Even though fat has been proclaimed the Darth Vader of food, it also provides energy, and aids in growth and development. The key, experts claim, is focusing on the good fats (monounsaturated and polyunsaturated) and eliminating the bad fats (saturated and trans). If you’re confused about which fats are good and which are bad, you’re not alone. In fact, according to a survey released by the International Food Information Council, 75 percent of people knew they should be eating less saturated and trans fat, but a troubling 42 percent incorrectly assumed they should eat less polyunsaturated fat too.
An easy way to digest the information: “If it walked before it arrived on your plate, it’s probably chock-full of saturated fat (red meat, dark-meat chicken, bacon, etc.),” says Kristin Kirkpatrick, MS, RD, manager of disease reversal at the Cleveland Clinic. “If it swam before it hit your plate, you’re probably getting some good fats such as polyunsaturated fats.” Another clue: If it’s solid at room temperature, it’s probably bad fat, and if it’s liquid at room temperature, it’s probably good.
Regardless of whether the fat you eat is good or bad, all types of fat have nine calories per gram. So, while a salmon fillet may be good for your heart and a cheeseburger may be bad, either one will wreak havoc on your hips if you eat too much. The American Heart Association recommends limiting fat to 30 percent of total daily calories. If you’re eating 2,000 calories a day, that’s about 65 grams of total fat — and only 7 percent of that should come from saturated (aka solid) fats (16 grams, based on a 2,000-calorie diet). The AHA also advises restricting the amount of trans fats you eat to less than 1 percent of your total daily calories (two grams, based on a 2,000-calorie diet), but we suggest cutting it out completely.
Here’s how to identify the good, the bad and the ugly fats in your daily diet.
Studies show that good fats, including polyunsaturated (in fish, walnuts and canola oil) and monounsaturated fats (in olive oil, peanut oil, almonds and avocadoes), help lower cholesterol levels and prevent a variety of chronic diseases ranging from cancer to stroke. “Good fats actually lower your risk of heart disease by reducing the LDL (bad) cholesterol levels in the blood,” says Ann Yelmokas McDermott, PhD, MS, director of STRIDE, a center for translational research, and associate professor of nutrition at Cal Poly, San Luis Obispo. In fact, research shows that perhaps the most healthful polyunsaturated fats, omega-3s, help prevent irregular heartbeats, reduce plaque buildup in the arteries and keep blood sugar levels in check — all of which help reduce the risk of heart disease.
“Omega-3 and omega-6 fatty acids are polyunsaturated fats, and they’re both essential, meaning the body cannot make them,” McDermott says. “You have to get them from food.” The best source: fish. Loaded with essential omega-3 fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), fish, as part of a heart-healthy diet, can slash your risk of dying from heart disease. When possible, opt for fatty fish like salmon, mackerel and sardines since they contain more omega-3s than other varieties.
But even if you don’t like fish, it’s easier than ever to get omega-3s on your plate. Due to the overwhelming evidence of health benefits associated with omega-3s, food manufacturers have begun fortifying everything from eggs to orange juice with the healthful fats. And of course they’re also available in supplement form. Other foods such as canola, walnut, flaxseed and their oils also contain omega-3 fatty acid in the form of alpha-linolenic acid (ALA).
Saturated fats have held the same low level on the fat totem pole for decades. Known to clog arteries and increase the risk for diseases ranging from cancer to diabetes, saturated fat is the cornerstone of most animal-based foods (think fatty beef, pork, lamb, butter and cream). And while Kirkpatrick’s advice for detecting saturated fat (i.e., it walked before arriving on your plate) is usually a slam dunk, there are some caveats. Plant-based versions of saturated fat are lurking in countless processed foods and snacks. Scan the ingredient list of your favorite confections and you’ll probably see oils like palm kernel, palm, cottonseed and coconut on the list. They too contain saturated fat.
Trans fats started out innocent enough. Scientists were looking for an alternative to saturated fat that would impart a similar flavor, texture and overall appeal. They decided to take healthy oils and make them solid using a process called hydrogenation. The result created crisp French fries, perfectly glazed donuts and flaky piecrusts. But by taking away the fluid properties of the oil, they created a fat that’s even more rigid than saturated fat. “We’re finding now that trans fat has an even worse cardiovascular impact than butter,” McDermott says. In one study, Boston researchers analyzed blood samples from nurses and found that those who consumed the most trans fat had triple the risk of developing coronary heart disease than those who consumed the least. Saturated fat also increased the risk, but not nearly as much.
Like saturated fats, trans fats lead to increases in cholesterol, and that boosts your risk of heart disease and stroke. Even more troubling, trans fats raise your LDL (bad cholesterol) and lower your HDL (good cholesterol), putting you at an even greater risk for heart disease and stroke, Kirkpatrick says. HDL helps remove excess LDL from the blood. Trans fats also lead to inflammation, which is linked to many health conditions, such as diabetes and dementia.
Used in many packaged foods — cookies, crackers, cakes, cereals, soups and salad dressings — trans fats can be identified by the words “partially hydrogenated” and “hydrogenated” in the ingredient list. Even a product that’s labeled “trans-fat-free” contains trans fat if the ingredient list includes the word hydrogenated. “Marketers can claim a product is ‘trans-fat-free’ as long as it has less than 0.5 grams per serving,” Kirkpatrick says. Eat four servings and you’re up to two grams of trans fat — the maximum amount allotted for an entire day.