Monounsaturated fat explained

In biochemistry and nutrition, a monounsaturated fat is a fat that contains a monounsaturated fatty acid (MUFA), a subclass of fatty acid characterized by having a double bond in the fatty acid chain with all of the remaining carbon atoms being single-bonded. By contrast, polyunsaturated fatty acids (PUFAs) have more than one double bond.

Molecular description

Monounsaturated fats are triglycerides containing one unsaturated fatty acid. Almost invariably that fatty acid is oleic acid (18:1 n-9). Palmitoleic acid (16:1 n-7) and cis-vaccenic acid (18:1 n-7) occur in small amounts in fats.

Fatty acid component (mole %) of selected fats^[1]

fat source	saturated		doubly unsaturated	tri unsaturated
	60–65		1–3	trace
	23–30		45–58	trace
	10–15		40–60	trace
	8–11		14–20	51–56
	11–17		49–57	6–11
	12–17		39–44	trace
	36–48		10–12	1
	43–64		2–6	1
	45–67		3–10	trace

Health

Studies have shown that substituting dietary monounsaturated fat for saturated fat is associated with increased daily physical activity and resting energy expenditure. More physical activity was associated with a higher-oleic acid diet than one of a palmitic acid diet. From the study, it is shown that more monounsaturated fats lead to less anger and irritability.^[2]

Foods containing monounsaturated fats may affect low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol.

Levels of oleic acid along with other monounsaturated fatty acids in red blood cell membranes were positively associated with breast cancer risk. The saturation index (SI) of the same membranes was inversely associated with breast cancer risk. Monounsaturated fats and low SI in erythrocyte membranes are predictors of postmenopausal breast cancer. Both of these variables depend on the activity of the enzyme delta-9 desaturase (Δ9-d).^[3]

In children, consumption of monounsaturated oils is associated with healthier serum lipid profiles.^[4]

The Mediterranean diet is one heavily influenced by monounsaturated fats. In the late 20^th century, people in Mediterranean countries consumed more total fat than Northern European countries, but most of the fat was in the form of monounsaturated fatty acids from olive oil and omega-3 fatty acids from fish, vegetables, and certain meats like lamb, while consumption of saturated fat was minimal in comparison.A 2017 review found evidence that the practice of a Mediterranean diet could lead to a decreased risk of cardiovascular diseases, overall cancer incidence, neurodegenerative diseases, diabetes, and early death.^[5] A 2018 review showed that the practice of the Mediterranean diet may improve overall health status, such as the reduced risk of non-communicable diseases. It also may reduce the social and economic costs of diet-related illnesses.^[6]

Diabetes

Increasing monounsaturated fat and decreasing saturated fat intake could improve insulin sensitivity, but only when the overall fat intake of the diet was low.^[7] However, some monounsaturated fatty acids (in the same way as saturated fats) may promote insulin resistance, whereas polyunsaturated fatty acids may be protective against insulin resistance.^{[8] [9]}

Sources

Monounsaturated fats are found in animal flesh such as red meat, whole milk products, nuts, and high fat fruits such as olives and avocados. Algal oil is about 92% monounsaturated fat. Olive oil is about 75% monounsaturated fat.^[10] The high oleic variety sunflower oil contains at least 70% monounsaturated fat.^[11] Canola oil and cashews are both about 58% monounsaturated fat. Tallow (beef fat) is about 50% monounsaturated fat.^[12] and lard is about 40% monounsaturated fat. Other sources include hazelnut, avocado oil, macadamia nut oil, grapeseed oil, groundnut oil (peanut oil), sesame oil, corn oil, popcorn, whole grain wheat, cereal, oatmeal, almond oil, sunflower oil, hemp oil, and tea-oil Camellia.^[13]

