What Is Cholesterol?
Cholesterol is a type of chemical known as a sterol. It is a waxy substance that forms part of the membranes that surround every cell and helps to determine which substances can pass in and out of the cells. It is an essential component of the body that is also used to produce certain hormones, vitamin D and the bile acids that help to digest fats.
Cholesterol is produced by animals, usually in their liver and it is the most common steroid in the body. Approximately three quarters of the cholesterol that is present in the body has been created by the body itself. The rest is usually obtained from food. Cholesterol is only produced by animals. Plants do not make cholesterol, so fruits and vegetables do not contain any cholesterol.
Cholesterol is transported in the blood. In order to be dissolved in the blood, cholesterol must be attached to a carrier lipoprotein. Two types of carriers can move cholesterol through the blood, LDL and HDL.
The levels of cholesterol in the body can sometimes rise too high, particularly if a lot of saturated fats are being eaten since these types of fats can be converted into cholesterol. When this happens, the amount of cholesterol in the blood becomes too large. The bad cholesterol, which is the cholesterol attached to LDL, can form deposits inside the blood vessels. These deposits can be dangerous. They harden and narrow the arteries, and they can break away from the wall of the blood vessel and be carried through the circulatory system, potentially forming clots or blockages elsewhere in the body. The obstructions created by bad cholesterol can cause heart attacks and strokes.
Good cholesterol, which is the cholesterol that is being carried by HDL, does not form deposits or plaques inside the blood vessels. The proportion of cholesterol in the blood that is being carried by HDL rather than LDL is usually about one quarter or one third. The greater the amount of good cholesterol compared to the amount of bad cholesterol, the better. The proportion of good cholesterol in the blood can be increased through regular physical exercise and the consumption of a healthy diet that is low in saturated fats.
Cholesterol is not in itself a dangerous or unhealthy substance. Without it, the body would fail to function. It is the amount of cholesterol in the body, rather than its presence that poses a health risk. When there is too much cholesterol in the blood, it begins to form plaques within the blood vessels, which can lead to cardiovascular problems.