Researchers from Curtin University in Australia and several universities in Ethiopia have found that taking folic acid and multivitamin supplements during pregnancy may lower a child’s risk of developing autism spectrum disorder (ASD) by around 30%.
Their study reviewed many past studies and combined the results to get a clearer answer.
ASD affects up to 1% of children globally. It can make it difficult for children to interact with others, understand social cues, and communicate. Children with ASD often face additional challenges such as anxiety, attention problems, epilepsy, and trouble sleeping.
Many factors can influence the risk of a child developing ASD. Some of these are genetic, while others come from the environment. One environmental factor that can be changed is a mother’s nutrition during pregnancy. Folic acid and multivitamins are commonly recommended to pregnant women to support their health and their baby’s development.
Folic acid plays an important role in forming the baby’s brain and spine. It also supports DNA changes that help with healthy brain growth. Multivitamins usually include nutrients like vitamin B12, vitamin D, and iodine. These nutrients support the immune system, help reduce inflammation, and assist with brain and nerve development.
In the past, studies on whether these supplements actually lower the risk of autism have had mixed results. Some found a link between supplements and lower ASD risk, while others found no clear connection.
These differences may be due to how the studies were done, what kinds of supplements were used, when and how long they were taken, and how autism was diagnosed.
To sort through all this information, the researchers carried out what’s called an “umbrella review.” This type of review combines data from many earlier studies to give an overall picture. Their review included eight systematic reviews and meta-analyses, covering a total of more than 3 million people from 101 studies.
Six of the eight reviews showed that taking folic acid and/or multivitamins during pregnancy was linked to a lower risk of autism in children. Two studies found no link. When the researchers combined all the data, they found that taking either folic acid or multivitamins during pregnancy reduced the child’s risk of ASD by about 30%.
When they looked at the types of supplements separately, multivitamins were linked to a 34% lower risk and folic acid alone was linked to a 30% lower risk. These findings remained strong even after the researchers tested different ways of analyzing the data.
The results were considered “highly suggestive,” which means there’s strong evidence that these supplements may offer real protection. The researchers recommend that women take folic acid and multivitamins before becoming pregnant and during early pregnancy to help support healthy brain development and reduce the chance of autism.
In summary, this large review of past studies suggests that simple and widely available supplements—folic acid and multivitamins—can play an important role in lowering the risk of autism. This could be a valuable and low-cost step to take for future parents and public health programs.
If you care about autism, please read studies about a new cause of autism, and cats may help decrease anxiety for kids with autism.
For more information about health, please see recent studies about vitamin D that may hold the clue to more autism, and results showing strange eating habits may signal autism.
The study is published in PLOS ONE.
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