"Perhaps we should feed fewer animals to feed more humans. Meat, especially beef, is stunningly inefficient to produce. (Growing 1,000 calories of beef takes more than 1,000 gallons of water, and wasting one kilogram of boneless beef is equivalent to wasting 24 kilograms of wheat.) Put another way, if we took all the crops we use for animal feed and biofuel and used them to feed humans, we could feed an extra four billion people"
http://huffpost.com/us/entry/720859