Distributions include background intake from natural food folate and voluntary folic acid fortification. Almost identical distributions are obtained using the usual intake of folate in the USA from the Continuing Survey of Food Intakes by Individuals [ 21 ]. Intake from mandatory folic acid fortification assumed to be independent of natural food folate and folic acid from voluntary fortification but with the same population variance]. Figure 6 shows the distributions of folic acid intake in contrast to folate intake shown in Fig.
The figure focuses on folic acid because the misplaced concern over possible toxicity which led to an upper intake limit being set relates to folic acid intake, not natural food folate intake, although, illogically, in setting the upper limit, the two were combined. The figure shows that taking a daily 0. Distributions of folic acid FA intake with voluntary and mandatory fortification with and without 0.
Intake from mandatory folic acid fortification assumed to be independent of natural food folate and folic acid from voluntary fortification but with the same population variance. Folic acid supplement assumed to be taken every day.
Figures 5 and 6 illustrate how mandatory fortification of flour with folic acid, so as to increase average intake to a level that protects the majority of women against NTDs, inevitably leads to a somewhat greater proportion of people exceeding the arbitrary 1 mg ceiling. As we have shown, the interpretation of the data used to set a UL for folic acid was flawed; a UL for folic acid is not needed and consequently the conflict of policies disappears.
A matter of public health concern is that some authorities, such as the European Commission Scientific Committee on Food, put greater weight on the hypothetical possibility of harm than on the proven evidence of benefit, apparently ignoring the fact that withholding a benefit is itself a harm.
The EU report does not cite the MRC Vitamin Study randomised trial which demonstrated the benefit of increasing folic acid intake, but focuses almost entirely on hypothetical harms. The EU report states:. As reasoned above, masking the diagnosis of B12 deficiency is an outdated concept if ever it was a useful one , and the contention that folic acid is neurotoxic is scientifically wrong. Neither should be the basis for determining policy on folic acid fortification.
To the extent that B12 deficiency is itself a public health concern [ 22 ] flour fortification should include B12 as well as folic acid, as has been done in the territory controlled by the Palestinian Authority. The correct public health policy message is simple: flour should be fortified with folic acid so that, on average, folic acid intake is increased by at least 0. The use of an upper intake level for folate should be abandoned. We suggest that there are grounds for the US Institute of Medicine to reconsider its opinion on this issue in the light of the evidence and reasons given in this paper.
Failure to fortify is more than a missed opportunity; it is a tragedy. Since , it has been estimated that there have been over five million preventable NTD pregnancies in the world [ 23 ]. The number of NTD pregnancies that could have been prevented by folic acid far exceeds the total number of cases of thalidomide induced phocomelia 10, [ 24 ]. While the thalidomide tragedy prompted immediate worldwide public health intervention, many countries still ignore the preventable toll of disability, stillbirth, infant death, and terminations of pregnancy caused by NTDs.
There is no scientific basis for setting an upper level of intake for folate. Having such a limit, which has been set at 1 mg per day, has acted as a barrier to the wider introduction of mandatory fortification of flour with folic acid to prevent neural tube defects.
For both reasons, the upper limit should be discarded. This would have the practical effect of leaving no scientific obstacle to the introduction of mandatory folic acid fortification in all countries, which would have an important global impact on the prevention of neural tube defects. Article Google Scholar. Wald NJ. Folic acid and the prevention of neural tube defects. Maternal nutrition and pregnancy outcome, vol. Tulchinsky TH.
Commentary: the key role of government in addressing the pandemic of micronutrient deficiency conditions in Southeast Asia. Prevention of neural tube defects: a cross-sectional study of the uptake of folic acid supplementation in nearly half a million women. PLoS One. Impact of folic acid fortification of the US food supply on the occurrence of neural tube defects. Hertrampf E, Cortes F. National food fortification program with folic acid in Chile. Food Nutr Bull.
Reduction in neural tube defects after folic acid fortification in Canada. New Engl J Med. European Commission Scientific Committee on Food. Opinion on the tolerable upper intake level of folate. Quantifying the effect of folic acid. Near elimination of folate deficiency anemia by mandatory folic acid fortification in older US adults: reasons for the geographic and racial differences in stroke study Am J Clin Nutr.
Prevalence of anemia in persons 65 years and older in the United States: evidence of a high rate of unexplained anemia. Review of the magnitude of folate and vitamin B12 deficiencies worldwide. Food and Nutr Bull. Institute of Medicine.
Food and Nutrition Board. Google Scholar. Scientific Advisory Committee on Nutrition. Update on Folic Acid. July Dickinson CJ. Does folic acid harm people with vitamin B12 deficiency? Q J Med. CAS Google Scholar. Neuropsychiatric disorders caused by Cobalamin deficiency in the absence of anemia or macrocttosis.
N Engl J Med. Bower C, Wald NJ. Vitamin B12 deficiency and the fortification of food with folic acid. Eur J Clin Nutr. If you are pregnant , having a high enough amount of folate in your blood blood folate concentration is important to help to prevent a neural tube defect in your developing baby. Blood folate concentration is the amount of folate that can be measured in your blood. Population red blood cell folate concentrations for prevention of neural tube defects: Bayesian model.
BMJ Clinical research ed. Reduction in neural-tube defects after folic acid fortification in Canada. The New England journal of medicine. Spina bifida before and after folic acid fortification in Canada. Birth defects research Part A, Clinical and molecular teratology. AE, Dudas I. Prevention of the first occurrence of neural-tube defects by periconceptional vitamin supplementation.
Prevention of neural-tube defects with folic acid in China. Lancet London, England. E, Selhub J. Properties of food folates determined by stability and susceptibility to intestinal pteroylpolyglutamate hydrolase action. The Journal of nutrition. Updated estimates of neural tube defects prevented by mandatory folic Acid fortification — United States, March of Dimes, a not-for-profit, section c 3. Privacy, Terms, and Notices , Cookie Settings. Register Sign In. Hi Your dashboard sign out.
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Saving Just a moment, please. You've saved this page It's been added to your dashboard. In This Topic. Folic acid helps prevent NTDs only if you take it before and in the first weeks of pregnancy. What are neural tube defects?
What causes NTDs? Are you at risk for having a baby with an NTD? To find out about your risk for NTDs, talk to a genetic counselor.
This means you have a family history of NTDs. Fill it out and share it with your health care provider or genetic counselor. Other risk factors for NTDs include: You take certain anti-seizure medicines.
If you take medicine to prevent seizures, talk to your health care provider before you get pregnant about how the medicine may affect your pregnancy. Some studies show that being obese increases your risk for having a baby with an NTD. To find out your BMI, go to cdc.
Talk to your provider about getting to a healthy weight before pregnancy. You have diabetes. Diabetes is a medical condition in which your body has too much sugar called glucose in your blood. This can damage organs in your body, including blood vessels, nerves, eyes and kidneys. If your diabetes is uncontrolled, you may be at increased risk for having a baby with an NTD.
You can help control diabetes by eating healthy foods and being active every day. You use opioids in the first 2 months of pregnancy. Opioids are highly addictive drugs. Common prescription opioids include codeine, hydrocodone and oxycodone. These often are sold and used illegally. If you take any opioid during pregnancy, it can cause serious problems for your baby, like premature birth and drug withdrawal called neonatal abstinence syndrome also called NAS. You have a high body temperature early in pregnancy.
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