Drew Ramsey is an assistant clinical professor of psychiatry at Columbia University and is co-author of "The Happiness Diet." He wrote this in the New York Times:
"Meat, fish and eggs are our only concentrated dietary sources of vitamin D, vitamin B12, omega-3 fats (which play a huge role in brain health), heme-iron (which increases the absorption of iron from vegetables) and conjugated linoleic acid, which appears to fight cancer and heart disease."
"My work clearly shows that kids who eat beef early in life have a lower incidence of autism than those who do not. Human breast milk and even infant formula are excellent sources of carnitine but when we transition infants to solid food, we often feed primarily pureed vegetables and cereal, leaving a real void for carnitine production in the body."