What happens when olive oil is hardened?

When olive oil is hardened, it undergoes a process called hydrogenation, where hydrogen is added to the oil, converting some of its unsaturated fats into saturated fats. This results in a thicker, more solid consistency, often used in products like margarine or shortening. However, hydrogenation can lead to the formation of trans fats, which are linked to various health issues. The flavor and nutritional profile of the olive oil may also change, becoming less beneficial compared to its liquid form.