Fresh drinking water. That's right: water is a powerful appetite suppressant and if you drink an 8-ounce glass of water when you first start feeling hungry, you will find that it suppresses your appetite in nearly every case. If you just drink a full glass of water and have the discipline to wait 10 minutes, you will find that your appetite is either completely gone or dramatically reduced.
Your next choice, if water does not do the trick for you, is to drink organic vegetable broth. You can get organic vegetable broth from Trader Joe's, health food stores, or even many of the finer grocery stores that have a natural health section.
The next best strategy is to turn to green vegetables such as lettuce, cabbage, bokchoy, and other leafy vegetables. They have so few calories that they dont even really count in terms of calories. Have large servings of fresh, steamed or stir-fried green leafy vegetables with each meal especially breakfast. Of course, you will also need some protein likes pea, bean or lentils and healthy fat like oil or butter.
Eat apples or pears BETWEEN MEALS when your hungry as your only type of snack. Sure, they have some calories, but the apple will fill you up for quite a while, give you some energy and that will stop you from eating far more calorie-dense foods.
One more supplementary strategy to all of this is that you can multiply the appetite suppressing effects of all foods by taking some fiber before you begin eating. Fiber powder or capsules would include psyllium husk, oat bran fiber, apple pectin fiber, or other natural fibers. Start with as little as one capsule or a 1/2 teaspoon and build up over a mater of days. Drink plenty of water as you take these pills because without adequate water, they can gum up in your digestive tract and in extreme cases, they can block your digestive tract. So, you want to drink plenty of water with them.