Final answer:
Dietary patterns high in saturated fatty acids increase LDL cholesterol levels in the blood. Unsaturated fatty acids are beneficial as they help lower LDL and raise HDL cholesterol, promoting healthy blood cholesterol levels.
Step-by-step explanation:
Dietary patterns high in saturated fatty acids tend to increase the level of LDL in the blood. Saturated and trans fatty acids can act as catalysts for the increase of LDL cholesterol, which is often referred to as 'bad' cholesterol. On the other hand, polyunsaturated fatty acids, like omega-3 fatty acids, are beneficial as they can lower LDL and elevate HDL, known as 'good' cholesterol, contributing to healthy blood cholesterol levels.
It is important to understand that while some lipids are essential for our body, excess dietary lipids, especially those from saturated fatty acids and trans fats, might lead to health problems such as cardiovascular disease. Trans fats not only increase LDL levels but also decrease HDL levels, negatively impacting total blood cholesterol. Hence, replacing saturated fat with unsaturated fat in the diet, alongside a reduction in trans fatty acids, is recommended for lowering serum cholesterol and reducing the risk of heart disease.