See also

• High density lipoprotein
• Fatty acid synthesis

External links

• Fats (Mayo Clinic)
• The Chemistry of Unsaturated Fats

Notes and References

1. Book: 10.1002/14356007.a10_173 . Fats and Fatty Oils . Ullmann's Encyclopedia of Industrial Chemistry . 2000 . Thomas . Alfred . 978-3-527-30385-4 .
2. Kien CL, Bunn JY, Tompkins CL, Dumas JA, Crain KI, Ebenstein DB, Koves TR, Muoio DM . Deborah Muoio. Substituting dietary monounsaturated fat for saturated fat is associated with increased daily physical activity and resting energy expenditure and with changes in mood . The American Journal of Clinical Nutrition . 97 . 4 . 689–97 . April 2013 . 23446891 . 3607650 . 10.3945/ajcn.112.051730 .
3. Pala V, Krogh V, Muti P, Chajès V, Riboli E, Micheli A, Saadatian M, Sieri S, Berrino F . Erythrocyte membrane fatty acids and subsequent breast cancer: a prospective Italian study . Journal of the National Cancer Institute . 93 . 14 . 1088–95 . July 2001 . 11459870 . 10.1093/jnci/93.14.1088 . free .
4. Sanchez-Bayle M, Gonzalez-Requejo A, Pelaez MJ, Morales MT, Asensio-Anton J, Anton-Pacheco E . A cross-sectional study of dietary habits and lipid profiles. The Rivas-Vaciamadrid study . European Journal of Pediatrics . 167 . 2 . 149–54 . February 2008 . 17333272 . 10.1007/s00431-007-0439-6 . 8798248 .
5. Dinu M, Pagliai G, Casini A, Sofi F . Mediterranean diet and multiple health outcomes: an umbrella review of meta-analyses of observational studies and randomised trials . European Journal of Clinical Nutrition . 72 . 1 . 30–43 . January 2018 . 28488692 . 10.1038/ejcn.2017.58 . 2158/1081996 . 7702206 . free .
6. Martinez-Lacoba R, Pardo-Garcia I, Amo-Saus E, Escribano-Sotos F . Mediterranean diet and health outcomes: a systematic meta-review . European Journal of Public Health . 28 . 5 . 955–961 . October 2018 . 29992229 . 10.1093/eurpub/cky113 . free .
7. Vessby B, Uusitupa M, Hermansen K, Riccardi G, Rivellese AA, Tapsell LC, Nälsén C, Berglund L, Louheranta A, Rasmussen BM, Calvert GD, Maffetone A, Pedersen E, Gustafsson IB, Storlien LH . Substituting dietary saturated for monounsaturated fat impairs insulin sensitivity in healthy men and women: The KANWU Study . Diabetologia . 44 . 3 . 312–9 . March 2001 . 11317662 . 10.1007/s001250051620 . free .
8. Lovejoy JC . The influence of dietary fat on insulin resistance . Current Diabetes Reports . 2 . 5 . 435–40 . October 2002 . 12643169 . 10.1007/s11892-002-0098-y . 31329463 .
9. Fukuchi S, Hamaguchi K, Seike M, Himeno K, Sakata T, Yoshimatsu H . Role of fatty acid composition in the development of metabolic disorders in sucrose-induced obese rats . Experimental Biology and Medicine . 229 . 6 . 486–93 . June 2004 . 15169967 . 10.1177/153537020422900606 . 20966659 .
10. Abdullah MM, Jew S, Jones PJ . Health benefits and evaluation of healthcare cost savings if oils rich in monounsaturated fatty acids were substituted for conventional dietary oils in the United States . Nutrition Reviews . 75 . 3 . 163–174 . February 2017 . 28158733 . 5914363 . 10.1093/nutrit/nuw062 .
11. Huth PJ, Fulgoni VL, Larson BT . A systematic review of high-oleic vegetable oil substitutions for other fats and oils on cardiovascular disease risk factors: implications for novel high-oleic soybean oils . Advances in Nutrition . 6 . 6 . 674–93 . November 2015 . 26567193 . 4642420 . 10.3945/an.115.008979 .
12. Book: Fat content and composition of animal products: proceedings of a symposium, Washington, D.C., December 12-13, 1974 . 1976 . National Academy of Sciences. Washington. 978-0-309-02440-2 . 25032409 . National Research Council (US) Board on Agriculture and Renewable Resources .
13. Aizpurua-Olaizola O, Ormazabal M, Vallejo A, Olivares M, Navarro P, Etxebarria N, Usobiaga A . Optimization of supercritical fluid consecutive extractions of fatty acids and polyphenols from Vitis vinifera grape wastes . Journal of Food Science . 80 . 1 . E101-7 . January 2015 . 25471637 . 10.1111/1750-3841.12715 .