Cholesterol is lipophilic meaning it dissolves well in fat.
Dr Lee explained: “Cholesterol cannot circulate loosely in the blood, so your liver turns them into little parcels called lipoproteins and triglycerides to transport it around the body.”
There are good lipoproteins (high-density lipoproteins or HDL) there are bad lipoproteins (Low-density lipoproteins or LDL).
HDL carries cholesterol away from the heart and the arteries to be cleared in the liver, whereas LDL carries cholesterol to your heart and arteries, where fatty plaques can then develop.
Dr Lee said: “These then block the flow of blood to the tissue distal to the blockage. A raised LDL cholesterol is generally bad, whereas a raised HDL is general good.”
Raised cholesterol (LDL) is a risk factor for cardiovascular disease (heart attacks and strokes).
Dr Lee added: “Raised blood pressure is another risk factor, and in fact, the two are often found together, although this is not always the case.
“When cholesterol levels are too high, fatty plaques – known as atherosclerosis – are deposited in the artery walls.
“As a result, the artery wall becomes stiffer and less able to cope with the pressure of the blood flowing through them.
“This means that when cholesterol is raised, blood pressure is often raised too.
“High blood pressure is also more likely to cause damage to your arterial walls, causing small micro-tears.
“Atherosclerotic deposits then build up in these damaged sites, weakening the arterial wall.
“If the wall is damaged, the plaques can rupture, or the arterial wall can rupture, causing a major event such as a heart attack, a stroke, or a ruptured aneurysm.”