Babies' Mental Delay Tied to Moms' Vegan Diet - Thu Jan 30, 4:40 PM ET By Alison McCook

NEW YORK (Reuters Health) - The breast-fed infants of two mothers who did not eat any animal products, including milk and eggs, developed brain abnormalities as a result of a vitamin-B12 deficiency, the US Centers for Disease Control and Prevention (CDC) reported Thursday.

The primary sources of vitamin B12, which is essential for brain development, are animal products like meat, dairy products and eggs. Since the mothers ate little or no animal products, too little vitamin B12 was transmitted to their children through breast milk, according to the CDC's Dr. Maria Elena Jefferds.

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