Monounsaturated fat: Difference between revisions
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== Relation to health == |
== Relation to health == |
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Olive oil is a key component of the [[Mediterranean diet]], widely regarded as being protective against [[cardiovascular disease]], while [[Tea-oil Camellia]] has been a traditional part of Asian food. Although polyunsaturated fats protect against cardiovascular disease by providing more [[biological membrane|membrane]] fluidity than monounsaturated fats, they are more vulnerable to [[lipid peroxidation]] ([[rancidification|rancidity]]). On the other hand, some monounsaturated fatty acids (like saturated fats) promote [[insulin resistance]], whereas polyunsaturated fatty acids are protective against insulin resistance <ref>{{cite journal| author=Lovejoy, JC| title=The influence of dietary fat on insulin resistance| journal=Current Diabetes Reports| year=2002| volume=2| issue=5| pages= 435–440| |
Olive oil is a key component of the [[Mediterranean diet]], widely regarded as being protective against [[cardiovascular disease]], while [[Tea-oil Camellia]] has been a traditional part of Asian food. Although polyunsaturated fats protect against cardiovascular disease by providing more [[biological membrane|membrane]] fluidity than monounsaturated fats, they are more vulnerable to [[lipid peroxidation]] ([[rancidification|rancidity]]). On the other hand, some monounsaturated fatty acids (like saturated fats) promote [[insulin resistance]], whereas polyunsaturated fatty acids are protective against insulin resistance <ref>{{cite journal| author=Lovejoy, JC| title=The influence of dietary fat on insulin resistance| journal=Current Diabetes Reports| year=2002| volume=2| issue=5| pages= 435–440| pmid=12643169| doi=10.1007/s11892-002-0098-y}}</ref><ref>{{cite journal| author=Satoshi Fukuchi| title=Role of Fatty Acid Composition in the Development of Metabolic Disorders in Sucrose-Induced Obese Rats| journal=Experimental Biology and Medicine| year=2004| volume=229| issue=6| pages= 486–493| url=http://www.ebmonline.org/cgi/content/full/229/6/486| pmid=15169967}}</ref>. In direct contrast to this, the large scale KANWU study found that neither dietary monounsaturated or supplemented polyunsaturated fats (in the form of fish oil) affected insulin sensitivity, while increased consumption of saturated fat induced a significant decrease in this parameter. <ref>{{cite journal| author=Vessby B, Unsitupa 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| title=Substituting dietary saturated for monounsaturated fat impairs insulin sensitivity in healthy men and women: The KANWU Study.| journal=Diabetologia| year=2001| volume=44| issue=3| pages= 312–319| url=http://www.ncbi.nlm.nih.gov/pubmed/11317662?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_Discovery_RA&linkpos=2| pmid=11317662| doi=10.1007/s001250051620}}</ref> |
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Foods containing monounsaturated fats lower [[LDL]] cholesterol, while possibly raising [[High density lipoprotein|HDL]] cholesterol.<ref>''You Can Control Your Cholesterol: A Guide to Low-Cholesterol Living'' by [[Merck & Co.]] Inc.</ref> However, their true ability to raise HDL is still in debate. |
Foods containing monounsaturated fats lower [[LDL]] cholesterol, while possibly raising [[High density lipoprotein|HDL]] cholesterol.<ref>''You Can Control Your Cholesterol: A Guide to Low-Cholesterol Living'' by [[Merck & Co.]] Inc.</ref> However, their true ability to raise HDL is still in debate. |
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Revision as of 21:53, 3 May 2008
| Types of fats in food |
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| Components |
| Manufactured fats |
- For discussion how dietary fats affect cardiovascular health, see Diet and heart disease.
In biochemistry and nutrition, monounsaturated fats are fatty acids that have a single double bond in the fatty acid chain and all the carbon atoms in the chain are single-bonded. By contrast, polyunsaturated fatty acids have more than one double bond.
Fatty acids are long-chained molecules having a methyl group at one end and a carboxylic acid group at the other end. Fatty acid fluidity increases with increasing number of double bonds. Therefore, monounsaturated fatty acids have a higher melting temperature than polyunsaturated fatty acids but lower than saturated fatty acids. Monounsaturated fatty acids are liquids at room temperature and semisolid or solid when refrigerated.
