What Is The Difference Between Saturated and Unsaturated Fats?
From claims to limit its intake or cut it out altogether, it is not uncommon for fat to be misrepresented. However, fat comes in a wide variety of forms, even so-called "healthy fat" that show to offer health benefits. So when it comes to fat types, including saturated and unsaturated fats, what is the difference?
Oh the reputation of fat... From claims to limit its intake or cut it out altogether, it is not too uncommon for fat to be misrepresented. However, fat comes in a wide variety of forms, even including so-called "healthy fat" that show to offer health benefits. So when it comes to fat types, including saturated and unsaturated fats, what is the difference?
Coined of its name based on chemical structure, saturated fats lack any double bonds and are essentially saturated with hydrogen atoms. The saturation provides its physical properties, including being solid at room temperate with a higher melting point and a lesser likelihood to become rancid. A primary, well-recognized example of saturated fat includes butter, as it is solid at room temperature though can soften under warmer conditions. Other common saturated fat sources include:
Particularly high-fat meats, including beef, poultry, and pork. Choosing "lean" or "loin" products can lessen the saturated fat content.
Highly processed and "filler" meats such as bologna, sausage, hot dogs, and bacon are generally a significant source of not only saturated fat, but salt and sodium.
Whole milk and dairy products, including cheese and butter. Skim and "low-fat" options have lesser quantities of saturated fat.
Convenient, pre-packaged snacks often contain saturated fat, primarily based on the addition of butter and oils added during production. Frequently consumed snacks include chips, crackers, cookies, and other pastries.
Though saturated fat is primarily found in animal sources, certain plant oils, such as coconut and palm oils, are significant sources.
Unsaturated fats grant its name from the unsaturation of a carbon structure, related to one or more double bonds. Unsaturated fats provide variable properties based on its chemical configuration, including mono- and polyunsaturated fatty acids, though both are soft or liquid at room temp, display a lower melting point than saturated fats, and become more rancid when exposed to light or oxygen for extended periods of time.
Monounsaturated Fatty Acids
Monounsaturated fatty acids (MUFAs) contain only one double bond in its structure. They are commonly found in oils, including olive, canola, and peanut; along with olives, peanuts, and avocados.
Polyunsaturated Fatty Acids
Unlike monounsaturated fatty acids, polyunsaturated fatty acids (PUFAs) contains two or more double bonds. PUFAs are further broken down into two subtypes, omega-3 and 6 fatty acids:
Omega-3 Fatty Acids
Omega-3 fatty acids, or simply omega-3s, has been a buzzing word across the health world, but for much reason. But despite its casual toss around, many may not realize or understand omega-3s are further broken down into alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). Linolenic acid is primarily found in oils (flaxseed, canola, and walnut), alongside various nuts and seeds. Though EPA and DHA can be synthesized from ALA, recommendations still push for their consumption, including the primary providers of fatty fish, including mackerel, salmon, anchovy, herring, sardines, and tuna. The consumption of omega-3s have considerable benefits to health, including the reduction and management of heart disease, cancer, and rheumatoid arthritis (RA).
Omega-6 Fatty Acids
Like omega-3s, omega-6 fatty acids are also broken down, and include linoleic acid (LA) and arachidonic acid (LA). LA sources are primarily found in vegetable oils (corn, sunflower, safflower, and soybean) while meat is the primary supplier of AA (AA can also be produced from LA). Additionally, consuming more omega-6s over omega-3s may cause negative health consequences, including unhealthy blood lipids.
Which Fat Should You Choose?
In worry of saturated fat causing heart disease, the American Heart Association (AHA) encourages consuming less than 7 percent of total daily calories from saturated fat, translating to no more than 120 calories (or 13 grams) from such sources. However, growing research negates such effects and suggests although saturated fat may increase LDL (or "bad") cholesterol, the type of particles increased are large and light. Small, dense LDL cholesterol is shown to cause hardening of the artery walls, a process known as atherosclerosis, and may even be reduced with saturated fat intake. Additionally, the type of saturated fat poses consideration, as evidence demonstrates whole dairy products may lower heart disease risk while processed meats may just in fact increase it.
Consuming MUFAs has been shown to decrease LDL and total cholesterol levels, though little evidence has indicated its ability to increase HDL (or "good") cholesterol levels. When it comes to PUFAs effect on blood cholesterol, though it has shown to decreased LDL and total cholesterol, it may also decrease beneficial HDL cholesterol. However, health experts consistently lean towards consuming more omega-3s over omega-6s, along with frequently replacing saturated fat sources with unsaturated fats, including oils over butter. But furthermore, even beyond saturated and unsaturated fat, it is well-known trans fats have a direct link to heart disease, and is extremely encouraged to be extinguished within the diet.
Nonetheless, despite their chemical makeup, both saturated and unsaturated fat are equally energy-dense, supplying 9 calories per one gram. Additionally, whole foods are encouraged over highly processed items, including drinking a glass of milk over a hotdog or links of sausage. But aside from dietary fat, meals should be well-rounded with whole grains, lean meats, fruits and veggies, legumes, and other healthy fat sources, and limited or devoid of added sugars, man-made preservatives, and trans fats.
Essential Fatty Acids. Linus Pauling Institute.