Dietary trans double bond containing fatty acids have been associated with increased risk of cardiovascular disease. There are two main sources of dietary trans fatty acids: meat and dairy fats, and partially hydrogenated fats. Because of a number of factors, including changes in federal labeling requirements for packaged foods, and local bans and grassroots pressure on the use of partially hydrogenated fat, trans fat intake has declined in recent years. Similar to saturated fatty acids, trans fatty acids increase plasma low density lipoprotein (LDL)-cholesterol concentrations. In contrast to saturated fatty acids, trans fatty acids do not increase high density lipoprotein (HDL)-cholesterol concentrations. These differences have been attributed to lipoprotein catabolic rate rather than production rate. When reported, effects of partially hydrogenated fat on glucose homeostasis, C-reactive protein, blood pressure, and LDL oxidation are modest. Although at this time some issues remain unresolved regarding trans fatty acids and CVD risk factors other than plasma lipoprotein concentrations, they should not affect the final dietary recommendation to limit intake.