Picture (l to r):  Nichole had a 12 pound weight loss in 4 weeks, Julie lost 4 1/2 inches all over in the first 4 days, Kathy reversed her slowing creeping weight gain and dropped a dress size, Evelyn lost 1 1/2 inches of belly fat in the first 4 days   We hear it from Prevention readers again and again: Despite all your best weight loss and exercise efforts, you just can’t lose weight around your middle, especially once you hit 40.  Shrinking an expanding waistline is not only a matter of vanity: Excess belly fat can significantly up your risk of heart disease, the number one killer of women, as well as other dangerous medical conditions. We’re all familiar with subcutaneous fat—the jiggly stuff that makes it hard to zip up your jeans. But it’s the visceral fat—the type residing deep inside your belly—that’s so deadly. This compact fat, sometimes called “hidden” belly fat, builds up between and around your internal organs. Even small amounts can increase your heart disease risk. It can also cause metabolic syndrome, a cluster of conditions that include high LDL, the “bad” cholesterol, as well as high blood pressure and high blood sugar, which can progress to type 2 diabetes. A study published in the Archives of Internal Medicine found that in a sample of more than 3,000 people, 46% of overweight women and 22% of normal-weight women had metabolic syndrome, and those who did had 50% more visceral fat. Since most of us take measures to eliminate only the fat we can see, how do you get rid of the dangerous stuff hiding inside? Better yet, is there a way to eliminate both? We dug into the science and developed the Flat Belly Diet; a weight loss plan that can change your body and protect your health: Researchers have discovered that eating fat—a very specific kind—is actually one of the best ways to fight both subcutaneous and visceral belly fat. A cutting-edge study published in Diabetes Care in July 2007 and conducted by scientists at Reina Sofía University Hospital in Córdoba, Spain, placed a group of overweight people on 4-week diets containing the same number of calories but with different ratios of carbohydrate and fat. The weight loss plan rich in monounsaturated fats prevented the accumulation of both types of belly fat—without additional exercise.  Need proof that it works? Keep reading for two amazing success stories. [pagebreak]

SUCCESS STORIESMary Anne: She’s down 36 pounds and still losing 

Diane: She did it for her health

  25 in. lost in 3 months Weight loss has also worked wonders for her love life. “My husband looks at me and says, ‘Wow!’ He can’t keep his hands off me.” The couple is renewing their vows soon. Mary Anne says, “I’m looking forward to wearing a beautiful gown I haven’t been able to fit into in a long, long time.”          6.25 in. lost in 4 weeks Joining the test panel has transformed her life. In the past, she’d come home from work and plop onto the sofa at 4 pm, done for the evening. Things are different now. “The food I’m eating and my weight loss have energized me,” she says. She’s now out in the evenings and wanting to do more and more. “It’s as if I’ve gotten back another 6 hours a day,” says Diane. “Cancer takes away some of your control over your life, but now I feel as though I have a handle on my future.”   More from Prevention: 25 Quick And Easy Flat Belly Meals    START REDUCING BELLY FAT TODAY! Get your copy of the bestselling Flat Belly Diet