On this most blessed of days, the Centers for Disease and Prevention is telling everyone to stay the hell away from a different sort of green, one that might cause you to have bloody diarrhea and vomiting for days on end: romaine lettuce. Just today, officials updated their warning over an outbreak of Escherichia coli linked to romaine that has spread to at least 16 states and sickened over 50 people since mid-March.