Pregnant friends enjoying healthy sandwiches

Can Folic Acid Fortified Bread Prevent Birth Defects?

Can Folic Acid Fortified Bread Prevent Birth Defects?

Scientifically reviewed by: Michael A. Smith, MD

For many eager moms-to-be, taking a prenatal vitamin with folic acid is a no-brainer; this form of vitamin B9 is well-known for its ability to prevent spina bifida, anencephaly and other serious birth defects. But what about when a pregnancy is unplanned or a mother isn't aware of the importance of folate in preventing neural tube defects, or NTDs?

The United Kingdom announced a plan last year to fortify a popular type of flour with folic acid—with the hopes that keeping neural tube defects at bay would be as simple as eating toast for breakfast. The move would align the UK with many others—including the United States, which has been fortifying enriched grain products for over 20 years, significantly reducing the prevalence of neural tube defects in the U.S.

Unfortunately, a new paper written by an expert in folate deficiency suggests that the UK's new folic acid fortified flour would only prevent 10% of neural tube defects at proposed levels. Sir Nicholas Wald, a professor of preventive medicine at University College London, wrote in the Journal of Medical Screening that a mandatory folic acid fortification policy that matches clinically studied amounts of folic acid, 4 mg daily, is needed.

"The fortification level should be sufficient to safely achieve the full preventive effect," he wrote, calling for a level that is "optimal not partial."

What are neural tube birth defects?

Neural tube defects occur in early pregnancy when the baby's neural tube doesn't close or develop properly. Unfortunately for expecting parents, these neural tube defects often cause miscarriage, stillbirths and infant deaths. The most common of these birth defects are spina bifida and anencephaly. Nerve damage and other disabilities, such as inability to walk and digestive and urinary problems, can result from spina bifida, while anencephaly is fatal since it results in the lack of development of a brain or skill.

Neural tube defects are fairly common—with about 300,000 cases yearly worldwide. Depending on the region, NTD rates range from about five per 10,000 on the low end to 100 per 10,000 on the high end.

What is folic acid?

Folic acid is a form of vitamin B9, just like folate, which is the same B vitamin in food form. Folate naturally occurs in foods such as asparagus, broccoli, banana, avocado, wheat germ, kidney beans and green leafy vegetables. Folic acid, on the other hand, is a synthetic form added to processed foods, such as fortified enriched wheat, pasta, rice and breakfast cereals.

There is an advantage to folic acid, because it is generally more bioavailable than the folates found in food. This means your body is absorbing more of the vitamin B9 in your enriched cereal and toast than the B9 in your avocado.

And getting enough folate is essential, because this B vitamin is key to many processes in the body. During pregnancy, it helps to form and properly close the neural tube, or the early brain and spinal cord, of a fetus. This is why folate is so important for mothers in early pregnancy—not having enough can have devastating results for their babies.

The author of the recent paper, Professor Wald, led the groundbreaking MRC Vitamin Study, published in 1991, that determined that neural tube defects, or NTDs, were caused by a folate deficiency. "The results of the trial were so clear-cut that the trial was stopped early," Wald wrote. "Among women allocated to receive capsules containing folic acid, the NTD rate was much reduced, by 71%, compared to the rate among women allocated capsules without the vitamin." The NTD rate was reduced even more—up to 83%—for women who took 4 mg of folic acid before conception and kept taking it into pregnancy, the study found.

After the MRC Vitamin Study was published, health authorities worldwide began advising folate intake for women of reproductive age. They recommended that women increase folic acid intake even before they attempt to conceive a child and continue taking it for the first three months of pregnancy. The timing is important because neural tube closure, which folate supports, happens about four weeks after conception—before many women even know they are pregnant.

Why does folic acid prevent birth defects?

Although studies have proven the link between neural tube defects and vitamin B9 folate deficiency, the mechanism by which folate acts on NTDs remains largely unknown. What we do know is that when the baby is developing during early pregnancy, folate and folic acid help form the neural tube, and in general, folate is essential for making new cells. Studies suggest that in addition to folate intake, folate receptors (which get the vitamin into cells) are also key to healthy neural tube closure.

Although food fortification and increase folic acid intake has helped reduce the rate of neural tube defects such as spina bifida and anencephaly—in which the brain and sometimes parts of the skull fail to develop—these birth defects still occur.

Which folic acid is best?

It is essential that anyone considering pregnancy take folic acid in addition to getting folate from their diet. According to the CDC, it is best to start folate intake 5-6 months before conceiving to allow folate levels time to build to optimal strength.

Some people have a hard time metabolizing folic acid (particularly people with a certain mutation called MTHFR), so taking a metabolized form of folate, such as L-methylfolate, is recommended.

Folic acid dosage recommendations

Although the MRC Vitamin Study used a folic acid dose of 4 mg daily, current recommendations are much lower, much to the chagrin of Professor Wald. "The advice should have been to recommend 4 mg/day for all women who could become pregnant. The regulatory authorities such as the Medicines and Healthcare Products Regulatory Agency (MHRA) in the UK and the Food and Drug Administration (FDA) in the USA should revise the advice given," he wrote.

His recent article also argues against the "token" mandatory folic acid fortification proposed in the UK. "It should not be acceptable to adopt a policy designed to prevent 20% of NTDs when 80% could be safely prevented simply by increasing the fortification level and the range of staple foods that are fortified," he wrote. "There is no practical or moral justification for rejecting a more effective version of fortification in favor of a less effective version." Most prenatal vitamins have 400 mcg (micrograms) of folic acid.

This is far less than the clinically studied amount of folic acid for preventing neural tube defects, considering 1,000 micrograms makes up 1 mg.

Many experts recommend higher doses of folate before and during pregnancy. "All the evidence taken together shows that the full NTD-preventable effect would be achieved if folic acid fortification were set at a level and in a range of foods that would increase average folic acid intake by 4 mg per day," Wald wrote. "This is the safe, inexpensive and equitable policy of choice. Unlike current policies, nearly all NTDs would be prevented."

Top nutrients for pregnancy

Because pregnant women are growing a whole new human inside their bodies, all nutrients in their diet are important during this time. But several play a key role in a baby's growth and development, including:

Ensuring optimum levels of these nutrients can help protect against birth defects, premature birth and nutritional deficiencies, which benefits both the baby and the mother. After all, if you don't get enough calcium during pregnancy, your body takes it from your bones for your baby's growth. This can cause serious health issues, such as osteoporosis, for mothers later in life. Other nutrients, such as probiotics, can help with both digestion and morning sickness during pregnancy.

How to choose a high-quality prenatal

When looking for a prenatal multivitamin, folic acid is obviously a priority in preventing birth defects and NTD pregnancies. But the best multivitamin will provide a wide range of vitamins, nutrients and minerals.

Pregnant mothers will want to provide their babies with everything they need, including nutrients not commonly found in a prenatal vitamins, such as:

  • DHA, which is needed for fetal neurodevelopment
  • Iron to protect against iron deficiency anemia
  • Choline, which also supports neural tube development

Before starting prenatal vitamins or folic acid, talk to your doctor to decide on a form and dose that is best for you, which may depend on your MTHFR status, your risk for NTDs, or other factors.



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The Life Extension Health News team delivers accurate information about vitamins, nutrition and aging. Our stories rely on multiple, authoritative sources and experts. We keep our content accurate and trustworthy, by submitting it to a medical reviewer.