Differentiation of neural tissue does not solely rely on factors produced by the cellular mechanisms of the developing embryo. There are several nutrients derived from outside the embryo that are crucial to proper neural development.

How Iron Affects Neural Development

A group of researchers found that iron is an essential element in the differentiation of glial precursor cells. It was known that children with an insufficient diet (either pre or post natal) of iron developed hypomyelination (lack of myelinated nerves). After investigation, it was found that oligodendrocytes fail to form or mature properly in an iron deficient brain because iron availability restricts the generation of oligodendrocytes from tripotential-glial restricted precursor cells. The peak of brain iron uptake in vivo conincides with the period of greatest myelination. (29)

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