Jillian Michaels, the tough-as-nails trainer from The Biggest Loser, tells Rachael that her work with the show's contestants goes beyond just getting them to lose weight. "You're rebuilding lives as opposed to building a body," she explains. "One is fitness and one is transforming lives." One person who is looking to transform her own life with Jillian's help is Marilyn Kentz, former star of the '90s comedy series The Mommies. Marilyn admits to gaining 40 pounds since her television days, and says she's tried every diet program to no avail. "I just can't seem to stay with it," she cries. "Now Jillian's coming over today and I'm a little scared!"

Jillian wastes no time getting to the root of Marilyn's issues. "It doesn't take a genius to realize that you need to eat a little bit less and move a little bit more," she tells her. In order to get Marilyn moving, Jillian gives her a NordicTrack Incline Trainer with preprogrammed workouts and exercise DVDs to incorporate resistance training. Next, Jillian takes a garbage bag to Marilyn's pantry, tossing out processed snack foods, sugary items, fatty cream sauces and other no-nos. With her new tools in place, Marilyn is ready to begin reaching her way to the goal Jillian set for her -- to lose 20 pounds in 30 days. "I'm a little nervous," she says, "but I'm going to try my best!"

As Jillian explains in her book Master Your Metabolism, there's more that goes into eating less and moving more. "Of course there's the one universal truth: Fewer calories in and more calories out," she tells Rachael. "But the quality of the food you eat will dramatically affect your natural metabolism which means you're already more calories out before the exercise." Jillian advises to go organic whenever possible, but this includes more than buying natural fruits and vegetables. "It's also getting rid of chemicals in your food, your water -- get a water filter, change your air filters, use natural beauty products, cook on iron instead of Teflon, keep your food in glass instead of plastic ... you're never going to be perfect, but wherever you can mitgate damage wherever possible it makes a huge difference in your overall health and wellness.

After 30 days, Rachael checks in with Marilyn to see how she did. "It wasn't as bad as I thought," she admits, sharing that she dropped four dress sizes. But did she reach her goal of losing 20 pounds? 18 pounds "Ooh, those last two pounds are killer" she jokes, still excited for her 18-pound weight loss.