Shania Twain credits liquid diet for toned abs.

Shania Twain, the 57-year-old country music star, attributes her fit figure to a mainly liquid diet that includes protein shakes filled with greens. She normally sticks to one meal a day and sometimes adds a snack of peanut butter or dark chocolate. Despite her diet, Twain doesn't participate in any specific workouts. She plans on "aging naturally" and being comfortable in her own skin. Twain is set to begin her "Now" tour on Friday in Spokane, Washington.