Folate Supplementation, Pregnancy and Fetal Development

The Importance of Folate in Fetal Development

Getting plenty of folate (also known as vitamin B9 or Pteroylglutamic acid) is thought to be essential for pregnant women, both before and after conception. This is due to the fact that folate (the naturally occurring form of the vitamin that’s commonly found in food) is absolutely crucial for fetal development whereas the body requires a high folate intake to support the process of pregnancy. 

For this reason, medical professionals advise that women who are planning to conceive should supplement with folic acid (the synthetic version that’s commonly added to supplements and fortified foods). In fact, supplementing with folic acid prior to conception and during the first trimester is estimated to reduce the fetus’s risk of developing neural tube defects, a category of sometimes serious or even fatal birth defects, by 40 to 80 percent.

For this same reason, since 1998, the United States government has mandated that certain standardized foods (e.g., wheat flour) must be fortified with folic acid to reduce instances of folate deficiency that often results in birth defects.

Potential Risks of Folate Deficiency in Pregnancy

Folate deficiency is one of the most harmful nutrient deficiencies for pregnant women and their developing fetuses. A folate deficiency is thought to have the ability to cause several pregnancy complications that can be severe.

Since folate is essential for the natural development of the neural tube, a lack of folate before and during pregnancy may result in birth defects known as neural tube defects. These defects can include anencephaly, when a baby is born with missing parts of the brain and skull, and spina bifida, which involves incomplete development of the spine, and can range from quite mild and asymptomatic to severe and causing significant nerve damage.

Being folate deficient while pregnant may also raise the risk of developing placental abruption, which occurs when the placenta separates from the uterus, as well as possibly prompting premature birth and low birth weight. Some studies suggest that folate deficiency during pregnancy may also increase the risk of autism.

Recommended Folate Intake During Pregnancy

While the daily recommended dose of folic acid for most adults is 400 micrograms, adult women who are planning to get pregnant or believe they may get pregnant should most likely consume 400 to 1,000 micrograms of folic acid per day from foods and supplements. It is also thought that breastfeeding women should also make sure to get plenty of folate, at similar doses per day.

When to Start Folate Supplementation

For those who are planning to get pregnant, it is essential to begin supplementing with folic acid not only during the first trimester of pregnancy, but also before getting pregnant. Research shows that the risk of neural tube defects is much lower for mothers who supplement with folic acid starting one month before conception and continue to do so for two to three months following conception. 

This is thought to be since folate and folic acid may only do its job to prevent birth defects during the first few weeks of pregnancy, after which point it may be too late to reverse many of the negative effects of folate deficiency. More specifically, as the fetus develops, the neural tube (which eventually becomes the brain and spinal cord) is among the first body structures to begin forming. If the pregnant mother has a folate deficiency, the neural tube may be unable to form properly, which may lead to birth defects such as spina bifida and anencephaly.

Folate vs. Folic Acid

Comparing the Two Compounds

Although folate and folic acid are both forms of vitamin B9 and share a similar name (both come from the Latin root word “folium,” meaning leaf) these two terms refer to similar but distinct substances. 

Folate is a broader term, describing vitamin B9 as it occurs in nature, such as in foods such as fruits, nuts, dairy, beans, grains, liver, brewer’s yeast, sprouts, and green leafy vegetables. In the body, the digestive process may turn the majority of this folate into 5-methyltetrahydrofolate (5-MTHF), the more bioavailable version of vitamin B9 that the body may use for various functions.

In contrast, folic acid is one of several distinct types of folates. Folic acid does not occur in nature, and must be synthesized by humans, so it is often described as synthetic. Other terms for this form of vitamin B9 include monopteroylglutamic acid and pteroylmonoglutamic acid. Folic acid is the type of folate that is most often found in fortified foods (e.g., wheat flour, rice, breakfast cereals, etc.) as well as vitamin supplements.

Which Is Better?

Although folic acid is a type of folate, folic acid metabolism in the body is less efficient than metabolism of other forms of folate. This is because folic acid is more challenging for the body to break down and utilize than other forms, such as 5-MTHF. 

As a result, the digestive system converts some of the folic acid that we consume into 5-MTHF, but the remainder may only be metabolized through the liver. Some people have genetic mutations that make it more difficult for their livers to transform folic acid into 5-MTHF. This means that when these people take folic acid supplements, the unconverted folic acid can build up in their bloodstreams over time and potentially increase risk of serious health conditions and diseases such as cancer. Research into the long-term effects of unmetabolized folic acid buildup is ongoing, but so far, it suggests that this state may be seriously harmful to one’s health.

Although genetic differences in folic acid metabolism mean that folic acid may be more harmful for some than for others, it is thought to be reasonable to state that supplementing with a more bioavailable form of folate (e.g., 5-MTHF) would provide more benefits for most people than folic acid supplementation.

5-MTHF Folate Supplementation

Although folate is found in a range of foods, it can be challenging to consume enough of this essential nutrient exclusively through diet. The folate found in food is also relatively unstable, which means that it is easily oxidized via exposure to light, heat, and metal ions, and as a result, cooking may actually make dietary folate less bioavailable.

Folate supplementation may bridge the gap between daily folate needs and intake, especially for those who are pregnant. A 5-MTHF supplement is especially beneficial to pregnant women, since this form of the nutrient may be much easier for the body to break down and utilize. This is especially true for those with genetic mutations that make their bodies less able to metabolize folate efficiently. 

Speak to a Doctor Before Adding a Folate Supplement

Taking a 5-folate supplement is thought to be safe for the majority of healthy people, but those with certain conditions should avoid supplementing with folate. 

For instance, folic acid supplementation should be avoided in those recovering from angioplasty, since it may contribute to narrowing of the arteries. In addition, some research shows that folic acid supplementation at 0.8 to 1 mg per day may increase cancer risk, so those with a history of cancer should not take high doses of this nutrient. Folic acid supplementation may also worsen symptoms of seizure disorders and obscure vitamin B12 deficiency, to the point that it may cause nerve damage. Folic Acid supplements may also interact with certain medications, including anticonvulsants, barbiturates, methotrexate (a medication that treats cancer, as well as other ailments), and pyrimethamine (an antimalarial drug). 

Since folate supplementation is not a good fit for every person’s medical situation, it is important to speak with a medical professional who is familiar with your unique medical background to confirm that it is a safe choice for your needs before beginning to take folate.