Main Difference – Monounsaturated vs Polyunsaturated Fats
Many people believe that all fats are bad, and they make you obese. But, this is a false assumption; you need a certain amount of fat in your daily diet to keep your body healthy. There are two types of unsaturated fats known as monounsaturated and polyunsaturated fats; one of these types is healthier than the other. Therefore, it is important to understand the difference between monounsaturated and polyunsaturated fats to select the healthy option. The fatty acids in monounsaturated fats have single bonds and only one double bond whereas fatty acids in polyunsaturated fats have single bonds and more than one double bond. This is the main difference between monounsaturated and polyunsaturated fats. Both monounsaturated and polyunsaturated fats are associated with positive health outcomes, and these fats can help keep your body functioning healthily. This article explores the differences in chemical and physical properties of monounsaturated and polyunsaturated fats.
What is Monounsaturated Fat
Monounsaturated fat is a fat molecule that comprises of two types of smaller molecules known as mono-glyceride and fatty acids. These fatty acids have only one double bond. Fatty acids are made of long chains of carbon (C) atoms, and some of these carbon atoms are connected by single bonds (-C-C-). Fatty acids containing double bonds can react with hydrogen to form saturated fats.
Olives and olive are a source of Monounsaturated fats
What is Polyunsaturated Fat
Polyunsaturated fat is a fat or fatty acid that has both single bonds and double bonds. Nuts, seeds, algae, leafy greens, fish, and krill are considered as rich sources of polyunsaturated fats. These fats are highly susceptible to oxidation. When polyunsaturated fat-rich foods are exposed to the atmosphere, they are susceptible to further oxidation and rancidity.
Sunflower seeds are rich in Polyunsaturated Fats.
Difference Between Monounsaturated and Polyunsaturated Fats
The differences between monounsaturated and polyunsaturated fat can be classified into following categories.
Definition
Monounsaturated Fat: Monounsaturated fat is a fat or fatty acid having only one double bond in their molecular structure.
Polyunsaturated Fat: Polyunsaturated fat is a fat or fatty acid that has more than one double bond in their structure.
Melting Temperature
Monounsaturated Fat: Monounsaturated fats have a higher melting point than polyunsaturated fatty acids. They are liquids at room temperature and semisolids or solids when refrigerated.
Polyunsaturated Fats: Polyunsaturated fats have a lower melting point than monounsaturated fatty acids. Due to their chemical structure, unsaturated fats have a liquid consistency at room temperature.
Most Common Examples
Monounsaturated Fat: Palmitoleic acid (16:1 n−7), cis-vaccenic acid (18:1 n−7) and oleic acid (18:1 n−9) are common examples.
Oleic Acid
Polyunsaturated Fat: Omega-3 fatty acids such as eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) and Omega-6 fatty acids such as Gamma-linolenic acid (GLA), Arachidonic acid (AA) and Dihomo-gamma-linolenic acid (DGLA) are examples.
Linoleic acid
Most Common Sources
Monounsaturated Fat: Common sources include,
- Cooking oils such as olive oil, sesame oil, and canola oil
- Peanut butter
- Nuts such as peanuts and cashews
- Avocados
- Olives
- Sesame seeds
- Healthy spreads that are labeled “ high oleic”
- Red meat
- Whole milk products
- Cereals and related products such as corn oil, popcorn, whole grain wheat
Polyunsaturated Fat: Polyunsaturated fat can be found in
- Seeds such as sunflower seeds, pumpkin seeds, flax seeds and chia seeds
- Cooking oils including corn oil, safflower oil, and soybean oil
- Nuts such as pine nuts and walnuts
- Fatty fish including salmon, mackerel, herring, and tuna
- Algae
Susceptibility to Oxidation
Monounsaturated Fat: When monounsaturated food is exposed to the atmosphere, it is susceptible to further oxidation and rancidity.
Polyunsaturated Fat: When polyunsaturated foods are exposed to the atmosphere, they are susceptible to further oxidation and rancidity and its rate of oxidation is high compared to monounsaturated fat.
Health Aspects
Monounsaturated Fat: Monounsaturated Fats are associated with various health benefits.
- Reduce the risk of cancer development, cardiovascular disease, reduce LDL cholesterol (Bad cholesterol) and increase HDL cholesterol (good cholesterol)
- Reduce the risk of rheumatoid arthritis
Polyunsaturated Fats: Polyunsaturated fats are associated with various health benefits.
- Reduce the risk of cancer development
- Prevent cardiovascular disease, platelet aggregation and hypertension
- They have the anti-inflammatory properties and lower markers of inflammation in the blood such as C-reactive protein and interleukin 6.
- Supplements are given to autism children and Alzheimer’s disease patients
- Reduce the risk of rheumatoid arthritis
- Help to control cholesterol levels
Inflammatory Properties
Monounsaturated Fat:Monounsaturated Fats have anti-inflammatory properties which is good for human health.
Polyunsaturated Fats:Polyunsaturated Fats have both anti-inflammatory and pro-inflammatory effects. As an example, ω-6 fatty acids are associated with pro-inflammatory effects that can cause negative health outcomes.
In conclusion, both monounsaturated and polyunsaturated fats have several roles in the human body. In addition to being the principal component of stored fat, they also serve as important building blocks of cell membranes and regulate inflammatory processes. In nutritional standpoint, both monounsaturated and polyunsaturated fats are better than saturated fat. But they are equally energy-dense molecules so you should consume both in self-control level as these can incorporate calories to the daily diet.
References
Okuyama, H., Ichikawa, Y., Sun, Y., Hamazaki, T. and Lands, W.E.M. (2006). ω3 Fatty Acids Effectively Prevent Coronary Heart Disease and Other Late-Onset Diseases – The Excessive Linoleic Acid Syndrome. In Okuyama, H. Prevention of Coronary Heart Disease. World Review of Nutrition and Dietetics. pp. 83–103.
Ricciotti, Emanuela and FitzGerald, Garret, A. (2011). Prostaglandins and inflammation. American Heart Association Journal, 31(5): 986–1000.
Scorletti, E. and Byrne, C. D. (2013). Omega-3 fatty acids, hepatic lipid metabolism, and nonalcoholic fatty liver disease. Annual review of nutrition, 33(1): 231–48.
Vafeiadou K, Weech M, Altowaijri H, et al. Replacement of saturated with unsaturated fats had no impact on vascular function but beneficial effects on lipid biomarkers, E-selectin, and blood pressure: results from the randomized controlled Dietary Intervention and VAScular function (DIVAS) study. Am J Clin Nutr. 2015 Jul;102(1):40-8.
De Souza RJ, Mente A, Maroleanu A, et al. Intake of saturated and trans unsaturated fatty acids and risk of all-cause mortality, cardiovascular disease, and type 2 diabetes: systematic review and meta-analysis of observational studies. BMJ 2015; 351:1-16.
Image Courtesy:
“Olive oil” by Oregon State University (CC BY-SA 2.0) via Flickr
“Gfp-sunflower-seeds” By Yinan Chen – www.goodfreephotos.com (gallery, image), (Public Domain) via Commons Wikimedia
“Oleic-acid-based-on-xtal-1997-2D-skeletal” By Ben Mills – Own work, (Public Domain) via Commons Wikimedia
“Linoleic acid shorthand formula” By Wolfgang Schaefer – created with Microsoft (R) Paint 5.1 (Public Domain) via Commons Wikimedia
