Fruit and vegetables are low in calories and nutrient dense, which means they are packed with vitamins, minerals, antioxidants, and fiber. Focus on eating the recommended daily amount of at least five servings of fruit and vegetables and it will naturally fill you up and help you cut back on unhealthy foods. A serving is half a cup of raw fruit or veg or a small apple or banana, for example. Most of us need to double the amount we currently eat.
Going gluten-free may be a popular trend, but unless you're actually gluten-intolerant or have celiac disease, plenty of reasons exist to continue eating whole grains. They're a tasty way to fill up on both soluble and insoluble fiber, which help you feel full for longer and keep bowel movements regular (oats, barley, and bulgur are especially high sources). Whole grains can also help prevent weight gain: in one study, women who ate whole grains like wheat germ and dark bread had a 49% lower risk of "major" weight gain over time.