Your body needs some fat from food. It’s a major source of energy. It helps you absorb some vitamins and minerals. Fat is needed to build cell membranes, the vital exterior of each cell, and the sheaths surrounding nerves. It is essential for blood clotting, muscle movement, and inflammation. For long-term health, some fats are better than others, the good, the bad and the in-between.
“Good” fats—monounsaturated and polyunsaturated fats—lower disease risk. Foods high in good fats include vegetable oils (such as olive, canola, sunflower, soy, and corn), nuts, seeds, and fish
“Bad” fat are industrial-made trans-fats which increases disease risk. Foods high in bad fats include all processed foods made with trans-fat from partially hydrogenated oil (such as pastry, doughnut, pizza, cake)
“The in-between” saturated fats fall somewhere in the middle. Common sources of saturated fat include red meat, whole milk and other whole-milk dairy foods, cheese, coconut oil, and many commercially prepared baked goods and other foods. A diet rich in saturated fats can drive up total cholesterol, which prompts blockages to form in arteries in the heart and elsewhere in the body. For that reason, most nutrition experts recommend limiting saturated fat to under 10% of calories a day.
The percentage of calories from fat that you eat, whether high or low, isn’t really linked with disease. What really matters is the type of fat you eat. Choose foods with healthy fats, limit foods high in saturated fat, and avoid foods with trans-fat. The key to a healthy diet is to choose foods that have more good fats than bad fats—vegetable oils instead of butter, salmon instead of steak—and that don’t contain any trans-fat.