: Cholesterol is a fatty substance that is an important part of the outer lining of cells in the body of animals. Cholesterol is also found in the blood circulation of humans. Cholesterol in the blood originates from dietary intake and liver production. Dietary cholesterol comes primarily from animal sources including meat, poultry, fish, and dairy products.
LDL (low density lipoprotein) cholesterol is called "bad" cholesterol because elevated levels of LDL cholesterol are associated with an increased risk of heart disease.
HDL (high density lipoprotein) cholesterol is called the "good" cholesterol because HDL cholesterol particles prevent atherosclerosis by extracting cholesterol from artery walls and disposing of them through liver metabolism. High levels of LDL cholesterol and low levels of HDL cholesterol are risk factors for atherosclerosis.
Atherosclerosis - a degenerative disease of the arteries characterized by patchy thickening of the inner lining of the arterial walls, caused by deposits of fatty material.
What causes high cholesterol? There are many factors that can increase your chance of having heart problems or stroke if you have high cholesterol, including the following: An unhealthy diet: some foods already contain cholesterol (known as dietary cholesterol) but it is the amount of saturated fat in your diet which is more important; Smoking: a chemical found in cigarettes called acrolein stops HDL transporting fatty deposits to the liver, leading to narrowing of the arteries (atherosclerosis): Having diabetes or high blood pressure (hypertension); Having a family history of stroke or heart disease.
The amount of cholesterol in the blood (both LDL and HDL) can be measured with a blood test. The recommended cholesterol levels in the blood vary between those with a higher or lower risk of developing arterial disease.
There is also an inherited condition known as familial hypercholesterolaemia (FH). This can cause high cholesterol even in someone who eats healthily.
How can I lower my cholesterol levels? The first step in reducing cholesterol is to maintain a healthy, balanced diet. It is important to keep your diet low in fatty food. Try to swap food containing saturated fat for fruit, vegetables and wholegrain cereals. This will also help to prevent high cholesterol from returning. Other lifestyle changes can also make a big difference. It will help to lower your cholesterol if you do regular exercise and quit smoking.