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Getting over the fat phobia

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Ditch trans fats and limit saturated fats, but keep unsaturated fats in your diet.

Fats have gotten a bad rap for the last two decades, thanks to a no-fat diet trend. “People still believe that eating fat makes you fat. But it’s not true. What puts on the pounds is the combination of excess calories and too little physical activity,” says registered dietitian Kathy McManus, director of the Department of Nutrition at Harvard-affiliated Brigham and Women’s Hospital. Furthermore, some fats are good for you, while others are bad. Understanding the difference will keep you healthier.

Bad fats

There are two types of unhealthy fat: trans fat and saturated fat. Trans fats extend a food’s shelf life. They’re manufactured by a process that uses hydrogen gas to turn vegetable oils into solids. Consuming lots of trans fats increases “bad” LDL cholesterol, decreases “good” HDL cholesterol, raises the risk of blood clots, and boosts inflammation—all of which increase the risk of heart disease, stroke, and diabetes. “Trans fats should be eliminated from your diet,” says McManus. To that end, the FDA this year essentially banned trans fats in processed food.

Saturated fats occur naturally in food. They’re found mostly in animal sources, such as whole milk, butter, cheese, ice cream, and red meat, and some vegetable sources, such as coconut and coconut products. These fats can also raise LDL cholesterol and increase inflammation in your body. It’s fine to eat some saturated fats, “but keep saturated fats to 7% to 10% of your daily calories,” says McManus.

Good fats

Healthy unsaturated fats fall into two categories: polyunsaturated and monounsaturated. Mono-unsaturated fat is found in most nuts, avocados, and many oils, such as olive, peanut, and canola. Polyunsaturated fats come in two forms: omega-3 fatty acids, found in salmon, mackerel, sardines, and flaxseeds; and omega-6 fatty acids, found in corn oil, soybean oil, walnuts, and safflower oil.

“Both polyunsaturated and monounsaturated fats have been found to lower LDL cholesterol and total cholesterol when substituted for saturated fats. Omega-3s can also reduce the development of irregular heartbeats, a main cause of sudden cardiac death, and they can reduce the tendency for clots to form in the arteries and block blood flow,” says McManus.

Not only are these fats good for you, they’re also necessary to help you absorb some vitamins and minerals, build cell membranes, get your blood to clot, and move your muscles. Fat is also a major source of energy.

What you should do

Remember that each gram of fat has nine calories, which is more than in a gram of carbohydrates or proteins. So you shouldn’t eat too many of them. “If you add too many calories to your daily intake, over time that will increase your weight if you’re not compensating,” says McManus. She recommends that 30% to 35% of your daily calories come from fat—7% to 10% of them from saturated fats and the rest from unsaturated fats. To compensate for the calories you get from good fats, reduce the calories you get from less healthy foods such as refined carbohydrates and other processed foods.

Not sure where to start? Sprinkle nuts on salads or in hot cereal, plain yogurt, and whole grains; use healthy oils to roast vegetables; spread almond or peanut butter on toast, fruit, or vegetables as a snack; and add avocado slices to a salad or make an avocado spread for a sandwich. “And try putting fish on a salad, from canned sardines to salmon,” McManus says.

Fitting more healthy fats into your diet

Here’s what it looks like when 30% to 35% of your daily calories come from healthy fats (in red). This menu is based on a 1,500-calorie meal plan.

1 cup cantaloupe
1 cup oatmeal
½ cup skim milk
1 tablespoon walnuts

1 cup minestrone soup
2 ounces sardines
4 tomato slices
2 slices whole-wheat bread
2 romaine lettuce leaves
1 teaspoon mustard

1 ounce peanuts

4 ounces broiled chicken
1 sweet potato
5 mushrooms
½ cup asparagus
2 cups baby spinach
1 tablespoon olive oil
1 tablespoon vinegar
½ cup strawberries

4 whole-grain crackers
2 teaspoons peanut butter
1 cup skim milk

*Saturated fat should account for no more than 10% of daily calories.
Source: Brigham and Women’s Hospital.

Posted by: Dr.Health

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