Folate (Folic Acid)
Folate is one of the B vitamins. Also known as vitamin B9, folate is essential for the production of red and white blood cells, and the conversion of food into useable energy. Folate also plays an integral role in producing DNA and RNA. Adequate amounts of folate are necessary especially during pregnancy. Folate is found in most foods such as broccoli, brussels sprouts, cabbage, kale, spinach, and breakfast cereals. When taken as supplements, it is available as folic acid which is the manmade version of folate.
Overall Health Benefits
- Maintains Healthy Pregnancy [1-7]
- Prevents Cardiovascular Disease [8-13]
- Lowers Risk of Stroke [14-18]
- Treats Depression and Improves Mood [19-22]
- Prevents Vision Loss [23-24]
- Prevents Cognitive Decline [25-29]
- Treats Anemia [30-40]
Proven Health Benefits
Maintains Healthy Pregnancy
A convincing number of studies suggest that folate and folic acid are essential for a healthy pregnancy:
- Studies showed that early supplementation of folate on reproductive-aged women is essential to prevent complications for both the mother and the fetus during pregnancy.
- Clinical studies showed that folate supplementation during pregnancy was effective in preventing birth defects. [2-4]
- In infertile Swedish women, folate supplementation resulted in higher pregnancy rate. 
- Studies showed that folate supplementation in infertile women increased the chance of being pregnant. 
- Studies showed that folate supplementation was associated with a reduced risk of infertility and pregnancy loss. 
Prevents Cardiovascular Disease
The cardioprotective effects of folate and folic acid are also backed by a number of studies:
- A study showed that folate supplementation dramatically decreased the risk of death in patients with cardiovascular disease (CVD). 
- A study also showed that folate supplementation was associated with a decreased risk of CVD. 
- Folic acid was found to be effective in lowering homocysteine concentrations; high levels of homocysteine were associated with an early development of cardiovascular disease. [10-13]
Lowers Risk of Stroke
Evidence suggests that folate and folic acid can also protect against stroke:
- A study suggested that folate supplementation has beneficial effects on stroke prevention. 
- Clinical trials showed that folate supplementation can help lower stroke risk. 
- In patients with CVD, folic acid administration resulted in lower risk of stroke. 
- In male patients, folate supplementation lowered stroke risk. 
- Long-term supplementation with folic acid reduced the risk of stroke by 10%, which may be due to folic acid’s role in lowering homocysteine concentrations. 
Treats Depression and Improves Mood
A good deal of evidence shows that folate and folic acid have mood-enhancing effects:
- A study found that high concentrations of folate can relieve symptoms of depression. 
- In depressed patients, a combination of folate administration and standard therapy produced positive effects on symptom of depression. 
- Studies showed that folic acid deficiency were associated with a higher risk of depression. [21-22]
Prevents Vision Loss
Studies also found that folate and folic acid can help improve eye function and prevent vision problems:
- In a study conducted among the smoker and alcoholic patients who had poor vision, oral intake of folic acid significantly improved their vision. 
- In animal models, regular supplementation with folate resulted in fast recovery of eye function. 
Prevents Cognitive Decline
Folate and folic acid have also been shown to boost cognitive function and prevent age-related cognitive decline:
- A study reported that folic acid can help improve brain function by reducing the levels of homocysteine. 
- A study showed that folate administration improved cognitive function in patients with mild cognitive impairment. 
- In elderly Chinese with mild cognitive impairment, oral administration of folate resulted in great improvement in brain performance. 
- In patients with mild cognitive impairment, folic acid supplementation boosted their brain function. 
- In older individuals, high folate concentrations were associated with a reduced risk of brain disease. 
Studies show that folate and folic acid can help protect against different types of anemia (low red blood cells):
- Studies showed that folate deficiency was associated with a higher risk of anemia. [30-38]
- When combined with iron, folate can significantly reduce the risk of pregnancy-associated anemia. 
- In older adults, folic acid supplementation reduced the prevalence of folate-deficiency anemia. 
- Greenberg JA, Bell SJ, Guan Y, Yu YH. Folic Acid supplementation and pregnancy: more than just neural tube defect prevention. Rev Obstet Gynecol. 2011;4(2):52-59.
- Available at https://jbiomedsci.biomedcentral.com/articles/10.1186/s12929-014-0077-z.
- Honein M. et al. Impact of folic acid fortification of the US food supply on the occurrence of neural tube defects. JAMA; 285(23) 2981-2986.
- Berry R. et al. 1999. Prevention of Neural-Tube Defects with Folic Acid in China. New England Journal of Medicine; 341, 1485-1490.
