While doing a little light reading I came across this blurb in VegNews Magazine April 2013 issue:
"A team analyzed data from roughly 80,000 people over a three-year period and found that participants who at a 2.8 ounce serving of produce (the average apple weighs 5.3 ounces) SEVEN times per day were the happiest. And along with more smiles research from the European Journal of Epidemiology suggests a produce-heavy diet in children is correlated with high IQ's. Happy and Smart? We'll take it."
My thought on this is when you eat good, you feel good - not just your body functioning well but you feel good about yourself. Go eat yourself happy!