Science teacher eats nothing but McDonald's food to lose weight

POSTED: 1:04 PM Jan 06 2014   UPDATED: 1:05 PM Jan 06 2014
John Cisna

An Iowa high school science teacher decided to do an unusual fast-food experiment: lose weight by eating only at McDonald's. It's kind of a reverse "Super Size Me," and he even got his students to plan his menu. ABC's Sara Haines reports on how the three-month experiment went.