Dietary Lipids and Health

Yong Li Purdue University, West Lafayette, Indiana, Dietary Lipids and Health. 

We still do not have a complete understanding of the relationship between dietary lipids and health. A moderate amount of fat is needed in everyone s diet, but many people consume much more than required. Research results indicate a correlation between the consumption of too mnch fat, and fat of the wrong type (satnrated fatty acids), and two of the greatest health problems obesity and cardiovascnlar disease. Because of these results, there is a recommended reduction in the percentage of calories obtained from fats— from the national average of almost 42% to no more than 30%. 

This chapter introduces the contemporary understanding of food lipids in nutrition and health. The health aspects of dietary lipids and the underlying cellular and molecular mechanisms of PUFA actions are also discussed. A primary focus is placed on the role of dietary fat in cardiovascular disease and atherosclerosis. 

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Geleijnse et al., 2002 Mukamal et al., 2002], Mechanisms by which these compounds exert their cardiovascular protective effects are still unknown. It is widely hypothesized that dietary flavonoids improve cardiovascular health and may help to prevent cardiovascular diseases/events by inhibiting pathogenic processes such as oxidative stress (lipid and protein peroxidation), inflammation, endothelial dysfunction, and platelet activation [Nijveldt et al., 2001]. 

To advance understanding of the dynamic influence of dietary lipids, research efforts are focusing on the importance of the balance between n-6 and n-3 fatty acids in the human diet. What is emerging is recognition that these PUFAs modulate eicosanoid biosynthesis in numerous tissues and cell types, alter signal transduction, and influence gene expression (87, 118). The effect of n-6 and n-3 PUFA on CVD, cancer and bone/joint health is related to the newer discoveries of how dietary PUFA impact health. 

The compositional characteristics of almond oil show that it is rich in several health-promoting nutrients, many of which may be responsible for the observed benehcial effects of dietary almond consumption in cardiovascular diseases (11) and in weight management (12), however, few investigations have explored this topic. Hyson et al. (13) conducted a dietary intervention study to determine whether the consumption of whole almonds or almond oil for 6 weeks would result in similar or different effects on plasma lipids and ex vivo LDL oxidation. Both groups consumed diets with identical almond oil and total fat levels. This study showed that both whole almond and almond oil consumption caused similar reductions in plasma cholesterol and LDL (4% and 6%, respectively) as well as a 14%... 

Truswell, A.S. and Beynen, A.C. 1992. Dietary fiber and plasma lipids potential for prevention and treatment of hyperlipidaemias, in Dietary Fiber—A Component of Food, Nutritional Function in Health and Disease, eds., T.F. Schweizer and C.A. Edwards, New York Springer-Verlag, pp. 295-332. 

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