Nowadays, cholesterol has become a major health issue. People start to realize that many serious diseases, such as heart disease, atherosclerosis and stroke are related to it. But there are also myths about cholesterol that should not be taken for granted. The best way to avoid misleading information is to equip ourselves with basic knowledge of cholesterol. We may start by proposing some questions: What is cholesterol? Does it always bring negative impact to our body? What are the sources of cholesterol? What causes high cholesterol?
Cholesterol is a chemical compound that is naturally produced by the body (predominantly in the liver) and is structurally a combination of lipid (fat) and steroid. It also comes from dietary intake, primarily from animal sources, like dairy products, eggs, and meat. Cholesterol exists in the outer layer of every cell in our body and has many functions. The body needs cholesterol to function properly. It is required to establish proper membrane permeability and fluidity, produce hormones, vitamin D, and the bile acids. But when it comes in excessive amount, serious health problems may develop.
Bad and Good Cholesterol
To understand the good and bad side of cholesterol, we need to know that there are several types of cholesterol. Cholesterol travels through the blood attached to a protein — this cholesterol-protein package is called a lipoprotein.
- Low density lipoproteins (LDL). LDL is known as “bad” cholesterol. It can cause buildup of plaque on the walls of arteries. This type of cholesterol is associated with the increased risk of heart disease.
- High density lipoproteins (HDL). HDL, also known as “good” cholesterol, can prevent atherosclerosis by extracting cholesterol from artery walls and disposing of them through liver metabolism. Thus, high levels of HDL can be seen as a good indicator of a healthy heart.
- Very low density lipoproteins (VLDL). VLDL is similar to LDL cholesterol in that it contains mostly fat and not much protein. It is also associated with atherosclerosis and heart disease.
- Triglycerides. Triglycerides are another type of fat that is carried in the blood by very low density lipoproteins. Excess calories, alcohol, or sugar in the body are converted into triglycerides and stored in fat cells throughout the body.