Excess folic acid and pregnancy

Folic acid is the synthetic form of folate (vitamin B9). Folate is an essential vitamin that your body needs for cell and DNA formation. Particularly before conceiving and during the early stages of pregnancy, getting enough of this vitamin is vital. Folate deficiency can lead to anemia (not having enough healthy red blood cells) and pregnancy complications, including neural tube defects and miscarriage. But consuming too much folic acid from supplements and fortified foods can be harmful as well, particularly during pregnancy.

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Impact of excess folic acid on pregnancy

Research shows that excess folic acid during pregnancy is linked to impaired growth of the baby in the womb and a higher chance that the baby will develop insulin resistance, diabetes, asthma, and obesity later in life. Taking over 1,000 micrograms of folic acid in the months before and after conception may also slow brain development in children, one study shows.

Having extremely high levels of folic acid during pregnancy can also increase the child’s risk of developing autism. Excess folic acid combined with excess vitamin B12 increases this risk by 17.6 times.

Potential causes of excess folic acid

Excess folic acid comes from taking too many supplements with a very high dose of this vitamin and too many folic acid-fortified foods. It doesn’t happen when you eat foods that are naturally rich in folate. Genetics may also predispose somebody to absorb more folate from foods or metabolize it at a slower rate, which could lead to excess folic acid in the body.

Symptoms of excess folic acid

Taking a folic acid supplement dose of over 1,000 micrograms per day can cause the following side effects:

• Upset stomach
• Nausea
• Diarrhea
• Irritability
• Confusion
• Skin reactions
• Seizures

Excess folic acid may also increase the risk for serious health problems, including cancer and heart attack (in people already at a higher risk of heart disease).

Taking large amounts of folic acid supplements can also conceal a vitamin B12 deficiency and worsen symptoms of the deficiency. 

Diagnosis of excess folic acid

You can check your folic acid status with a blood test. Tell your doctor about any medications you are taking before the test, as some drugs can interfere with the results. If your test shows that you have very high amounts of folic acid in the blood, you will be diagnosed with excess folic acid.

Treatment

Work with your doctor to choose a prenatal supplement that’s right for your body to ensure that you have safe levels of folic acid before you conceive. Some women are recommended to take higher doses of folic acid supplements if they are at risk of having a pregnancy affected by neural tube defects. 

To decrease your folic acid intake, you should also check nutritional labels on foods you buy, as folic acid is added to many foods (cereals, flour, bread, pasta, baked goods, and crackers). Choose options that don’t have the vitamin added to them. Focus instead on getting your fill of folate from foods where it is found naturally. 

Folate-rich foods include: 

• Spinach
• Brussels sprouts
• Broccoli
• Asparagus
• Beans
• Peanuts
• Sunflower seeds
• Seafood
• Eggs
• Whole grains

You can meet with a LEVY nutritionist to create a personalized meal plan to make sure you meet your specific dietary needs to boost your fertility and chances of a healthy pregnancy and baby.

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