Cholesterol not only helps the body to build new cells, but it insulates nerves and helps in the production of hormones. Normally, our liver makes all the cholesterol that our body needs. But cholesterol also enters our body through food, such as fatty animal-based foods like milk, eggs, red meat and junk food with high trans fat and saturated fats.

High cholesterol levels in the body put the heart at risk, and that is why it is very important to maintain normal cholesterol levels.

There are three forms of cholesterol in our body:

Low-density lipoprotein (LDL) or the bad cholesterol,
High-density lipoprotein (HDL) or the good cholesterol, and
Triglycerides which are the type of cholesterol, which is stored in the body as fats.
A person having high cholesterol has high levels of LDL and triglycerides with low levels of HDL.

The normal cholesterol levels are:

HDL: Higher than 55 mg/dL for females and 45 mg/dL for males
LDL: Lower than 130 mg/dL, if you do not have heart disease or diabetes and not more than 100 mg/dL if you have heart disease or diabetes.
Triglycerides: Less than 150 mg/dL
High LDL cholesterol levels in the blood build up in the walls of your arteries and this cause a process called atherosclerosis. This leads to arteries become narrowed, and blood flow to the heart muscle is gradually slowed down or blocked.

A higher level of HDL is required to mop up these stray fats and take it back to the liver. Normal cholesterol levels with high HDL is achieved through physical activity and intake of omega-3 fatty acids.

As blood carries oxygen to the heart, blockages in your arteries can disrupt the flow of oxygen, thereby causing ischemic pain. If the blood is unable to reach even a portion of the heart due to a blockage, the person suffers from a heart attack.

Angioplasty opens up the arteries, which are blocked by fats and medicines are given to attain normal cholesterol levels.