We’ve all been there—standing in the grocery aisle thinking, “this little chocolate-covered, cream-filled snack cake doesn’t have that much more fat in it than a handful of peanuts. For an extra 4 grams of fat, I can really indulge.”

Sure, the peanuts have 13 grams of fat and the snack cake only has 17 grams. But have you looked at the type of fats they contain or what effect they’ll have on your body? This is where the “good fat, bad fat” discussion becomes important.

Finding bad fats

There are two bad fats you need to watch for in foods: saturated fat and trans-fatty acids, also known as trans fats. Saturated fats can contribute to higher LDL (bad) cholesterol and have been linked to heart disease, stroke and breast cancer. You can easily identify saturated fats because they usually stay solid at room temperature. They’re usually found in animal-based foods such as butter and lard, as well as tropical oils, such as coconut or palm oil and cocoa butter.

Trans fats can raise LDL cholesterol even higher than saturated fats. Trans fats are used in many processed foods and commercial baked goods because they help preserve foods. Some trans fats occur naturally. Some are created by bubbling hydrogen into vegetable oil to create “partially hydrogenated” oil. If you see this phrase on food packaging, you’ll know it has trans fats.

Finding good fats

Even though some fats are considered good, they’re still fats—dense in calories and hard to work off your waistline. So you still have to approach them with a sense of balance. Unsaturated fats include the monounsaturated and polyunsaturated varieties. Polyunsaturated fats have been shown to reduce LDL cholesterol, but they may also reduce HDL (good) cholesterol. Monounsaturated fats can reduce LDL cholesterol without affecting HDL cholesterol.

Where can you find them?

Polyunsaturated fats can be found in corn, sunflower, soy and safflower oils. Monounsaturated fats can be found in canola, olive and peanut oils, as well as avocados, nuts and seeds.

Fatty acids are essential nutrients that help increase your metabolism, lower cholesterol and may reduce your risk of heart disease. There are two types—omega–6 and omega–3. Because omega–3 is found in specific foods, many people do not get enough of it. It can be found in cold-water fish, such as salmon and sardines, shellfish, canola oil, flaxseed, walnuts, pumpkin seeds, soybeans and green leafy vegetables. Today, some eggs contain omega-3, thanks to a specific diet fed to chickens.

Now take a minute to go back and review those snack choices again. In that ounce of peanuts, there are only 2 grams of saturated fat, compared to 11 grams of saturated fat in the snack cake. Armed with new information—hopefully you’ll choose the nuts over the snack cake!

Check out this article on Choosing Healthy Fats for more tips on good fats, bad fats and the power of Omega-3s.