Over the last six months, Mary Anne has lost 50 pounds. "I feel great!" she says. "I struggled for years with weight, and I finally found something that worked and I'm just very happy about it!" Mary Anne attributes her success to the @[**Flat Belly Diet**](http://www.flatbellydietbook.com), a new plan created by Liz Vaccariello and nutritionist Cynthia Sass of @[*Prevention*](http://www.prevention.com/) magazine. "It's a way to eat and think that targets belly fat specifically," Liz says. Cynthia explains that the program consists of four 400-calorie meals a day, and each meal contains a MUFA. "A MUFA is a mono unsaturated fatty acid," she says, "and this is the healthful oil that's found in a number of plants. The five types are olives, oils, nuts & seeds, avocados and dark chocolate. When you include that within the 400-calorie meal it's going to help regulate your blood sugar and your insulin levels, so you're going to delay the return of your hunger." Liz adds, "Exercise is not a mandatory part of the Flat Belly Diet. You will see results if you just follow the food portion of the diet." Cynthia warns that beyond just wanting a leaner look, there's a more serious issue surrounding belly fat, "especially the really deep internal belly fat around your organs. It creates inflammation which we know is a creator of disease in the body -- of aging, heart disease, type two diabetes, certain cancers, high blood pressure -- they are actually caused by this internal belly fat. Even small amounts of excess belly fat can be dangerous. It's really the most deadly type of fat on your body." While Mary Anne is satisfied with her results, two of Rachael's viewers decide to put the program to the test themselves. Heather is frustrated that seven months after giving birth, she's still left with "that little piece of fat that just won't go away." She finds that the four-day jump start portion of the program, which targets belly bloat and water retention, yields positive results. "The four-day diet definitely worked," Heather says. "I found it really easy -- yet difficult -- at times. Easy because the foods were great and the selection was great -- for dinner I made grilled tilapia, greens beans, brown rice. The difficult part was the planning breakfast, lunch, and dinner. But in the end, I lost 2 pounds." Maureen is a busy stay-at-home mom, which has lead to some unhealthy eating habits and photos of a larger woman she doesn't recognize. "I often see myself in pictures and I think, who is that?" she laments. After the four-day jump start, Maureen proudly proclaims, "I lost seven pounds! It was really easy for me -- I took the Belly Bloat quiz and realized I was drinking soda, chewing gum, eating a lot of carbs, and cutting that out, I lost seven pounds. I can't wait to start the rest of the diet!" "Whoa, I can't cut out carbs!" Rach protests. "I'm Sicilian, I'd get kicked out of my family!" Cynthia calms her fears: "It's not about cutting them out," she says, "It's just cutting back." Liz sums up the diet's ultimate philosophy: "The diet is all about good food that tastes good, keeping full, and being motivated," she says.