Folic acid supplementation is already recommended to prevent neural tube defects, which are often severe malformations of the brain.

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Fumonisin also interferes with the cellular uptake of folic acid, a vitamin that is known to reduce the risk of neural tube defects in developing fetuses.

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Because fumonisin prevents the folic acid from being absorbed by cells, the toxin can, in effect, induce functional folic acid deficiency and thereby cause neural tube defects such as spina bifida even when the diet contains what otherwise would be sufficient amounts of folic acid.

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Researchers at Boston University found evidence that mothers who were overweight before they became pregnant are at greater risk of having a child with neural tube defects, including spina bifida -- which can paralyze legs -- and anencephaly, which results in an underdeveloped brain.

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