Fats are essential to good health and you need to consume some every day for your body processes to work efficiently. Fat is a necessary nutrient for using fat-soluble vitamins (A, D, E, K) and a dense energy source. Additionally, the fat in the diet helps with growth, brain and nervous system function, healthy skin, bone protection, insulation, and works as a cushion for your organs. But not all fats are the same or provide the same health benefits. All foods containing fats have a varying mixture of saturated, monounsaturated and polyunsaturated fats. The Academy of Nutrition and Dietetics recommends that healthy adults should consume fats at a range of 20-35 percent of their total daily energy intake. They also recommend an increased consumption of n-3 polyunsaturated fatty acids and limited intake of saturated and trans fats. All fats provide 9 calories per gram, but depending on if they are in concentrated oil form or solid, the per tablespoon calories change. On average, a tablespoon of oil is about 120 calories. Whether the fats you eat are in liquid form like oil, or solid form like margarine, they become broken down by your body into fatty acids and glycerol. Your body takes these and forms other lipids in the body and stores the remainder in the form of a triglyceride.
But what does this recommendation really mean for you? How do you tell the difference between saturated fats, trans fats or unsaturated fats?
Fats can be saturated or unsaturated, depending on how many hydrogen atoms link to each carbon in their chemical chains. The more hydrogens attached to the chain, the more saturated the fat will be. If there are hydrogen atoms missing, the fatty acid is considered unsaturated.
Saturated Fats are fatty acids that have hydrogens at all the points on their chemical chain. They are associated with triggering the liver to make more total cholesterol and more LDL cholesterol. However, recently, there has been a big move to re-analyze if saturated fat is actually as bad as previously thought. Saturated fats, like palmitic acid or steric acid, seem to have different effects on LDL cholesterol circulating in your blood. Some question if enough research has been done to determine if diets low in saturated fat have any benefit or reduce your risk of heart disease. More research will be needed to understand the effect of saturated fat in the diet, however the majority of nutrition experts, including the Academy of Nutrition and Dietetics, still recommend keeping saturated fat to a minimum in the diet.
- Whole milk
- Coconut oil
- Palm oil
Unsaturated fats fall into two categories, monounsaturated and polyunsaturated. Monounsaturated and polyunsaturated fats are considered to be more health beneficial than saturated fats or trans fats.
Monounsaturated fatty acids (MUFAs) are fatty acids that are missing one hydrogen pair on their chain. They are associated with lowering LDL cholesterol, total cholesterol and at the same time increasing the production of the "good" cholesterol, HDL cholesterol. These fats are usually liquid at room temperature.
- Sunflower oil
- Canola oil
- Olive oil
- Peanut oil
- Macadamia nuts
Polyunsaturated fatty acids (PUFAs) are missing 2 or more hydrogen pairs on their fatty acid chains. They trigger lower blood/ serum cholesterol as well as lower LDL production. However, they have also been shown to lower HDL production. These fats are usually liquid at room temperature.
- Flaxseed oil
- Corn oil
- Sesame oil
- Sunflower seeds and sunflower oil
- Fatty fish, i.e. Salmon
Some specific polyunsaturated fatty acids of a different structure with important health benefits include omega-3 fatty acids and omega-6 fatty acids.
Omega-3s are found in meat sources. In non-meat sources, our bodies' process alpha-linolenic acid into usable omega-3s. These fats are considered especially health beneficial because they are linked with improving immunity, rheumatoid arthritis, vision, brain function, and heart health. Omega-3s have been shown to lower both triglyceride levels in the body and total cholesterol levels. It is recommended that you consume foods rich in omega-3s frequently.
- Seafood- High fat mackerel, albacore tuna, sardines, salmon, lake trout
- Flaxseed oil
- Soybean oil
- Canola oil
Omega-6 fatty acids found in vegetable oils are also PUFAs. These are also associated with reducing cardiovascular disease risk by lowering LDL cholesterol levels. However, they may also lower HDL levels.
- Most vegetable oils
- Sunflower seeds
- Pine Nuts
Trans fats are created when food manufacturers extend the shelf life of foods with fats in them by adding hydrogen to their chemical makeup. Adding hydrogen makes the fats in the food firmer and more saturated, thereby delaying rancidity and extending freshness. By adding hydrogens, the food becomes more saturated and hydrogenation results in trans fats. Sadly, trans fats are linked to increasing total cholesterol and LDL cholesterol, as well as lowering HDL cholesterol. You find small amounts of trans fats naturally occurring in beef, pork, butter and milk, however these trans fats have different effects from the man-made trans fats and are not associated with having the same effects on cholesterol levels.
Emily DeLacey MS, RD is a Registered Dietitian and currently working in Jamaica as a HIV/ AIDS Prevention Specialist. She attended Central Washington University for her Bachelor's Degree in Science and Dietetics and continued on after her internship to Kent State University for her Master's Degree in Science and Nutrition, with a focus on public health and advocacy. She served as a U.S. Peace Corps Volunteer in Malawi 2012-2014 working as a Community Health Advisor in a rural village, immersing in the joys of life without electricity or running water. She has been to 20+ countries and 47 of the 50 states in the US. Traveling, adventuring and experiencing new cultures has made her a passionate advocate for the equality of nutrition and wellness for all people.