Foods for a Flatter Tummy Now

While it is impossible to gain a flat stomach instantly through diet or exercise, the Flat Belly Diet is based on research suggesting that certain foods may reduce stomach fat when eaten as part of a low-calorie diet. In addition, the diet avoids foods and beverages that can cause stomach bloating and water retention, making the stomach swell. Avoiding these foods can rid your body of excess bloating and water weight, likely resulting in a flatter stomach, research by the Mayo Foundation for Medical Education and Research shows. In addition, eating a healthy, low-calorie diet can help you flatten your stomach over time.

Monounsaturated Fats

• The Flat Belly Diet, created by Prevention magazine Editor Liz Vaccariello and registered dietitian Cynthia Sass, contends that monounsaturated fatty acids, or MUFAs, help eliminate belly fat. The plan claims dieters can "lose up to 15 pounds in 32 days," and suggests a four-day "jump start" followed by a low-calorie diet that includes foods containing monounsaturated fats at every meal. These heart-healthy fats can be found in olive and canola oils, peanut butter, pistachios and pumpkin seeds. Avocados, olives and dark chocolate are also sources of this type of fat.

Calories

• Eating fewer calories than you burn will result in weight loss over time. Consume a low-calorie diet rich in a wide variety of nutritious foods for healthy long-term weight loss. Eat plenty of vegetables and fruits; they are low in calories and nutrient-rich. Choose whole grain breads and cereals, and switch from white pasta to whole wheat. Enjoy plenty of lean protein, and eat red meat in moderation. Include low-fat dairy, as well as a variety of beans, nuts and seeds in your diet.

Water

• Drinking water helps reduce bloating and water retention by diluting sodium in the body. Proper hydration also keeps the digestive tract operating smoothly, preventing stomach bloating and constipation, according to Prevention.com.

Bloating

• Many vegetables, such as cauliflower, broccoli and cabbage, cause gas and bloating, according to the Mayo Clinic. The Flat Belly Diet suggests avoiding raw vegetables during the "jump start" phase because they can result in bloating. Eat cooked vegetables instead. Fruits like apples and pears may also cause bloating, as can beans and lentils.

  Salt can cause water retention, so avoid eating salty foods or adding additional salt to your diet. Fried and fattening foods not only cause gas and bloating, but lead to additional weight gain. Artificial sweeteners and foods containing them should also be avoided, because they can cause bloating and water retention. In addition, the Flat Belly Diet suggests avoiding coffee and alcohol, which are highly acidic, to reduce digestive discomfort and bloating.