According to new research, increased soluble fiber consumption may reduce the amount of deep belly fat that we accumulate. Soluble fiber sources include oatmeal, lentils, apples, nuts, celery and carrots, among others. The study found that, for every 10-gram increase in soluble fiber eaten per day, deep belly visceral fat was reduced by 3.7 percent over five years. In addition, the study reported that moderate activity resulted in a 7.4 percent decrease in the rate of visceral fat accumulation over the same time.