Trans fatty acids are formed when a liquid fat is changed into a solid fat through a process called hydrogenation. Many manufacturers use hydrogenated oils as an ingredient because it extends the shelf life and consistency of foods. Trans fat will raise levels of “bad” LDL cholesterol and decrease levels of “good” HDL cholesterol. There are no safe levels of trans fat to eat each day, so try to avoid trans fat completely. Even if a food is advertised as “trans fat free,” it can still contain small amounts of trans fat. Therefore, avoid foods that list partially hydrogenated oils as ingredients. Sources of trans fat include:
Monounsaturated fats. When you dip your bread in olive oil at an Italian restaurant, you're getting mostly monounsaturated fat. Monounsaturated fats have a single carbon-to-carbon double bond. The result is that it has two fewer hydrogen atoms than a saturated fat and a bend at the double bond. This structure keeps monounsaturated fats liquid at room temperature.
Omega-3 fatty acids promote health in several ways. They reduce inflammation and lower the risk of chronic diseases including heart disease, cancer, and arthritis. Omega-3 fatty acids can help lower triglycerides and apoproteins (markers of diabetes), and raise HDL (“good” cholesterol) levels (8). Omega-3 fats are also essential for brain and eye health (9).
What these studies highlight is that when cutting down on saturated fats in your diet, it’s important to replace them with the right foods. For example, swapping animal fats for vegetable oils—such as replacing butter with olive oil—can help lower your cholesterol and reduce your risk for disease. However, swapping animal fats for refined carbohydrates-such as replacing your breakfast bacon with a bagel or pastry-won’t have the same benefits. That’s because eating refined carbohydrates or sugary foods can have a similar negative effect on your cholesterol levels, your risk for heart disease, and your weight.
Most nuts and seeds are good healthy-fat choices, but almonds and walnuts are at the top of many experts’ lists as a great part of a heart-healthy diet to lower high cholesterol. “Almonds and walnuts are quick, delicious, and easy for a mid-morning or mid-day snack,” says Maria Haisley, RD, a clinical dietitian at Elkhart General Hospital in Indiana. “Make your own trail mix using your favorite ingredients or simply add to salads. Try using ground almonds as a coating on baked chicken or fish.” This chicken fingers recipe is a delicious way to do just that.
The reality is, not all fats are created equal. Some are downright bad (like trans fats in margarines), some are misunderstood (like the saturated fat, lauric acid), and some fats are health heroes (like omega-3s). And, don’t get us wrong, eating foods that are packed with the wrong kinds of fat will make you fat, but with all the omegas, and monos, and polys out there, it can be kind of confusing which are which. To make things easier for you, we here at Eat This, Not That! found the best foods with good fats that you can add to your diet. But before you go off on a high-fat binge, remember that—like all food—even these healthy fats should be consumed in moderation.
Plus, eating a good variety of foods high in fat can also boost brain function. Loading up on the healthy fat foods can soothe inflammation and promote blood flow to the brain to enhance cognitive function. In particular, medium-chain fatty acids, omega-3 fatty acids and unsaturated fats play a critical role in brain function and development. (11, 37, 38)
Studies have found that avocados can lower levels of bad LDL cholesterol, boost anti-inflammatory properties, and improve vascular health. It’s very simple to add avocados to just about any salad. “Simply think portion control when integrating it into a weight-loss plan,” says Warren. If you’re concerned about how much fat you’re consuming or simply don’t prefer avocado on its own, try whipping up an avocado-based dressing. Toss an avocado, some Greek yogurt, and seasonings (we like fresh cilantro and parsley) into a blender and enjoy.
Fat, fat, fat! Would all of our weight loss problems be solved if we just eliminated fat from our diets? Unfortunately, it's not that simple. We actually need fats -- can't live without them, in fact. Fats are an important part of a healthy diet: They provide essential fatty acids, keep our skin soft, deliver fat-soluble vitamins, and are a great source of energizing fuel. But it's easy to get confused about good fats vs. bad fats, how much fat we should eat, how to avoid artery-clogging trans fats, and the role omega-3 fatty acids play in heart health.
Following a high monounsaturated fat diet can be beneficial for improving insulin sensitivity in both individuals who have, or do not have high blood sugar levels. One study found that following a high monounsaturated fat diet for three months managed to improve insulin sensitivity by up to nine percent (14). This was followed by another study which found participants who had metabolic syndrome and followed a high monounsaturated fat diet for twelve weeks had a significant reduction in insulin resistance (15).