- Murto T, Yngve A, Skoog Svanberg A, et al. Compliance to the recommended use of folic acid supplements for women in Sweden is higher among those under treatment for infertility than among fertile controls and is also related to socioeconomic status and lifestyle. Food Nutr Res. 2017;61(1):1334483. Published 2017 Jun 9. doi:10.1080/16546628.2017.1334483.
- Schaefer E, Nock D. The Impact of Preconceptional Multiple-Micronutrient Supplementation on Female Fertility. Clin Med Insights Womens Health. 2019;12:1179562X19843868. Published 2019 Apr 23. doi:10.1177/1179562X19843868.
- Gaskins AJ, Chavarro JE. Diet and fertility: a review. Am J Obstet Gynecol. 2018;218(4):379-389. doi:10.1016/j.ajog.2017.08.010.
- Lonn E. et al. 2006. Homocysteine lowering with folic acid and B vitamins in vascular disease. The New England Journal of Medicine; 354 (15) 1567-1577.
- Malinow M. et al. 1998. Reduction of Plasma Homocyst(e)ine Levels by Breakfast Cereal Fortified with Folic Acid in Patients with Coronary Heart Disease. New England Journal of Medicine; 338, 1009-1015
- Collaboration HLT. Lowering blood homocysteine with folic acid based supplements: meta-analysis of randomised trials. BMJ : British Medical Journal. 1998;316(7135):894-898.
- Wang Y, Jin Y, Wang Y, Li L, Liao Y, Zhang Y, Yu D. The effect of folic acid in patients with cardiovascular disease: A systematic review and meta-analysis. Medicine (Baltimore). 2019 Sep;98(37):e17095. doi: 10.1097/MD.0000000000017095. PMID: 31517834; PMCID: PMC6750242.
- Li Y, Huang T, Zheng Y, Muka T, Troup J, Hu FB. Folic Acid Supplementation and the Risk of Cardiovascular Diseases: A Meta-Analysis of Randomized Controlled Trials. J Am Heart Assoc. 2016 Aug 15;5(8):e003768. doi: 10.1161/JAHA.116.003768. PMID: 27528407; PMCID: PMC5015297.
- Yang HT, Lee M, Hong KS, Ovbiagele B, Saver JL. Efficacy of folic acid supplementation in cardiovascular disease prevention: an updated meta-analysis of randomized controlled trials. Eur J Intern Med. 2012 Dec;23(8):745-54. doi: 10.1016/j.ejim.2012.07.004. Epub 2012 Aug 11. PMID: 22884409.
- Hsu CY, Chiu SW, Hong KS, et al. Folic Acid in Stroke Prevention in Countries without Mandatory Folic Acid Food Fortification: A Meta-Analysis of Randomized Controlled Trials. J Stroke. 2018;20(1):99-109. doi:10.5853/jos.2017.01522.
- Tian T, Yang KQ, Cui JG, Zhou LL, Zhou XL. Folic Acid Supplementation for Stroke Prevention in Patients With Cardiovascular Disease. Am J Med Sci. 2017 Oct;354(4):379-387. doi: 10.1016/j.amjms.2017.05.020. PMID: 29078842.
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- Elisa Santandrea, Ilaria Sani, Gianpaolo Morbioli, Domenico Multari, Giorgio Marchini, Leonardo Chelazzi; Optic Nerve Degeneration and Reduced Contrast Sensitivity Due to Folic Acid Deficiency: A Behavioral and Electrophysiological Study in Rhesus Monkeys. Invest. Ophthalmol. Vis. Sci. 2018;59(15):6045-6056. doi: https://doi.org/10.1167/iovs.18-24822.
- Vijayakumar A, Kim EK, Kim H, Choi YJ, Huh KB, Chang N. Effects of folic acid supplementation on serum homocysteine levels, lipid profiles, and vascular parameters in post-menopausal Korean women with type 2 diabetes mellitus. Nutr Res Pract. 2017;11(4):327-333. doi:10.4162/nrp.2017.11.4.327.
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- Ma F, Wu T, Zhao J, et al. Folic acid supplementation improves cognitive function by reducing the levels of peripheral inflammatory cytokines in elderly Chinese subjects with MCI. Sci Rep. 2016;6:37486. Published 2016 Nov 23. doi:10.1038/srep37486.
- Ma F, Li Q, Zhou X, Zhao J, Song A, Li W, Liu H, Xu W, Huang G. Effects of folic acid supplementation on cognitive function and Aβ-related biomarkers in mild cognitive impairment: a randomized controlled trial. Eur J Nutr. 2019 Feb;58(1):345-356. doi: 10.1007/s00394-017-1598-5. Epub 2017 Dec 18. PMID: 29255930.
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