Alison Sweeney made her first TV debut at the age of 4 for a Kodak advertisement. A few years later, she appeared in two episodes of Tales from the Darkside. It wasn't until she began playing the role of Sami Brady in NBC's Days of Our Lives that she became a known actress.
Sweeney earned five Soup Opera Digest Awards for her role as Sami Brady. She has appeared on a celebrity episode of NBC's Fear Factor, and also in episodes of Friends and Las Vegas.
Throughout the '90s, Sweeney struggled with her weight, eventually fitting into a size 12 dress. In 2004, she published her first book documenting her issues with her weight in a personal memoir entitled All The Days of My Life (So Far).
In 2007, Sweeney began hosting the NBC series The Biggest Loser, replacing Caroline Rhea in the fourth season.
Sweeney married in July 2000, and has two children, Benjamin Edward and Megan Hope, whom she gave birth to right after filming an episode of The Biggest Loser in January 2009.