Cholesterol is a soft, waxy substance found among the lipids (fats) in the bloodstream and in all your body's cells. It's an important part of a healthy body, it's used to form cell membranes, some hormones and is needed for other functions. But a high level of cholesterol in the blood  hypercholesterolemia is a major risk factor for coronary heart disease, which leads to heart attack.

 Types of  Cholesterol

Cholesterol is carried in the blood by molecules called lipoproteins. There are several different lipoproteins, but the three main types are:

Low density lipoprotein (LDL). This is often known as bad cholesterol and is thought to promote arterial disease. It carries cholesterol from the liver to the cells and can cause a harmful build-up if there is too much for the cells to use. Normally, the blood contains about 70% of LDL, but the level will vary from person to person

High density lipoprotein (HDL). This is often referred to as good cholesterol, and is thought to prevent arterial disease. It takes cholesterol away from the cells and back to the liver, where it is either broken down, or is passed from the body as a waste product.

Triglycerides are another type of fatty substance present in the blood. They are found in dairy products, meat and cooking oils. Triglycerides are also produced by the liver.

Those who are overweight, have a diet that is high in fatty or sugary foods, or drink a large amount of alcohol, have an increased risk of having a high triglyceride level.

 What Cause Cholesterol?