Flaxseed is rich in two natural appetite suppressants: omega-3 fats and fiber. One tablespoon of whole flaxseed has 3 grams of fiber and about 4 grams of healthful fat; one tablespoon of ground flaxseed has 2 grams of fiber and about 4 grams of beneficial fat. Fiber from flaxseed can keep us satisfied and full without contributing any calories.