Cholesterol and heart disease

Cholesterol is a fat-like substance, found in the blood stream and also in bodily organs and nerve fibres. Cholesterol is needed in the body to insulate nerves, make cell membranes and produce certain hormones, and it is an important lipid in some membranes.

Cholesterol can be both good and bad. High-density lipoprotein (HDL) is good cholesterol and low-density lipoprotein (LDL) is bad cholesterol.

*High density lipoprotein, or HDL, which also is called the “good” cholesterol because it takes cholesterol from tissues to the liver, which removes it from the body.

*Low density lipoprotein, or LDL, which also is called the “bad” cholesterol because it carries cholesterol to tissues, including the arteries. It can build up in the arteries and form fatty, waxy deposits called plaques. It will increase the risk of getting heart disease.

Excess cholesterol in the bloodstream can form plaque (a thick, hard deposit) in artery walls. The cholesterol or plaque build-up causes arteries to become thicker, harder and less flexible, slowing down and sometimes blocking blood flow to the heart.

High LDL cholesterol can damage the arteries and increase the risk of heart attacks (myocardial infarction - MI), chest pain (angina), narrowing of the blood vessels (peripheral artery disease) and stroke – as a group these are called cardio vascular disease (CVD).

High cholesterol levels in blood are mainly caused by eating foods high in saturated fats and trans-fats, and not including foods with unsaturated fats and with fibre.

Saturated fat and cholesterol in the food can make blood cholesterol level go up. Saturated fat is the main culprit, but cholesterol in foods also matters. Reducing the amount of saturated fat and cholesterol in the diet helps lower blood cholesterol level.

Example of foods containing saturated fats and trans-fats –such as fatty meats, full-fat dairy products, butter, coconut oil, palm oil and most deep-fried takeaway foods and commercially baked products, such as pies, biscuits, buns and pastries. Food high in trans-fats include most commercially baked products and deep-fried takeaway foods.

Cholesterol lowering is important for everyone–younger, middle age, and older adults; women and men; and people with or without heart disease.
Cholesterol and heart disease

Low-density lipoprotein (LDL) cholesterol

Cholesterol and triglycerides are fats and are insoluble in the blood. However, when they combine with protein they became lipoproteins and are able to dissolve in and be carried by blood throughout body.

Low density lipoprotein (LDL) is cholesterol packaged in a protein and phospholipid coat. Cholesterol is insoluble, so it must be encased in this coat to facilitate transport in the blood.

 

LDL is the major cholesterol carrier to the periphery and supplies the cholesterol essential for the integrity of nerve tissue, steroid hormone synthesis, and cell membranes. It circulates throughout the body and is available to all cells.

As LDL circulates in the blood it may adhered to arterial walls which feed the heart and brain. When there is too much LDL cholesterol circulating in the blood, it can slowly build up in the walls of the arteries that feed the heart and brain. It forms plaque and may result in a blockage in the artery which may lead to arthrosclerosis.

The association between elevated plasma cholesterol carried in LDL and the risk of coronary heart disease has been well established. LDL is also sometimes called the ‘bad’ cholesterol.
Low-density lipoprotein (LDL) cholesterol