The four common unsaturated fatty acid are monoenoic acid, (oleic acid) dienoic acid (linoleic acid) and trienoic (linolenic acid) and tetraenoic acid (arachidonic acid). Out of them oleic acid can be synthesised by human body rest three essential fatty acid must be present in diet. Edible oil having essential fatty acid are sunflower and safflower, coconut cotton seed, sesame, rape seed oil, mustard and groundnut oil. However, sunflower and safflower oil possess the highest content of essential fatty acids.