To decrease your total fat and calories

Reduce fat in baked products. Reduce the amount of fat in baked products by 1/4 to 1/3. For example, if a cookie, quick bread or muffin recipe calls for 1 cup oil, use 2/3 cup instead. (Do not use this method for yeast breads and pie crusts.)
Use vegetable oil instead of solid fats. Instead of using solid fats such as shortening, lard and butter, use vegetable oil in your recipes. Types of vegetable oils include corn oil, canola oil and peanut oil. To substitute liquid oil for solid fats, use about 25% less than the recipe calls for. For example, if a recipe calls for 4 tablespoons of shortening or butter, use 3 tablespoons oil instead.
Substitute applesauce for vegetable oil in baked products. Use the same amount of applesauce as you would oil.
Use egg substitute instead of eggs. This is even better than plain egg whites.
Use plain lowfat or nonfat yogurt instead of sour cream. In baking, use plain lowfat or nonfat yogurt in the same proportion as sour cream and save on saturated fat calories. You can also substitute buttermilk or blended lowfat cottage cheese. This method produces a savings of 44 grams of fat.

1 cup sour cream = 495 calories = 48 grams total fat = 30 grams saturated fat

1 cup lowfat yogurt = 145 calories = 4 grams total fat = 2.3 grams saturated fat

Use skim or 1% milk instead of whole milk or half and half. Another way to decrease the amount of fat and calories in your recipes is to use skim milk or 1% milk instead of whole milk or half and half. For extra richness, try evaporated skim milk. This method produces a savings of 25 grams of fat.

1 cup 1% milk = 100 calories = 3 grams total fat = 1.6 grams saturated fat

1 cup half and half = 315 calories = 28 grams total fat = 17.3 grams saturated fat

Use cornstarch and skim milk to make sauces creamy. To your non-fat/low-fat sauce add 1 tbsp. of cornstarch to 1/2 cup skim milk. Add a little at a time stirring constantly until you get the consistency you want.
When preparing any soups, stews, pot roasts or stocks, skim the fat off. The easiest method to decrease the fat content is to add the meat to the pot, cover with cold water and bring to a boil. As it reaches the boiling point, the fat will rise to the surface and becomes foamy and semi solid. It can be easily skimmed off with a spoon at this point. As it boils, continue to skim until no more fat foams up. Other ways include skimming off at the end or putting it in the fridge and allowing the fat to solidify on top so it can be removed later.

To decrease sodium
Use low sodium or unsalted ingredients. To decrease the amount of sodium in your foods, use low sodium or unsalted ingredients in your recipes. Sodium intake for adults should be 1,100 - 3,300 mg per day. This equals about 1/2 to 1 1/2 teaspoons salt. (Do not omit salt in yeast breads because it controls the rising action of yeast.)

1 teaspoon salt = 2,130 milligrams sodium

1 teaspoon soda = 820 milligrams sodium

1 teaspoon baking powder = 330 milligrams sodium

To decrease sugar
Reduce sugar in baked goods and desserts. Reduce sugar by 1/4 to 1/3 in baked goods and desserts. Cookies, quick breads and cakes can be successfully baked this way. Substitute flour for the omitted sugar. (Do not decrease sugar in yeast breads because sugar feeds the yeast.)

To increase the flavor
Use spices to increase the flavor in addition to reducing the amount of sugar in your recipes. Adding cardamon, cinnamon, nutmeg or vanilla to your recipes will enhance the impression of sweetness.

Reference: Ohio State University - Human Nutrition and Food Management