Trans fatty acids linked to myocardial infarction and stroke: What is the evidence?

Consumption of industrially produced trans fatty acids (IP-TFAs) increases LDL cholesterol, either decreases or has no effect on HDL cholesterol, and increases markers of inflammation. Observational studies have shown that consumption of TFA produced by partial hydrogenation of vegetable oils (PHOs) is associated with increased mortality and incidence of MI and stroke rates. Regulatory initiatives to restrict PHOs to less than 2 g per day from food sources, along with concurrent initiatives to reduce tobacco exposure, have been associated with reduction in cardiovascular mortality and MI rates. What remains unknown is whether the consumption of amounts <2 g per day of PHOs is also harmful and whether TFAs present in milk and the meats of ruminant animals is beneficial or harmful.