What is referred to as "bad cholesterol" due to its association with heart disease?

Low-density lipoproteins (LDL) are commonly referred to as "bad cholesterol" because elevated levels of LDL in the bloodstream are associated with an increased risk of heart disease. LDL carries cholesterol from the liver to the cells, and when there is an excess of it, it can lead to the buildup of plaque in the arteries, a condition known as atherosclerosis. This buildup can narrow the arteries and ultimately restrict blood flow, which can result in heart attacks or strokes.

In contrast, high-density lipoproteins (HDL) are often labeled as "good cholesterol" because they help remove cholesterol from the bloodstream and transport it back to the liver for excretion or recycling. This protective role of HDL contrasts sharply with the harmful effects attributed to high levels of LDL.

While saturated and trans fats can contribute to higher levels of LDL cholesterol when consumed in excess, they are not classified as "bad cholesterol" themselves. Instead, they are types of dietary fats that influence cholesterol levels. The distinction lies in the effects these substances have on heart health and cholesterol metabolism.