Although for several decades the American Heart Association and other health organizations have advised people to reduce their saturated fat intake, studies have consistently failed to show a link between saturated fat and heart disease. Because of this, the role of natural saturated fats in a healthy diet is now being reconsidered. All in all, saturated fats appear to be neutral in their health effects.
Today’s Basics topic is all about fat! We’ve covered other macronutrients here on the Nutrition Stripped blog such as carbohydrates, protein, and digestion, and now the list is growing! Out of all the macronutrients, people have the most misconceptions about by fat! Today I’m sharing a breakdown of food sources of healthy fats, the function of fat in the human body, how fats are digested, and how our bodies store fat. If I haven’t lost you yet, keep reading on to learn the basics of healthy fat from a dietitian’s point of view. Let’s jump in!
All foods containing fat have a mix of specific types of fats. Even healthy foods like chicken and nuts have small amounts of saturated fat, though much less than the amounts found in beef, cheese, and ice cream. Saturated fat is mainly found in animal foods, but a few plant foods are also high in saturated fats, such as coconut, coconut oil, palm oil, and palm kernel oil.
Fat droplets start to pass through the duodenum where bile acids are added (bile acids are from cholesterol in the liver and stored in the gall bladder). Bile acids are really cool because they act like soap breaking and emulsifying the fat droplets and making them into even smaller droplets. I like to use the visual of washing a pan with grease on it with soap, at first the grease barely comes off, but with a little muscle and scrubbing with soap the detergent breaks up the fat and grease into very small particles until it’s gone.
Dietary fat has been in the limelight since the 1950s, when researcher Ancel Keys conducted a study analyzing the diet patterns of seven different countries as well as their respective rates of heart disease. At the conclusion of the study, he found that higher levels of serum cholesterol were associated with a higher risk of heart disease and believed that a higher intake of foods high in saturated fat was to blame. (44)
Additionally, coconut and the different varieties of coconut may have antimicrobial properties, provide benefits to gut and digestive health (here and here), as well as help increase skin moisture and integrity (here, here, and here). For even more studies to read the science behind coconut oil/medium chain triglycerides, feel free to check out one of my favorite resources here.
That said, dietary fat plays a significant role in obesity. Fat is calorie-dense, at 9 calories per gram, while carbs and protein have only 4 calories per gram, and alcohol has 7 calories per gram. It's easy to overeat fats because they lurk in so many foods we love: french fries, processed foods, cakes, cookies, chocolate, ice cream, thick steaks, and cheese.
Healthy fats are unsaturated fats that are found in fatty fish like salmon, avocados, nuts and seeds, plant oils that are liquid at room temperature like olive oil, and coconut oil. Coconut oil is contested as a healthy fat because it is a saturated fat, but because the majority of its fat content is medium-chain triglycerides (MCT), I consider them an exception.
It’s easy to see the similarities between nuts and nut butters, but you’d be surprised to note that not all nut butters will be good sources of healthy fats. It’s important to check out the nutrition labels on jars of regular and reduced-fat nut butters. You’ll see a few differences: While the reduced-fat butters have—surprise!—less fat, they also have more sugar and salt. Not so good when you’re trading healthy monounsaturated fats that help lower your sensitivity to insulin for insulin-raising sugars. Make sure you go natural and minimalist. Non-natural nut butters can contain the bad trans fat: partially hydrogenated oils.
And if you're thinking fish-oil capsules will help you avoid the contamination risks of fresh fish, think again. Because supplements are not regulated in the U.S., Sandon says, some may contain concentrated amounts of the same toxins found in fresh fish. And because the oil is so concentrated, the supplements can also produce an unpleasant body odor.
Nine moderately athletic men took either spirulina capsules or a placebo for four weeks in a study printed in Medicine & Science in Sports & Exercise. Afterward, the men who had taken spirulina supplements were able to run 30 percent longer than the men who had taken a placebo and burned 11% more fat during a run! Fueling up before your run? Check out our exclusive report, Eat This, Not That! For Runners.
However, many experts disagree with the report’s conclusions on a few fronts. First, the link is based on the reasoning that saturated fat raises total cholesterol levels, but many studies suggest the link between higher cholesterol numbers and heart disease risk has been overstated. And while LDL is often referred to as “bad” cholesterol, there are different types of LDL, and the total number may be less important than the composition of the actual particles. Small, dense particles are inflammatory and associated with heart disease risk, while larger particles are not.
Several studies explore and show the this type of saturated fat in coconut does not negatively affect cholesterol levels nor overall heart health like we were once told. Some studies have shown coconut oil moderately increases metabolic rate, which is often a “selling” point that it helps boost your metabolism and contribute to fat loss or weight control. I’ll let these studies here, here, and here tell you what we do know.