What You Need to Know About Fats
In the past, eating low-fat seemed the way to go. Now experts say it’s fine to eat a bit more fat, but be sure to eat more good fats and less bad fats. We explain which fats fall into each category and why.
The Skinny on Fats
After some years of recommending that you rein in your fat-gram count to no more than about 30 percent of your calories, the current Dietary Guidelines for Americans, along with the Academy of Nutrition and Dietetics and the Institute of Medicine, recommend you get 20–35 percent of your total daily calories from fat. If you were to eat about 1,500 calories a day, that would equate to 33–58 grams of total fats per day. Each serving of fat or oil, such as a teaspoon of butter, mayonnaise, or salad dressing, is roughly 5 grams of fat. Keep in mind that some of the fat you eat comes from what you put in and on foods, while other fat comes from what’s already in foods, such as meats, cheeses, and dairy foods.
While you focus on not eating too much fat, it’s become clear through research that it’s also important for your heart and health to eat more of the healthier unsaturated fats and less of the bad trans fats and many saturated fats. Why? Research shows not all fats are created equal in terms of their health effects. For heart health, you should get the majority of your fat from monounsaturated fat and polyunsaturated fat (especially the omega-3 kind), consume less saturated fat, and strictly limit trans fat because it tends to raise blood cholesterol levels. In fact, manufactured trans fat is the worst fat for your heart but is still in the food supply, albeit less than in the past.
Here’s a tour of fats and oils and the foods they’re in so you’ll know what to buy at the store and cook in your kitchen.
GOOD FATS: Monounsaturated Fat – Extra Virgin Olive Oil
Olive oil is one of the richest sources of monounsaturated fat, which has long been known to help improve cholesterol levels and prevent cardiovascular disease. But that’s not all. Olive oil is also rich in antioxidants and other phytonutrients that may help fight inflammation, high blood pressure, and cancer.
At the store: Look for extra virgin olive oil (EVOO), which, unlike other olive oils, has not undergone refinement that strips the oil of some flavor, phytonutrients, and other beneficial compounds. Compare “best by” dates on oils to find a more distant date, which suggests it’s fresher and more likely to contain higher levels of antioxidants.
In the kitchen: EVOO can be used in low- to moderate-heat cooking; it’s generally stable up to 410 degrees Fahrenheit. It’s also perfect for dipping, salad dressing, and sauces.
GOOD FATS: Monounsaturated Fat – Avocado
Similar to olive oil, more than 70 percent of the fats in avocado oil are monounsaturated, plus it is naturally packed with beneficial antioxidants including lutein, important for eye health. In a recent study of 80 men and women with type 2 diabetes, an avocado-rich diet significantly lowered total blood cholesterol, LDL (bad) cholesterol, and triglycerides over an eight-week period compared with an avocado-free diet.
At the store: You’ll get the best flavor, aroma, and nutrition in unrefined, cold-pressed extra virgin avocado oil, which is mechanically rather than chemically extracted. When shopping for a fresh avocado, give it a gentle squeeze. If it’s firm but yields to gentle pressure, it’s ready to eat.
In the kitchen: Extra virgin avocado oil can take the heat a little better than EVOO, tolerating temperatures up to 475 degrees Fahrenheit, although this may vary a bit with the variety of avocado used. Avocado oil’s buttery, nutty flavor is also perfect when drizzled on steamed vegetables or grilled asparagus. Fresh avocado slices are great on sandwiches in place of mayonnaise.
GOOD FATS: Monounsaturated Fat – Tree Nuts
Most tree nuts—including macadamia nuts, hazelnuts, pecans, almonds, and pistachios—contain more heart-healthy monounsaturated fat than any other type of fat. Plus, studies suggest regularly eating nuts may help reduce risk of major diseases, including heart disease and type 2 diabetes, as well as boost longevity.
At the store: Expand your nut repertoire and try a variety of whole, raw, or dry-roasted nuts, natural tree-nut butters, and nut oils. Some nut oils and nut butters, such as almond, are easier to find and less expensive than others, such as macadamia and pecan.
In the kitchen: If you’ve ever burned nuts when roasting them in the oven, you know their delicate oils are less heat-stable. Unrefined nut oils are best used in salad dressings and dips (such as for a crusty whole grain bread), drizzled over roasted vegetables, or tossed with whole grain pasta and herbs.
GOOD FATS: Omega-3 Polyunsaturated Fat – Oily Fish
Fish oils are rich in omega-3 fats known as EPA and DHA, which have anti-inflammatory and heart-health benefits—but that’s not all. A recent study of overweight adults with type 2 diabetes found that a daily supplement of 2 grams of EPA omega-3 fish oil for 3 months significantly improved fasting blood glucose, average blood glucose (A1C), and insulin sensitivity compared with a placebo supplement of corn oil. It’s not clear, however, whether supplements can provide all of the benefits of regularly eating fish.
