Fat came under scrutiny in the 1960s when the sugar industry paid Harvard researchers to publish a review on sugar, fat, and heart disease. The sugar industry funded the research to cover up warning signs, which emerged in the 1950s, that sugar caused heart disease (1). Shifting the blame away from sugar, the researchers singled out saturated fat as the cause of heart disease.
All digestion first takes place in the mouth from chewing and saliva beginning to break down food. After you eat a fat-containing food, such as almonds, you first break down the food in your mouth. Next, it goes to your stomach where those solid pieces of almond are further broken down via stomach acid (2). Fats actually hang out in the stomach for quite a bit which is one reason for why fat keeps you feeling fuller longer. Depending on the volume of food and components of food, healthy fats may keep you feeling full for hours.
Ideally, you’ll want to consume minimally-processed foods that are full of heart-healthy, polyunsaturated omega-3 fatty acids (ALA, DHA, and EPA), monounsaturated fats (OEA), and the trans fat conjugated linoleic acid (CLA), as well as some medium-chain saturated fats like stearic acid and lauric acid. On the other hand, stick to foods that have low levels of omega-6 fatty acids and other saturated fats (palmitic acid), and zero manmade trans fats (partially hydrogenated oil). According to the Dietary Guidelines, an easy way to do this (besides following this list) is to lessen consumption of the top sources of saturated fats like pizza, burgers, meats, and processed snacks and sweets.
Eggs are an inexpensive and easy source of protein. People often think egg whites are a healthier option than whole eggs because they contain less fat, but while it's true that the egg yolk contains some fat, it's also packed with important nutrients. One whole egg contains 5 grams of fat, but only 1.5 grams are saturated. Whole eggs are also a good source of choline (one egg yolk has about 300 micrograms), an important B vitamin that helps regulate the brain, nervous system, and cardiovascular system. As for the cholesterol? The latest nutrition research has found that eating cholesterol doesn't raise our blood cholesterol. In fact, research has linked moderate egg consumption to improved heart health.
Some forms of saturated fats, such as coconut oil, are comprised of medium-chain fatty acids, which are easier to metabolize than the long-chain fatty acids found in animal fats. This makes coconut oil much healthier for you. In fact, coconut oil has a whole host of other good properties, including lauric acid which is antiviral and antibacterial, and caprylic acid which is antifungal.
Trans fats are typically found in highly-processed fatty foods such as crackers, cakes, donuts and pastries. Studies show that eating this unhealthy type of fat can have detrimental effects on health; one study in the New England Journal of Medicine even reported that each 2 percent increase in calories consumed from trans fats nearly doubled the risk of coronary heart disease. (39)
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:
Another victim of the war on fat, butter has recently experienced a comeback as the benefits of butter become more widely known. The omega-6 and omega-3 fatty acids found in butter help your brain function properly and improve skin health. More importantly, these two fatty acids are considered essential, meaning the body needs them but can’t produce them on its own; instead, they must be consumed from food sources. Butter is also rich in fat-soluble vitamins and trace minerals, including beneficial selenium, a powerful antioxidant. (9)
Plus, subsequent studies have also found that picking the right types of fat and adding plenty of high-fat foods to your diet could actually bring some big benefits to your health. One study in the New England Journal of Medicine found that when subjects ate either a Mediterranean diet, low-fat diet or low-carb diet, those following a high-fat, low-carb meal plan not only lost the most weight but also drastically reduced their bad cholesterol levels. (2)
Additionally, adding plenty of nutritious fats to your diet is just one piece of the puzzle when it comes to health. Be sure to round out your diet with plenty of protein foods as well as a good variety of fruits, vegetables, legumes and whole grains to make sure you’re meeting your nutritional needs, and pair a well-balanced diet with regular physical activity and a healthy lifestyle for best results.