Folic acid during pregnancy: You need to get the dosage right to avoid fetal brain changes

According to a new study, too much folic acid can be just as detrimental as too little for fetal health. Read on to know more.

A UC Davis MIND Institute study of pregnant mice found that high amounts of folic acid during pregnancy harmed the brain development of embryos. Researchers say the findings indicate that more investigation is needed about the best recommended dosage for pregnant women. They believe there's a Goldilocks effect with folic acid. Too little is not good, too much is not good; you have to get it just right. The study, published in Cerebral Cortex, involved pregnant mice who were given either a normal amount of folic acid, 10 times the recommended amount, or none. The offspring of the mice that received the largest amount showed significant brain changes.

Brain changes in fetus linked to folic acid deficiency, overdose

According to researchers, the brain damage is not subtle. It's substantial. It makes a marked difference in brain structure if you take very high amounts of folic acid. Paradoxically, changes in the brain due to too much folic acid mimicked those associated with a deficiency of folate. This was an even more important insight. Researchers noted that, in humans, research shows that impaired folate uptake into the brain can cause cerebral folate deficiency, a syndrome that is often associated with the development of autism.

Dangers of folate overdose

Women who have given birth to a child with neural tube defects or who have certain conditions like epilepsy and take anticonvulsants, have generally been advised to take much higher doses of folic acid. Researchers say that in animal models, there are indications that very high amounts of folic acid can be harmful to brain development of the fetus. They say that the clinical community should take this indication seriously, to support research in this area to reevaluate the amount of folic acid that is optimal for pregnant women. They further add that the problem may also lie in the way folic acid is metabolized by the body. This needs to be investigated further.

Important to get the dosage right

A panel with the National Academy of Sciences and the Institute of Medicine (now called the National Academy of Medicine) had determined the recommended daily intake of folic acid (400 mcg) and the maximum daily safe upper limit (1000 mcg) for pregnant women. The Food and Drug Administration (FDA) also recommends adding folic acid to foods. In fact, this recommendation led to the fortification of all cereals and grains with folic acid in 1998 in the US. Researchers of the above-mentioned study say that addition of folic acid to diet was a good thing. But there is a 'best amount' of folic acid, and some people may be getting more than is optimal.

Benefits of folic acid for pregnant women

Folic acid, which is the synthetic form of vitamin B9, or folate, supplements are commonly recommended for women of child-bearing age. This can substantially bring down the risk of neural tube defects, such as spina bifida, in children. Prenatal vitamins that include folic acid offer protection against the development of autism and other disorders. Many studies have shown this to be true.