Research shows that people who eat breakfast are more likely to have healthier weights. But not all breakfast foods are created equal, of course—at least not in terms of achieving and maintaining a slim physique. Experts say the best breakfast for a flat belly contains foods that offer a filling combo of protein and fiber.

“Protein is the best nutrient you can add when trying to lose weight and have a flat belly,” says Brenda Peralta, RD, and Feast Good contributor. “It helps increase your metabolism slightly since it burns more calories being processed than carbs and fats.”

With that in mind, Peratta advises starting your day with the following meal:

• Omelet or egg scramble with vegetables
• One slice of whole-grain toast (optional: with avocado), or a serving of fresh fruit

“Eggs are ideal breakfast food since they are packed with essential nutrients,” says Clara Lawson, RDN. “They also have essential amino acids that help you to build and maintain strong abdominal muscles, which keep your belly straight and firm.”

Lindsey DeSoto, RDN, eats two boiled eggs almost every morning and says she’s seen a “significant improvement” in her waistline.

“Eggs are a rich source of protein that can help maintain muscle mass and reduce cravings throughout the day,” she explains. “They’re low in calories and can help you feel fuller longer. In fact, studies suggest that eating eggs for breakfast can lead to reduced calorie intake throughout the day compared to cereal.”

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Adding veggies and whole-grain bread to the mix boosts the fiber content of your breakfast. Peralta notes that fiber is not only important for having regular bowel movements, which prevents bloating—but it also adds to the satiety factor. The more fiber in your breakfast, the longer you’ll keep those hunger pangs at bay, meaning you’re less likely to need to load up on snacks between meals.

“Starting your day with high-fiber foods is a good idea because they’re digested more slowly, providing long-lasting energy,” adds Mackenzie Burgess, RDN and recipe developer at Cheerful Choices.

While you can include any vegetables you like, Peralta specifically recommends seeking out low FODMAP veggies like zucchini, tomatoes, bell peppers, and spinach.

“FODMPAPs are a group of carbs that go straight to your gut, and they get fermented by the bacteria there,” she explains. “This, in the end, causes bloating.”

Want to amp up the slenderizing power of your breakfast even further? DeSoto suggests spreading a little avocado on your whole-grain toast. This fruit is rich in monounsaturated fats, which studies have shown can reduce belly fat.

“By setting yourself up for success with a nutrient-dense meal at the beginning of the day, you’re likely to make more mindful choices throughout the day instead of reaching for the first food options in sight,” adds DeSoto.

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