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Fats, we often hear, are the enemies lurking in our food. If we can rid our diets of them, we'll give ourselves a better chance at avoiding high cholesterol levels, heart disease, and stroke. That's true -- for some fats. Yet others are essential for energy and the absorption of nutrients. Knowing the difference can be one of the most important steps you take toward good health.

Then put that knowledge into action with our low-fat recipes and cookbooks.

What are Fats?
First the science: Fats are chemical compounds (of glycerol and fatty acids) that are derived from plants and animals, are mostly insoluble in water, and may be solid (butter, for example) or liquid (oils) at room temperature. How those fatty acids (comprised of carbon and hydrogen atoms) are structured, determines whether the fat is saturated, unsaturated, polyunsaturated (omega-3 and omega-6 fatty acids), or a trans fatty acid. The more hydrogen atoms, the more saturated the fat. And the more saturated the fat, the greater the LDL ("bad cholesterol") in the bloodstream. For more details on each type of fat, see "Good Fats, Bad Fats: What's the Difference?" at AOL Health.

Daily Dose
The American Dietetic Association recommends that no more than 30% of our diet be comprised of fats, and, of that, only 10% should be saturated fats.

The Good
Aim at serving foods containing unsaturated fats -- either polyunsaturated or monounsaturated -- which studies have shown help to prevent heart disease, stroke, even rheumatoid arthritis.

1. Vegetable oils, such as safflower, canola, olive, and soybean
2. Fish -- salmon and sardines are especially rich in Omega-3
3. Nuts, such as almonds and walnuts

Try it: Pan-Grilled Salmon Fillets with Tomato and Tarragon
Try it: Stir-Fried Chicken with Wilted Spinach and Tamari Walnuts

The Bad (In Large Doses)
Saturated fats are in many of the foods we crave. You don't have to completely give up your steak or your dulce de lece ice cream, simply treat them as, well, a treat.

1. Fatty meat -- beef is the leader in this category. Opt for leaner cuts of beef, pork, and chicken; serve fish, or choose a vegetable-based main course.
2. Whole milk and creamy -- try reduced and nonfat milk
3. Cheese -- part-skim mozzarella and ricotta cheeses are easy substitutes for their full-fat cousins. If you don't care for the taste of many low-fat hard cheeses, count your brie or cheddar as a special treat.

Try it: Red Curry with Vegetables
Try it: Strawberry Sunrise Shake
Try it: Florentine Omelet

The Just Plain Ugly
Trans fatty acids (also known as partially hydrogenated vegetable oils -- it's the hydrogen that amps up the saturation) are found in many snack foods and fast foods, such as potato chips and french fries. Lacking in nutritional value, they're an invitation for high cholesterol. In a twist on a popular ad, take our advice: Just don't do it (or do it as little as possible). That's more difficult than it sounds, since trans fatty acids appear in everything from pancake mixes to frozen foods. Read the labels.

What About Cooking Oils and Sprays?
Remember that oils -- even cooking sprays -- may have desirable essential fatty acids, but they're still all fat (and pack 120 calories per tablespoon), so should be used sparingly. Safflower oil has the highest percentage of polyunsaturated fatty acids, and olive oil is tops in monosaturated fats. Baddies in this group are tropical palm kernel oil (which is being substituted for trans fatty acids in some products) and coconut oil -- which are loaded with saturated fats.

Try it: Basic Basil Pesto

Related Articles

• Browse all healthy recipes.
• Check out this healthy family-friendly menu.
• Learn the truth about whole grains.
• Watch our Healthy Chef make the foods you love better for you.
• Get tips for lowering your cholesterol from AOL Health.