Wild retirement community; sex and job performance; new cancer test; a brutal attack on a teen is broadcast on social media; Gwyneth Paltrow's diet plan.

The show's most memorable moments from the past 10 years; a woman regains her hearing; a 685-pound teen with the voice of an angel; the booty that broke the Internet; the show's most-watched clip of all time; how to stop bleeding gums in 30 seconds.