Why did consumption of trans fats rise after concerns about saturated fat grew?

In the late 1980s, the consumption of trans fat increased significantly because it was used as a replacement for products containing saturated fat, such as lard and tallow.1

This shift occurred after an association between high intake of saturated fat and an increased risk of heart disease was firmly established. At that time, trans-fat-based products were favored because they offered similar functional properties, such as smoke points, and were widely perceived to be a healthier alternative to saturated fats.1

It is important to note that this transition was based on a misunderstanding of health risks; subsequent evidence in the 1990s revealed that trans fats actually carry a higher risk for heart disease than saturated fats. Trans fats are now known to negatively impact cardiovascular health by increasing "bad" (LDL) cholesterol while simultaneously lowering "good" (HDL) cholesterol.12