In addition to making our pants feel uncomfortably tight around the waistline, excess belly fat can be a sign we’re living an unhealthy lifestyle. The stress hormone cortisol causes fat to build up around the midsection, surrounding the organs and making it harder for the body to function properly. For this reason, controlling stress levels is the most important step we can take to flatten our stomachs. Exercise also helps to tone the abs, so we train our muscles and try to build core strength with consistent workouts. But every fitness trainer in the world will tell you that exercise is only half of the picture: the other part is diet. This means you can do all of the sit-ups you want, but if you’re eating too much or consuming the wrong foods, you’re still going to have belly fat. In addition to avoiding sugar, which is stored as fat when eaten in excess, there are foods everyone can choose to promote abdominal weight loss. Below are some favorite foods recommended by fitness and nut...