Lipids are group of organic molecules that include fats. While eating too many lipids, or fats, poses health problems, dietary lipids still play important roles in the body. They include enhancement of nutrient absorption and immune system function, for example. The Mayo Clinic recommends limiting fat to 20 to 35 percent of your total daily calories, and choosing primarily nutritious varieties. In other words, not all lipids are created equal. For best results, incorporate lipid sources into a healthy, balanced diet. For specified guidance, consult your doctor or dietitian.
Oils enhance the texture and flavor of salad dressings, baked goods and many prepared foods. They also keep foods from sticking to pans and grills. However, the nutritional values of different oils vary. Plant-derived oils, such as olive, canola and walnut, provide mainly unsaturated lipids -- fats that promote heart health, according to the Cleveland Clinic. Flaxseed and walnut oils also supply omega-3 fatty acids -- essential lipids that play an important role in brain function. Wheat germ oil is a top source of vitamin E -- a potent antioxidant.
Hydrogenated Vegetable Oils
The Mayo Clinic calls trans-fats a "double whammy" against heart health. Hydrogenated vegetable oils are major sources of trans-fats -- lipids that can increase your LDL, or "bad," cholesterol and lower your HDL, or "good," cholesterol. The American Heart Association recommends limiting trans-fats to no more than 1 percent of your daily calories. For someone with a 2,000 calories-per-day diet, this is equal to a max of 20 calories or 2 grams. Avoid processed foods that list hydrogenated vegetable oils as an ingredient. Sources that are particularly high in trans-fat include hard margarine, shortening, fast food and commercially prepared pie crust, pizza dough, cookies, frosting and biscuits.
Meats, Seafood and Dairy Products
Meats, seafood and dairy products contain saturated fats. The AHA recommends limiting saturated fat to 7 percent or less of your total daily calories. This is equal to 140 calories or 16 grams if you eat 2,000 calories per day. To stay within these limits, choose primarily lean protein sources, such as fish, extra-lean ground beef, skinless white-meat poultry and low-fat yogurt. Plant protein sources, such as beans and lentils, are naturally free of saturated fat. Salmon, halibut and other oily fish provide valuable amounts of omega-3 fatty acids. Unlike saturated fats, omega-3s minimize inflammation.
Nuts, Seeds and Avocados
Like plant-derived oils, nuts, seeds and avocados provide heart-healthy unsaturated lipids. People who eat nuts routinely are less likely to have heart attacks or die from heart disease than people who don't usually eat them, says the Harvard School of Public Health. The healthy lipids in nuts, seeds and avocados can also help improve your LDL and HDL cholesterol levels. Swapping out saturated lipid sources, such as butter and high-fat cheese, with mixed nuts, natural trail mix and avocado slices, for example, can help keep your unhealthy fat intake in check. For omega-3s, add walnuts or ground flaxseeds to smoothies, baked goods or cereals. Avocados are fiber-rich alternatives to mayonnaise and other fatty sandwich toppings.
- Mayo Clinic: Healthy Diet: End the Guesswork with These Healthy Guidelines
- University of Maryland Medical Center: Omega-3 Fatty Acids
- Office of Dietary Supplements: Vitamin E Fact Sheet
- Mayo Clinic: Trans fat is Double Trouble for Your Heart Health
- American Heart Association: Trans Fats
- American Heart Association: Saturated Fats
- Harvard School of Public Health: Nuts for the Heart
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