February 2013

Maternal Folic Acid Supplementation May Reduce Autism Risk

A new study suggests that folic acid supplementation during pregnancy may reduce the risk for autism in children.

Folate and folic acid are forms of the water-soluble B9 vitamin. Folate occurs naturally in food, and folic acid is the synthetic form of this vitamin. Folic acid is well-tolerated in amounts found in fortified foods and supplements. Sources of folate include cereals, baked goods, leafy vegetables (spinach, broccoli, lettuce), okra, asparagus, fruits (bananas, melons, lemons), legumes, yeast, mushrooms, organ meat (beef liver, kidney), orange juice and tomato juice. Folic acid is frequently used in combination with other B vitamins in vitamin B complex formulations.

Folic acid is strongly recommended by healthcare professionals at the start of pregnancy and even before conception. Folic acid is needed for the closing of fetus' neural tube. The neural tube is the fetus's precursor to the brain and spinal cord. Folic acid thus helps prevent spina bifida, a very serious birth defect.

In a recent study, researchers analyzed data from the Childhood Autism Risk from Genetics and Environment Study, including 429 families with an autistic child, 130 families with a child of delayed development and 278 families with a child of normal development. Data on maternal folic acid intake, including dose, brand and frequency of use, was collected through telephone interviews.

The researchers found that maternal folic acid intake was significantly higher during the first month of pregnancy for families with children of normal development when compared with families with an autistic child. Furthermore, an average of at least 600 micrograms of folic acid intake daily was linked to a reduced risk for autism. The authors noted that there was a trend toward a link between low folic acid intake during the first three months of pregnancy and having a child with delayed development; however, a significant link was lacking.

The authors concluded that high folic acid supplementation during pregnancy may reduce the risk for autism in children; however, further research is warranted before a strong conclusion can be made.

In addition to folate and other vitamins, minerals, such as calcium and iron, are particularly needed by the rapidly growing fetus. Pregnant women should eat enough dairy products (for calcium) and red meat (for iron) if they are not lactose intolerant or vegetarian. Women who do not eat dairy or meat can obtain calcium and iron from fortified soy milk and juice, soybeans and certain leafy greens. Calcium is effective only if women also obtain enough vitamin D. Vitamin D can be made in the body after exposure to ultraviolet rays from the sun or from food sources. Although milk is fortified with vitamin D, dairy products made from milk, such as cheese and ice creams, are generally not fortified with vitamin D. Cold water fish such as salmon, mackerel and sardines also good sources of vitamin D.

For more information about folate and folic acid, please visit Natural Standard's Foods, Herbs & Supplements Database.

Also try Natural Standard's NEW Pregnancy & Lactation Checker, an easy-to-use tool for consumers and healthcare professionals seeking safety data on integrative therapies for pregnant and breastfeeding women.

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  1. Natural Standard: The Authority on Integrative Medicine.
  2. Schmidt RJ, Tancredi DJ, Ozonoff S, et al. Maternal periconceptional folic acid intake and risk of autism spectrum disorders and developmental delay in the CHARGE (CHildhood Autism Risks from Genetics and Environment) case-control study. Am J Clin Nutr. 2012 Jul;96(1):80-9. doi: 10.3945/ajcn.110.004416. 

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