Good Fats Versus Bad Fats
The South Beach Diet does not ask you to count grams of fat. The focus is on eating the right fats in moderate amounts. As healthy as they are for you, good fats are also calorie dense and should be consumed judiciously during all Phases of the South Beach Diet. Our suggestion is to limit added oils to approximately 2 tablespoons per day and limit nuts to about 1/4 cup a day. But what are the good fats and the bad fats, and how can you identify them on a nutrition label?
Good fats are the unsaturated fatty acids our bodies need to survive. Unsaturated fats are either monounsaturated or polyunsaturated. Monounsaturated fats can be found mainly in olive, peanut, avocado, and canola oils. There are two types of polyunsaturated fats  omega-3s and omega-6s. Omega-3s are found in some nuts; flaxseed and other seeds; and all seafood, especially fatty cold-water fish such as salmon, tuna, sardines, and herring. Omega-6 fats are found in corn, safflower, and sesame oils and also in grains. Both omega-3s and omega-6s are called essential fatty acids because they are required by the body and must be obtained through food sources or supplementation.
Omega-6 fats are dependent on interactions with omega-3s for optimal health benefits, but omega-6s are considered good fats only when consumed in moderation and in proper proportion with omega-3s. When too many omega-6 fats are consumed, they tend to be pro-inflammatory, whereas omega-3 fats are anti-inflammatory. The latest research suggests that a normal ratio of omega-6s to omega-3s in a healthy diet should be 4:1.
Bad fats include saturated fats (often referred to as animal fats) and trans fats. Saturated fats are found primarily in fatty cuts of beef, lamb, and pork; in poultry with the skin; and in full-fat dairy products. There are also plant sources of saturated fats, including coconut, palm, and palm kernel oils, but it's still unclear how bad they are for you. The really bad fats are trans fats, which are created when hydrogen is added to vegetable oil  a process called hydrogenation  to increase the shelf life and stability of foods. Trans fats can be found in stick margarines (but not in most soft tub or liquid margarines), vegetable shortenings, foods fried in hydrogenated oils, and many packaged snack foods containing hydrogenated or partially hydrogenated oils. Trans fats have been shown to raise bad cholesterol levels and lower good cholesterol levels.
Read nutrition labels carefully to fully understand the nature of the fat content. Fat is currently broken down into two categories under the nutrition-facts panel. The first shows the total fat grams, and the second shows the grams of saturated fat. Remember that good fats include unsaturated fats, which may be listed as extra-virgin olive oil, canola oil, corn oil, or a variety of other vegetable oils.
Trans fats are listed in the ingredients as "hydrogenated" or "partially hydrogenated" oils. If you identify trans fats in a product, try to avoid purchasing it.