At the store: Buy oily seafood that is rich in omega-3s but low in mercury, such as salmon, canned sardines, Pacific oysters, herring, and anchovies. In general, aim for at least two 4-ounce servings of oily fish per week (which equates to about 500 milligrams of EPA and DHA daily). If you’re considering buying a fish-oil supplement, talk with your doctor first.
GOOD FATS: Polyunsaturated Fat – Walnuts
Walnuts are rich in antioxidants and, unlike other nuts, contain more polyunsaturated fat than monounsaturated fat, including plant-based omega-3 fat known as ALA. The body can convert small amounts of ALA to the heart-healthy, EPA omega-3 fat. Studies suggest walnuts, as part of a heart-healthy diet, may help lower cholesterol, decrease blood pressure, and reduce inflammation, among other benefits.
At the store: Up your walnut quota within your daily calorie limit by shopping for both walnuts and walnut oil. To help protect the nut’s delicate oils from rancidity, refrigerate walnut oil after opening, and refrigerate or freeze walnuts in an airtight container after purchasing.
In the kitchen: Chopped walnuts are a super way to pump up the flavor and texture of Greek yogurt, oatmeal, pancakes, salads, pizza, and green beans. Brush a bit of walnut oil (which is not heat-stable) on fish immediately after baking, or drizzle it on a baked sweet potato.
GOOD FATS: Omega-3 Polyunsaturated Fats – Flaxseeds
Flaxseeds are another good plant source of ALA omega-3 fats, plus they pack antioxidants and provide a bit of cholesterol-lowering soluble fiber. A recent study of people with hypertension suggests that consuming around 1 ounce (1/3 cup) of ground flaxseeds daily may help significantly lower blood pressure. Rather than worrying about a specific amount of flaxseeds to get daily, just make a note to slowly (to give your gut time to adjust to the increased fiber) start adding a bit to various dishes, and soon it will be making a significant nutritional contribution in your eating plan.
At the store: You can either buy whole flaxseeds, which have a longer shelf life but should be ground before using to get the benefits, or flaxseed meal (ground flaxseeds), as well as flax oil. Keep flaxseed meal and oil refrigerated to protect them from rancidity.
In the kitchen: Sneak a tablespoon or two of ground flaxseeds into oatmeal, whole grain baked goods, pancakes, casseroles, and smoothies, or sprinkle them on salads. To replace each egg in baked goods, combine 1 tablespoon ground flaxseeds with 3 tablespoons water, and let it sit for 5 minutes before adding to your recipe. Flaxseed oil can be drizzled on foods after cooking or used in salad dressing.
NOT-SO-UNHEALTHY SATURATED FATS: Stearic Acid in Dark Chocolate and Beef
We often hear that saturated fats are unhealthy for your heart and can contribute to insulin resistance. However, there are different types of saturated fats in foods that research has begun to show have different health effects. Stearic acid is one type of saturated fat that doesn’t seem to raise cholesterol. It’s plentiful in dark chocolate. Beef contains a mix of both stearic acid and the LDL (bad) cholesterol-raising palmitic acid, but even this fat also raises HDL (good) cholesterol. What to do? Opt for lean beef, which has less fat overall, or try 100 percent grass-fed beef and dairy products, which are lower in total saturated fat and higher in omega-3s than typical grain-fed beef products (although still relatively small amounts compared to oily fish).
At the store: Grass-fed beef is most commonly sold by natural foods retailers and at farmer’s markets. Check for other sources at eatwild.com. Dairy products from grass-fed cows are increasing in availability, including Kalona Super Natural brand at kalonasupernatural.com.
In the kitchen: Grass-fed beef is leaner and more vulnerable to overcooking. It’s better cooked on the rare side, but if you like your meat well done, brush it with extra virgin olive oil before grilling. Or tenderize and marinate it before cooking, or cook it in a sauce—and dial down the temperature about 50 degrees Fahrenheit.
NOT-SO-UNHEALTHY SATURATED FATS: Lauric Acid Fat – Coconut Oil
The potential merits and harms of coconut oil are being hotly debated. The Academy of Nutrition and Dietetics recently stated that consuming coconut oil is not recommended, due to the fact that it raises total cholesterol levels. However, some fats experts point out that the types of saturated fat in coconut oil, including lauric acid, increase HDL (good) cholesterol a lot more than LDL (bad) cholesterol, thus improving your overall cholesterol ratio. For people with elevated cholesterol and weight concerns, the safest route is likely to use small amounts of coconut flakes, rather than the isolated oil, which is more concentrated in fat and calories.
At the store: Skip sweetened shredded coconut in favor of unsweetened coconut flakes, often sold in the health section of supermarkets. If your cholesterol and weight are in check, it’s likely fine to use virgin coconut oil in small amounts for flavor but not as your main cooking oil.
In the kitchen: Toss a tablespoon of coconut flakes into the blender with your favorite homemade smoothie ingredients, or sprinkle them on baked goods or oatmeal. Try some of our favorite coconut recipes, too.
