Q: Please explain what polyunsaturated and monounsaturated fats are.
A: Fats, — of which there are several types — are comprised of varying amounts of fatty acids. It’s the type and quantity of the fatty acid in the foods we eat that determines the effect it will have on health. Those fatty acids found in foods that are plant-and-animal based are known as dietary fats. Fat is essential to health, supporting numerous bodily functions. However, keep in mind that fats are high in calories and even small amounts consumed can add up quickly. As we all can appreciate, if a person consumes more than needed, weight gain will follow.
Let’s begin with fats that are considered good for us, specifically those that are polyunsaturated and monounsaturated. Polyunsaturated fats are fats that have more than one double-bonded carbon in the molecule. They are commonly found in plant-based foods such as walnuts and sunflower seeds, in fish such as salmon, mackerel, trout and herring, and in safflower, corn and soybean oils. In moderation, they are good for us. They are in liquid form when at room temperature and when chilled. Eating foods rich in polyunsaturated fats may decrease a person’s risk of having heart disease and type 2 diabetes and can improve blood cholesterol levels.
Monounsaturated fats are also fats that have one double-bonded carbon in the molecule. They differ from polyunsaturated fats because they are generally in a liquid state at room temperature but begin to turn solid when chilled. They are found in numerous foods and oils. Again, eating foods rich in monounsaturated fats in moderation may decrease a person’s risk of developing heart disease, may benefit insulin levels which can be particularly helpful if a person has type 2 diabetes, and improve blood cholesterol levels.
Then there are omega-3 fatty acids we read and hear about, so often. One type of polyunsaturated fat is comprised mainly of omega-3 fatty acids found in some fatty fish and in supplement form. Omega-3s are believed to lower the risk of coronary artery disease in individuals and may be very beneficial to the heart. This particular fat is found in some plant sources; however, the body can’t convert it as well as it can omega-3s from fish. Those fish high in omega-3 fatty acids are salmon, sardines, herring, tuna, and mackerel. Plant sources include walnuts, butternuts, sunflowers, and ground flaxseed. Oils include soybean, canola and flaxseed.
And now, on to those that are potentially harmful – saturated and trans fats. Saturated fat primarily comes from such products as red meat, full-fat (not skim or low-fat) dairy products and poultry. Saturated fats are known to raise blood cholesterol and low-density lipoprotein levels that may, in turn, increase a person’s risk of developing cardiovascular disease and type 2 diabetes. Trans fats are chemically altered and man-made through hydrogenation. They occur naturally within the body in small amounts. Oils of this nature don’t tend to spoil or turn rancid as quickly. That’s the good news. On the downside, research has found partially hydrogenated trans fats may increase bad cholesterol levels known as LDL, while lowering good cholesterol levels known as HDLs.
Individuals interested in consuming a healthful diet should select foods that contain polyunsaturated and/or monounsaturated fats and pass on saturated and trans fats. Packaged products contain ingredient panels that are relatively easy to read for most. Make better choices and reduce your risk of unwanted medical issues. You’ll be glad you did.
