A Mexican who used to weigh 1,311 pounds will undergo bypass surgery to save his life. Juan Pedro Franco is believed to be the heaviest man in the world.The 31-year-old has already lost 385 pounds to prepare for the surgery. Battling obesity all his life, Franco hopes the surgery will allow him to live normally. He has been bed-ridden for the last seven years.Mexico is the global leader in obesity, with 35% of adolescents overweight or obese.