Oleic acid coronary heart disease

Monounsaturated fats Triacylglycerols containing primarily fatty acids with one double bond are referred to as monounsaturated fat. Unsaturated fatty acids are generally derived from vegetables and fish. When substituted for saturated fatty acids in the diet, monounsaturated fats lower both total plasma cholesterol and LDL cholesterol, but increase HDLs. This ability of monounsaturated fats to favorably modify lipoprotein levels may explain, in part, the observation that Mediterranean cultures, with diets rich in olive oil (high in monounsaturated oleic acid), show a low incidence of coronary heart disease. 

The typical sunflower oil composition is 66-72% linoleic acid, 12% saturated acids (palmitic and stearic), 16-20% oleic acid, and less than 1% a-linolenic acid. An increase in low-density lipoprotein cholesterol (LDL-C) and a decrease of high-density lipoprotein cholesterol (HDL-C) are believed risk factors of coronary heart disease (CHD). Diets rich in saturated fat increase plasma total and LDL-C. Traditional high-linoleic sunflower oil has always been regarded as healthy because of its high content of polyunsaturated fatty acids (PUFA) and relatively low content in saturated fatty acids. 

Elevated use of extra-virgin olive oils, which are particularly rich in these phenolic antioxidants, as well as squalene, oleic and other unsaturated acids, should afford significant protection against cancer (colon, skin, breast), coronary heart disease and ageing by inhibiting oxidative stress [44],... 

The negative effect attributed to lauric and myristic acid explains why foods rich in SFA should be consumed in moderation and there is convincing evidence that PA increases the risk of cardiovascular disease (World Health Organization, 2003). Palm oil raises plasma cholesterol only when the diet contains excess dietary cholesterol, in whieh case the risk of coronary heart disease may rise (Jones, 1989). Temme et al. (1996) reported that both PA and lauric acid are hypercholesterolaemic compared with oleic acid. 

The nutritional value of nut and seed products is closely associated with the fatty acid content of the oil. High Unoleic acid content decreases shelf-life. Increasing the oleic/linoleic acid ratio produces a more stable oil with a longer shelf-life. Nutritionally, a high linoleic acid content is desirable, because this acid is an essential fatty acid and produces a hypocholenic effect. Of more than 100 fatty acids, three are essential, linoleic, linolenic and arachidonic. The consensus is that polyunsaturated fat (fatty acids) lowers total blood cholesterol and low-density lipoprotein levels. Lx)w levels of these substances are associated with reduced risk of coronary heart disease and atherogenesis. Mono-unsaturated fatty acids may be beneficial in lower blood cholesterol (Sheppard and Rudolf, 1991). 

A number of PUFA are essential micronutrients or have been ascribed particular health benefits, including oleic acid, linoleic acid, y-linolenic acid (GLA), EPA and DHA [see Chapters 8, 9 and 10]. There is strong and well-documented evidence that n-3 (commonly referred to as omega-3) long-chain PUFA such as EPA and DHA can lower the risk of coronary heart disease. There is also growing evidence that they can have beneficial effects related to inflammatory diseases, early development, neurological diseases and cognitive performance. 

In the United States, the Food and Drug Administration (FDA, 2006) has approved a health claim for conventional canola oil that states canola is high in unsaturated fats and consnming 1.5 tablespoons of canola oil per day may reduce the risk of coronary heart disease . Potential health benefits of conventional canola oil are largely due to its relatively low levels of saturated fatty acids (SFA 1% of total fatty acids) and high amonnts of the monounsaturated fatty acid (MUFA), oleic acid (OA 61% of total fatty acids Canola Council of Canada, 2008). Conventional canola oil is also a good source of two essential polyunsaturated fatty acids (PUFA), linoleic acid (LA 21% of total fatty acids), an n-6 PUFA, and alpha-linolenic acid (ALA 11% of total fatty acids), an n-3 PUFA. This composition of LA and ALA results in a low, 2 1 ratio of n-6 n-3. 

---