry Clin Neurosci. 2003;15(1):64-66.

Ruan J, Gong X, Kong J, Wang H, Zheng X, Chen T. Effect of B vitamin (folate, B6, and B12) supplementation on osteoporotic fracture and bone turnover markers: a meta-analysis. Med Sci Monit. 2015;21:875-881.

Saccone G, Berghella V. Folic acid supplementation in pregnancy to prevent preterm birth: a systematic review and meta-analysis of randomized controlled trials. Eur J Obstet Gynecol Reprod Biol. 2016;199:76-81.

Sanjoaquin MA, Allen N. Cuoto E, Roddam AW, Key TJ. Folate intake and colorectal cancer risk: A meta-analytical approach. Int J Cancer. 2005;113(5):825-828

Saposnik G, Ray JG, Sheridan P, McQueen M, Lonn E; Heart Outcomes Prevention Evaluation 2 Investigators. Homocysteine-lowering therapy and stroke risk, severity, and disability: additional findings from the HOPE 2 trial. Stroke. 2009;40(4):1365-1372.

Sarris J, Murphy J, Mischoulon D, et al. Adjunctive nutraceuticals for depression: a systematic review and meta-analyses. Am J Psychiatry. 2016;173(6):575-587.

Scanlon KS, Ferencz C, Loffredo CA, et al. Preconceptional folate intake and malformations of the cardiac outflow tract. Baltimore-Washington Infant Study Group. Epidemiology. 1998;9(1):95-98.

Schafer JH, Glass TA, Bolla KI, Mintz M, Jedlicka AE, Schwartz BS. Homocysteine and cognitive function in a population-based study of older adults. J Am Geriatr Soc. 2005;53(3):381-388.

Scholl TO, Hediger ML, Schall JI, Khoo CS, Fischer RL. Dietary and serum folate: their influence on the outcome of pregnancy. Am J Clin Nutr. 1996;63(4):520-525.

Selhub J, Jacques PF, Wilson PW, Rush D, Rosenberg IH. Vitamin status and intake as primary determinants of homocysteinemia in an elderly population. JAMA. 1993;270(22):2693-2698.

Sellers TA, Grabrick DM, Vierkant RA, et al. Does folate intake decrease risk of postmenopausal breast cancer among women with a family history? Cancer Causes Control. 2004;15(2):113-120.

Seshadri S, Beiser A, Selhub J, et al. Plasma homocysteine as a risk factor for dementia and Alzheimer's disease. N Engl J Med. 2002;346(7):476-483.

Setién-Suero E, Suárez-Pinilla M, Suárez-Pinilla P, Crespo-Facorro B, Ayesa-Arriola R. Homocysteine and cognition: A systematic review of 111 studies. Neurosci Biobehav Rev. 2016;69:280-298.

Shaw GM, Carmichael SL, Nelson V, Selvin S, Schaffer DM. Food fortification with folic acid and twinning among California infants. Am J Med Genet. 2003;119A(2):137-140.

Shaw GM, Carmichael SL, Nelson V, Selvin S, Schaffer DM. Occurrence of low birthweight and preterm delivery among California infants before and after compulsory food fortification with folic acid. Public Health Rep. 2004;119(2):170-173.

Shaw GM, Lammer EJ, Wasserman CR, O'Malley CD, Tolarova MM. Risks of orofacial clefts in children born to women using multivitamins containing folic acid periconceptionally. Lancet. 1995;346(8972):393-396.

Shaw GM, O'Malley CD, Wasserman CR, Tolarova MM, Lammer EJ. Maternal periconceptional use of multivitamins and reduced risk for conotruncal heart defects and limb deficiencies among offspring. Am J Med Genet. 1995;59(4):536-545.

Shen L, Ji HF. Associations between homocysteine, folic acid, vitamin B12 and Alzheimer's Disease: insights from meta-analyses. J Alzheimers Dis. 2015;46(3):777-790.

Siega-Riz AM, Savitz DA, Zeisel SH, Thorp JM, Herring A. Second trimester folate status and preterm birth. Am J Obstet Gynecol. 2004;191(6):1851-1857.

Signore C, Mills JL, Cox C, Trumble AC. Effects of folic acid fortification on twin gestation rates. Obstet Gynecol. 2005;105:757-762.

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