Malondialdehyde (MDA) and conjugated dienes (CD) in the liver of rats fed with high fat diet with different trans fatty acid levels. C: controls group, FSO: Fresh soybean oil fed group, OSO: oxidized soybean oil-fed group, MG: margarine-fed group. Data are expressed as means ± SD (n = 12 rats per group). Comparison between groups was made using Duncan's test. Values followed by different subscript letters are significantly different. (p < 0.05).