Taking Too Much Folic Acid During Pregnancy Linked to Increase Risk of Autism

Doctors recommend pregnant women to take 400 to 800 micrograms of folic acid to prevent the development of severe neurological problems on their kids, but a new research shows that too much intake of the same nutrient can increase the risk of their child developing autism spectrum disorder.

According to the study to be presented at the 2016 International Meeting for Autism Research on May 13, mothers who have more than four times the considered adequate amount of folic acid after giving birth have two times higher risk that their child will develop autism.

"We have long known that a folate deficiency in pregnant mothers is detrimental to her child's development. But what this tells us is that excessive amounts may also cause harm. We must aim for optimal levels of this important nutrient," said senior authors M. Daniele Fallin, PhD, director of the Bloomberg School's Wendy Klag Center for Autism and Developmental Disabilities, in a statement.

For the study, researchers analyzed data from 1,391 mother-child pairs in the Boston Birth Cohort, a predominantly low-income minority population. The researchers recruited the mothers at the time of their child's birth between 1998 and 2013 and followed them for several years. About 100 of the children were diagnosed with autism.

The researchers measured the amount of folic acid in the blood of the mothers within the first one to three days of the delivery.

They discovered that one out of 10 mothers had a folic acid levels higher that the considered adequate amount in their blood. They also found out that 16 out of the more than 100 mothers with a child diagnosed with autism have very high levels of folic acids, while 15 of them have extremely high levels.

Some experts are skeptics about the study saying that the findings are preliminary numbers, and based on a small number of families seen at only one hospital.

In an interview with CBS News, Dr. Dr. Jon LaPook warned expecting mothers not to misinterpret the study. He also mentioned that folic acids should still be taken by pregnant women.

"This does not mean that taking too much B12 or folate causes autism, it's an association," Dr. LaPook commented on the study.