In recent years, a newer health diet paradigm which in the use of further emphasized the positive aspects of diet. Polyunsaturated fatty acid (PUFA) is one, which is considered to possess various nutraceutical properties, determined through epidemiologic and clinical studies, omega 3 PUFAs at a higher inclusion levels in our diet can guard us against inflammatory diseases, cancer therapy, cardiovascular symptoms, bipolar disorder, kidney disease, attention deficit disorder with hyperactivity in children, growth, and development in fetal and infant feeding and immune responses. Whereas the diets enriched in omega-6 PUFAs are associated with inflammation, in development of the brain, coronary heart disease, and rheumatoid arthritis. In this chapter, a detailed description of PUFA such as omega-3 and omega-6 FAs metabolism, their nutraceutical role and the importance of conjugated linoleic acid in CVD and cancer has been discussed extensively. The review also states that the significance of PUFA (omega-3 and omega-6) balances is to be consumed in the regular diet.