Dietary fat: Know which to choose
Fat is an important part of your diet, but some kinds are healthier than others. Find out which to choose and which to avoid.
By Mayo Clinic Staff
Dietary fat is essential to your health. It gives you energy and helps your body absorb vitamins.
But some types of fat may play a role in heart disease and stroke. In addition, fat is high in calories. Eating too many calories can lead to weight gain and possibly obesity.
Find out which type of fat to choose — and which to avoid — for good health.
The facts about fat
Most foods contain a mix of different kinds of fat. For example, canola oil contains some saturated fat but is mostly monounsaturated fat. In contrast, butter contains some unsaturated fat but is mostly saturated fat.
What's the difference between saturated and unsaturated fat?
- Saturated fat. This is solid at room temperature. It's found in butter, lard, full-fat milk and yogurt, full-fat cheese, and high-fat meat.
- Unsaturated fat. This tends to be liquid at room temperature. It's found in vegetable oils, fish and nuts.
Saturated fat
The Dietary Guidelines for Americans recommends limiting saturated fat to less than 10% of calories a day. The American Heart Association recommends staying under 7% of daily calories.
Why? Because saturated fat tends to raise low-density lipoprotein (LDL) cholesterol levels in the blood. High cholesterol levels can increase your risk of heart disease and stroke.
Saturated fat occurs naturally in red meat and dairy products. It's also found in baked goods and fried foods.
Trans fat occurs naturally in small amounts in red meat and dairy products. Trans fat can also be manufactured by adding hydrogen to vegetable oil.
This artificial form of trans fat is known as partially hydrogenated oil. It has unhealthy effects on cholesterol levels and increases the risk of heart attack and stroke. For this reason, partially hydrogenated oil can no longer be added to foods in the U.S.
Unsaturated fat
Studies show that eating foods rich in unsaturated fat instead of saturated fat improves blood cholesterol levels, which can decrease your risk of heart attack and stroke.
One type in particular — omega-3 fatty acid — appears to boost heart health by improving cholesterol levels, reducing blood clotting, reducing irregular heartbeats and slightly lowering blood pressure.
There are two main types of unsaturated fat:
- Monounsaturated fat. This is found in olive, canola, peanut, sunflower and safflower oils, and in avocados, peanut butter and most nuts. It's also are part of most animal fats such as fats from chicken, pork and beef.
- Polyunsaturated fat. This is found in sunflower, corn, soybean and cottonseed oils. It's also found in walnuts, pine nuts, flaxseed, and sesame, sunflower and pumpkin seeds. Omega-3s fall into this category and are found in fatty fish, such as salmon, herring and sardines.
How can I start eating healthier?
Focus on replacing foods high in saturated fat with foods rich in unsaturated fat.
Try these tips to reduce unhealthy fat in your diet:
- Use oil instead of butter. For example, saute with olive oil instead of butter, and use canola oil when baking.
- Eat fish rich in omega-3 fatty acids, such as salmon, instead of meat at least twice a week.
- Choose lean meat and skinless poultry. Trim visible fat from meat. Remove fat and skin from poultry.
- Limit processed foods, which often contain saturated fat. Instead reach for whole fruits and vegetables when you're hungry.
Don't go to extremes
You don't have to cut fat from your diet. But be smart about the amount and type of fat you choose. Remember fat is high in calories. Choose foods rich in healthier unsaturated fat instead of foods high in saturated fat, not in addition to them.
April 08, 2021
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