I had just finished reading the post on whole grains on Sybil's blog "Nutrition Nibbles" and was browsing for some studies to prove that whole foods were indeed good.That's when I found this study that was conducted about a year ago by Heather I Katcher at the Pennsylvania State University and published in the American Journal Of Clinical Nutrition.
The study was conducted on 50 obese adults with metabolic syndrome (metabolic syndrome is a collection of risk factors that increase the risk for diabetes and heart disease). They were divided into two groups and put on a reduced calorie diet for 12 weeks.One group was given only whole foods while the other group had absolutely no whole foods. At the end of the study,both groups lost weight and also showed a decrease in body fat,but the whole foods group lost more belly fat. Not just that,the whole foods group even had a decline in C-reactive protein (a marker for inflammation in the body and high levels of CRP are associated with increased risk of heart disease).
The bottom line: if you want a flat stomach ('wash board abs' as it's more popularly known as), just exercising may not be enough. Include more whole grains and REDUCE the consumption of refined foods.