1. Apples :

Apples are a good source of dietary fiber. Dietary fiber not only contributes to a healthy digestive system and reduced cholesterol, but it also benefits smart eaters by yielding no calories while keeping them satisfied.

And there's something else about the fruit that might help you feel full. A study in the journal "Appetite" found that when women added either three apples or three pears to their daily meals, they lost more weight than people who added three oat cookies to their diets -- even though the fruit and the cookies contained the exact same amount of dietary fiber.

2. Almonds :

If you're looking for a tasty midday snack, a handful of almonds are a well-regarded option. A study in 2009 in "The American Journal of Clinical Nutrition" found that women who ate nuts at least two times a week were more successful at keeping weight off than those who didn't eat this food.

3. Salmon :

If you're uncertain about fish, there's no need to fear. Seafood can be part of a healthy diet. And there's some evidence that the fat in foods such as salmon can boost satiety levels, says Aragon. For example, a study published in the "International Journal of Obesity" found that when dieters ate salmon a few times a week, they lost about two more pounds than those who didn't include seafood in their meals.

And in spite of the mention of salmon's fat content, the food is relatively low in calories. One 3-oz. serving has just 175 calories. Salmon is a good source of protein as well.

4. Eggs :

There's no doubt that protein, like fiber, has impressive satiating powers. And while eggs seem to have a bad reputation in some circles, there can be no contesting their ability to help keep your weight in check.

Research has shown that eating eggs at breakfast can help you fight weight gain all day long. A study reported in 2008 in the "International Journal of Obesity" found that when dieters ate two eggs for breakfast for five days out of the week, they lost 65 percent more weight than dieters who consumed a bagel in the morning. Although protein is likely to fill you up whenever you eat it, some scientists suspect that having more in the morning can keep you feeling fuller all day long.

5. Tomatoes :

It's true that most veggies make for great diet fare. Non-starchy vegetables in particular, such as carrots, celery and spinach, are filled with fiber. Like other foods high in fiber, they can help keep you feeling satiated.

Plus, they're pretty self-regulating, says Aragon. You can't really overeat with nonstarchy vegetables. After all, how many baby carrots can a person eat without needing to dunk them in some ranch dressing?

So while there are many veggies that can help you stay slim, tomatoes might be a particularly good option because they're so tasty. And, besides, with that whole a-tomato -is-a-vegetable-no-it's-a-fruit argument, you might have forgotten all about eating them. One cup of cooked, red tomatoes contains just 43 calories, but tastes just as delicious as any number of high-calorie foods.