"Women need optimal amounts of folic acid during conception and early fetal development to reduce the chances of having a baby with neural tube defects," says Wahida Karmally, director of nutrition at the Irving Center for Clinical Research at Columbia University in New York.
Fad diets and unhealthy weight loss programs may also work against the developing baby. "My concern would be when women follow low-carbohydrate diets for weight reduction or management, their diets will be very deficient in several nutrients including folic acid," Karmally says.
Too Much Folic Acid?
Can you take too much folic acid?
"There doesn't appear to be a risk factor associated with high levels of folic acid intake, but we acknowledge that this is an important area for future research," says Honein.
Folic acid is a water-soluble vitamin that has no known toxicity, so any excess vitamin in your system simply leaves your body when you go to the bathroom.
But people over 50 should be careful about taking in high levels of folic acid. The vitamin can have negative effects on people with "pernicious anemia," a type of anemia that occurs mainly within the elderly.