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.
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]
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 20th 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]
^Sanchez-Bayle M, Gonzalez-Requejo A, Pelaez MJ, Morales MT, Asensio-Anton J, Anton-Pacheco E (February 2008). "A cross-sectional study of dietary habits and lipid profiles. The Rivas-Vaciamadrid study". European Journal of Pediatrics. 167 (2): 149–54. doi:10.1007/s00431-007-0439-6. PMID17333272. S2CID8798248.
^Dinu M, Pagliai G, Casini A, Sofi F (January 2018). "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. doi:10.1038/ejcn.2017.58. hdl:2158/1081996. PMID28488692. S2CID7702206.
^
Fukuchi S, Hamaguchi K, Seike M, Himeno K, Sakata T, Yoshimatsu H (June 2004). "Role of fatty acid composition in the development of metabolic disorders in sucrose-induced obese rats". Experimental Biology and Medicine. 229 (6): 486–93. doi:10.1177/153537020422900606. PMID15169967. S2CID20966659.
^Aizpurua-Olaizola O, Ormazabal M, Vallejo A, Olivares M, Navarro P, Etxebarria N, Usobiaga A (January 2015). "Optimization of supercritical fluid consecutive extractions of fatty acids and polyphenols from Vitis vinifera grape wastes". Journal of Food Science. 80 (1): E101-7. doi:10.1111/1750-3841.12715. PMID25471637.
^"09038, Avocados, raw, California". National Nutrient Database for Standard Reference, Release 26. United States Department of Agriculture, Agricultural Research Service. Archived from the original on January 10, 2014. Retrieved 14 August 2014.