Molecular description: oleic acid
Common monounsaturated fatty acids are palmitoleic acid (16:1 n−7), cis-vaccenic acid (18:1 n−7) and oleic acid (18:1 n−9). Palmitoleic acid has 16 carbon atoms with the first double bond occurring 7 carbon atoms away from the methyl group (and 9 carbons from the carboxyl end). It can be lengthened to the 18-carbon cis-vaccenic acid. Oleic acid has 18 carbon atoms with the first double bond occurring 9 carbon atoms away from the methyl group. The illustrations below show a molecule of oleic acid in skeletal formula and as a space-filling model.
Relation to health
Olive oil is a key component of the Mediterranean diet, widely regarded as being protective against cardiovascular disease, while Tea-oil Camellia has been a traditional part of Asian food. Although polyunsaturated fats protect against cardiovascular disease by providing more membrane fluidity than monounsaturated fats, they are more vulnerable to lipid peroxidation (rancidity). On the other hand, some monounsaturated fatty acids (like saturated fats) promote insulin resistance, whereas polyunsaturated fatty acids are protective against insulin resistance [1][2]. In direct contrast to this, the large scale KANWU study found that neither dietary monounsaturated or supplemented polyunsaturated fats (in the form of fish oil) affected insulin sensitivity, while increased consumption of saturated fat induced a significant decrease in this parameter. [3]
Foods containing monounsaturated fats lower LDL cholesterol, while possibly raising HDL cholesterol.[4] However, their true ability to raise HDL is still in debate.
In a study published in 2001, erythrocyte membrane oleic and monounsaturated fatty acid content was positively associated with breast cancer risk in postmenopausal women, while no association was shown between saturated fatty acids and breast cancer risk. Enzyme Δ9-desaturase catalyzes the conversion of stearic acid to oleic acid: there is a negative correlation between erythrocyte membrane oleic acid and dietary polyunsaturated fatty acids. Inverse relationship between Saturation Index (ratio of membrane stearic to oleic acid) and breast cancer risk could also be related to hormonal and metabolic factors and to interactions between them, as well as to dietary factors.[5]
In children, consumption of monounsaturated oils is associated with healthier serum lipid profiles.[6]
Natural sources
Monounsaturated fats are found in natural foods such as nuts and avocados, and are the main component of tea seed oil and olive oil (oleic acid). Canola oil is 57%–60% monounsaturated fat, olive oil is about 75% monounsaturated fat while tea seed oil is commonly over 80% monounsaturated fat. Other sources include grapeseed oil, ground nut oil, peanut oil, flaxseed oil, sesame oil, corn oil, popcorn, whole grain wheat, cereal, oatmeal, safflower oil, sunflower oil, tea-oil Camellia.
References
- ^ Lovejoy, JC (2002). "The influence of dietary fat on insulin resistance". Current Diabetes Reports. 2 (5): 435–440. doi:10.1007/s11892-002-0098-y. PMID 12643169.
- ^ Satoshi Fukuchi (2004). "Role of Fatty Acid Composition in the Development of Metabolic Disorders in Sucrose-Induced Obese Rats". Experimental Biology and Medicine. 229 (6): 486–493. PMID 15169967.
- ^ Vessby B, Unsitupa 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 (2001). "Substituting dietary saturated for monounsaturated fat impairs insulin sensitivity in healthy men and women: The KANWU Study". Diabetologia. 44 (3): 312–319. doi:10.1007/s001250051620. PMID 11317662.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ You Can Control Your Cholesterol: A Guide to Low-Cholesterol Living by Merck & Co. Inc.
- ^ Valeria Pala, Vittorio Krogh, Paola Muti, Véronique Chajès, Elio Riboli, Andrea Micheli, Mitra Saadatian, Sabina Sieri, Franco Berrino (2001). "Erythrocyte Membrane Fatty Acids and Subsequent Breast Cancer: a Prospective Italian Study". JNCL. 93. Retrieved 2008-03-22.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Sanchez-Bayle M, Gonzalez-Requejo A, Pelaez MJ, Morales MT, Asensio-Anton J, Anton-Pacheco E (2008). "A cross-sectional study of dietary habits and lipid profiles. The Rivas-Vaciamadrid study". Eur. J. Pediatr. 167 (2): 149–54. doi:10.1007/s00431-007-0439-6. PMID 17333272.
{{cite journal}}: CS1 maint: multiple names: authors list (link)
See also
External links
- Fats (Mayo Clinic)
- Types of Fats (Cardiovascular Consultants) Some "dated" information.
- The Chemistry of Unsaturated Fats