For years fat was a dirty word, something experts warned would harm our hearts as well as our waistlines. Then we were told we could eat as much of it as we wanted—as long as we avoided the bread basket.
Fortunately, researchers have now singled out what kinds of fat you should eat and how much you need every day. To make it simple, we've boiled it all down to these six facts.
1. Fat won't make you fat
You may think any fat you consume will go straight from your lips to your hips, but that's not entirely accurate. Any nutrient, whether it's a fat, carbohydrate, or protein, will be converted into body fat if you eat too much of it. While fat does pack more than double the calories per gram of protein and carbs (9 versus 4), including a reasonable amount of it in your diet won't derail your weightloss efforts. In fact, upping your fat intake may actually help you slim down: Researchers at Stanford University found that people who ate a moderate-fat diet lost twice as much weight in two months as those who followed a lowfat plan.
2. Your body needs it
A steady diet of skinless chicken breasts and hold the- dressing salads isn't just bland, it's also downright dangerous. The human body cannot survive without fat. In addition to acting as an energy source it provides a protective cushion for your bones and organs and keeps your hair and skin healthy.
What's more, fat helps your body absorb certain vitamins, such as A, D, E, and K, from all the healthy fare you so dutifully pile on your plate. These nutrients do everything from fortify your bones to protect against heart disease. According to a recent study from Ohio State University, people who ate salsa made with avocado (which is rich in healthy fat) absorbed four times more of the antioxidant lycopene and nearly three times more vitamin A from tomatoes than those who noshed on nonfat salsa.
3. Not all fats are created equal Still, don't use your body's fat needs as an excuse to inhale every chocolate chip cookie or slice of bacon that crosses your path. "There are different types of fat molecules, and some are far better for you than others," says Mo. An easy way to tell the difference? "Bad" fats (saturated and trans fats) are usually found in animal-based and processed foods (think steak, cheese, butter, and doughnuts), while "good" fats (poly- and monounsaturated ones) tend to come from fish and plant sources, such as salmon, olive and soybean oils, nuts, and seeds.
So what's so harmful about saturated and trans fats? Put simply, they wreak havoc on the heart by raising the level of artery-clogging LDL cholesterol in your bloodstream. Trans fats also lower the amount of good-for-you HDL cholesterol, which helps clear those blood vessels of plaque buildup. In fact, one Harvard study found that for every 5 percent increase in total calories from saturated fat a woman consumes, her risk of heart disease jumps by 17 percent. Good fats, on the other hand, can have the opposite effect—a woman's odds drop by 42 percent for every 5 percent increase in unsaturated fat.
That's why experts advise getting nearly all your fat calories from unsaturated fats; less than 10 percent should come from saturated fat and less than 1 percent from trans fat. To curb your intake of these artery cloggers, opt for protein sources containing good fats, such as beans and fish, or ones low in saturated fat, such as pork, chicken, and lowfat dairy. You should also also choose lean red meat—round, sirloin, and top loin. Finally, read nutrition labels on processed foods and pick ones with the least amount of saturated fat and zero grams of trans fat per serving.
4. Lower doesn't always mean better It's true that a diet high in fat is usually high in calories too, which raises your risk of becoming obese and developing chronic diseases, like heart disease and diabetes, but going too low can also be bad for your health. Research in the Journal of the American Medical Association found that people who consumed a mere 20 percent of their calories from fat had the same rates of heart attack, stroke, and certain cancers as those who ate nearly twice as much.
So just how much of the nutrient is enough? Experts recommend getting roughly 25 to 35 percent of your total calories from fat. For a woman who eats 1,500 calories a day, that's about 50 grams, or the amount in 3 ounces of sirloin, half an avocado, 2 tablespoons of peanut butter, and two cookies. (To see exactly how much you need, go to myfatstranslator.com.) These recommendations aren't meant to be followed everyday though. It's more important to average out your fat intake over the course of a week, meaning you can eat a little more one day and a little less the next.
5. Fish contains the healthiest fats Although there's no such thing as a cure-all, omega-3 fatty acids come pretty close. Research reveals that this type of polyunsaturated fat (found in cold-water fish, like salmon, sardines, anchovies, and flounder, as well as flaxseed, walnuts, omega-3-fortified eggs, and red meat from grass-fed animals) can do everything from lower your blood pressure and cholesterol levels to fight memory loss and improve your skin. Some experts say they can even perk up your mood and defend against depression.
A study at Tufts University found that people who increased their intake of omega-3 fatty acids lowered their odds of having a heart attack by 40 percent. Accordingly, the Institute of Medicine advises consuming at least 160 milligrams of omega-3s a day.
But not all types of omega-3s are equally beneficial. While the three main varieties—ALA, DHA, and EPA—are all good for you, the latter two are the more potent disease fighters. Plant sources, like nuts and seeds, are where ALA can be found. EPA and DHA are found in algae, which fish and shellfish eat, making them both excellent sources. To get enough of these nutrients, dine on salmon or another type of fatty fish at least twice a week. Not a fan of fillets? Opt for a daily fish oil capsule that's free of mercury and other contaminants. And for a supplement that's just as effective at raising your body's omega-3 levels as seafood—without the fishy aftertaste—try a DHA supplement derived from algae or krill oil.
6. "Trans-fat-free" labels can be misleading After scientists proved how harmful trans fats are to the heart, most major food manufacturers scrambled to rejigger their recipes in order to label them "trans-fat-free." But though the new and improved products are free of these fats, many are still loaded with unhealthy saturated fat from palm oil, butter, or other sources.
It's also important to know that you can't always believe everything you read: Even those products that claim to be trans-fat-free can legally still contain up to half a gram per serving. While that may seem like a minimal amount, Harvard scientists found that women who consumed as few as 4 grams a day were three times as likely to develop heart disease. To spot hidden sources of trans fat, scan ingredient lists for partially hydrogenated oil or shortening.