VERY BAD FATS: Trans Fat – Margarine and Shortening
When margarine came into popular use several decades ago, it was endorsed by medical experts as a healthier alternative to animal fats. Countless research studies later, we now know that the manufactured partially hydrogenated oil (trans fat) that margarine and vegetable shortening contain is anything but heart-healthy, because it raises triglycerides, raises LDL (bad) cholesterol, lowers (HDL) good cholesterol, promotes inflammation, and may worsen insulin resistance.
At the store: The American Heart Association advises buying liquid margarine or soft margarine in a tub rather than stick margarine, which is the worst trans fat offender. If you prefer real butter, go for the whipped kind, which has air beaten into it to cut fat and calories in half compared with stick butter (and without the undesirable additives of butterlike spreads). Heart-healthy liquid oils, such as olive and avocado, are even better choices.
In the kitchen: If baking, consider swapping part or all of the margarine or shortening with pureed fruit, such as applesauce, pureed pumpkin, or mashed avocado. Mashed avocado is also a healthy alternative for spreading on toast, and olive oil can be drizzled on baked potatoes and other vegetables.
VERY BAD FATS: Trans Fat – Top Processed-Food Offenders
Since 2006, the U.S. Food and Drug Administration has required food manufacturers to provide the amount of artificial trans fat per serving on the Nutrition Facts label, which prompted many companies to cut back on this artery-clogging fat. But you can still find plenty of trans fat in foods, such as in most ready-to-spread frostings, and some frozen cheesecakes and pies, microwave popcorn, refrigerated rolls you pop out of the tube and bake, snack foods, and baking mixes for bars, muffins, cookies, and cakes.
At the store: Check for trans fat in every packaged food, and leave it on the shelf if you see any trans fat grams on the label. If a supermarket has an in-store bakery, avoid products made with vegetable shortening or margarine. Deep-fried foods are another trans fat culprit.
In the kitchen: Consider replacing processed foods containing trans fat with a homemade version you make from scratch, so you can control the fats and other ingredients used.
VERY BAD FATS: Trans Fat – Hidden Partially Hydrogenated Oil
It’s easy to spot trans fat in packaged foods when the grams of trans fat must be listed on the Nutrition Facts panel. But if a food has less than 0.5 grams trans fat per serving, manufacturers are allowed to round the number to 0. The only way you’d know such a food contains trans fat is if you check the ingredients for “partially hydrogenated oil,” which means trans fat is present. Even small amounts are harmful to heart health and should be avoided. In late 2013, the FDA published a proposed rule to ban partially hydrogenated oils (PHO) from general use in processed foods. A final decision—which might take some time, as government regulations do—will come from the FDA after the usual public comment period.
At the store: If a processed food has 0 grams trans fat on the nutrition label, check for partially hydrogenated oil in the ingredients list. It often hides in foods such as peanut butter, snack mixes, boxed meal helpers, boxed potato products, cookies, and granola bars. In many cases you can find a comparable product or different brand made without trans fat.
In the kitchen: Take a look at the ingredients lists of the foods in your pantry that might contain PHO. Make a note to steer clear of these foods and hunt for another brand without PHO in the future.
QUESTIONABLE FATS: Interesterified Oils
For manufacturers, getting rid of trans fat is tricky, because this partially solidified fat imparts desirable characteristics to food products and extends product shelf life. Some companies have been replacing trans fat with oils made more solid through a process called interesterification. Limited evidence suggests interesterified oils might negatively affect cholesterol and blood sugar, but not nearly enough research has been done. Plus, these oils’ health effects may vary depending on the different processes, fats, and oils used in interesterification.
At the store: Some products do have the words “interesterified oil” in the ingredients list, such as some cookies and tortillas, so you can choose an alternate brand if you wish. Some tub margarines also use interesterified oil, but these words aren’t necessarily used in the ingredients list, so it’s difficult to know for sure without contacting the manufacturer.
In the kitchen: Until more is known about interesterified oils, don’t go overboard eating them. Focusing on whole, plant-based foods will help you naturally minimize your exposure to such highly processed fats.
QUESTIONABLE FATS: Genetically Modified (GMO) Oils
It used to be that if plant foods were genetically altered, it was done through plant breeding. Since 1996, however, some foods have been genetically modified through a laboratory process where genes from the DNA of one species are extracted and artificially forced into the genes of an unrelated species. The foreign genes may come from plants, animals, bacteria, or viruses. The majority of GMO crops are engineered to either resist high doses of chemical weed killers or generate their own internal insecticides. Some scientists are also using genetic modification to alter the fats in oils, such as changing soybean oil to contain more omega-3 fats. Though not all scientists agree, the FDA considers GMO foods safe.
At the store: Corn, soybean, canola, and cottonseed oils are commonly genetically modified. If you prefer to avoid GMOs, buy organic versions of these oils, if at all. Organic foods are not allowed to contain GMO ingredients. One leading brand of buttery spreads (Smart Balance) now promotes some of its products as being made with non-GMO oils.
In the kitchen: Although corn, soybean, and canola oil are commonly used in vegetable oils, non-GMO oils, including organic versions of these oils or olive and avocado oils, can easily be substituted in recipes, if you wish.