Cholesterol: Good or bad for your health?

Donya Betancourt, Pediatrician, Sanur, Bali, drdonya@hotmail.com

People tend to think of it in negative ways but cholesterol is one of several types of fat that are necessary for good health.

Cholesterol is an important component of cell membranes and is vital to the structure and function of all your body's cells and it is also a component in many hormones.

But when the level of cholesterol and triglyceride (another blood fat) become too high, deposits of cholesterol in blood vessels increase and create plaques which narrow arteries, creating a condition called atherosclerosis. Narrowing of the arteries around your heart (coronary artery disease) means an increased risk of a heart attack.

Likewise, decreased blood flow to your brain can cause a stroke, and less blood flowing to your lower limbs may result in gangrene.

Cholesterol is one of two lipids that circulate in blood. Triglycerides are another form of fat that moves through your blood as transportable fuel used for energy. Since both of them are fats and are insoluble in water, they must be carried by proteins called apoproteins.

A lipoprotein is a combination of a lipid and an apoprotein. There are three main types of lipoprotein: LDL (low-density lipoprotein), HDL (high-density lipoprotein) and VLDL (very low- density lipoprotein).

The cholesterol carried in LDL particles is known as LDL cholesterol. LDL cholesterol is sometimes called bad cholesterol because it transports cholesterol to sites throughout your body, where it's either deposited or used to repair cell membranes. It is like hard water which causes lime to build up inside plumbing. LDL cholesterol promotes accumulation of cholesterol in the walls of your arteries.

The cholesterol carried in HDL particles is known as HDL cholesterol. HDL cholesterol helps clear excess cholesterol from your body and so is sometimes called good cholesterol.

Very-low-density lipoprotein (VLDL) contains mostly triglycerides and small amounts of protein and cholesterol.

Having a low level of LDL cholesterol and a high level of HDL cholesterol is desirable for lowering your risk of developing plaques and coronary artery disease. You may have high LDL cholesterol as a result of genetic makeup or lifestyle choices, or both. Your genes can give you cells that do not remove LDL cholesterol from your blood efficiently, or a liver that produces too much cholesterol as VLDL particles. Your genetic makeup also can result in too few HDL particles.

When screening for cholesterol, you should check not only for cholesterol but also HDL cholesterol and triglyceride.

Lifestyle choices that cause high cholesterol are inactivity, lack of exercise, obesity, smoking, high blood pressure, diabetes (type 2), family history and diet.

Cholesterol occurs in foods sourced from animals such as meat, eggs and cheese. "No cholesterol oils" are named such because they are made from plants or vegetable oils. Olive oil is the most suitable oil if you can afford to buy it but I think controlling your total fat intake such as eating less organ meat, egg yolks and whole milk products can limit cholesterol levels.

Consider foods high in soluble fiber, including oat bran, oatmeal, beans, peas, rice, bran, barley, citrus fruits, strawberries and apple pulp. Eat more fish, such as salmon, mackerel and herring and soy products which can produce good "HDL cholesterol" to help protect yourself against heart disease. And get more exercise.

If you drink, drink moderately, no more than two drinks a day. If you are a nondrinker, don't start drinking alcohol. Don't drink if you have a high triglyceride.

If you smoke, stop. If you don't, don't start. Cigarette smoking damages the walls of your blood vessels, making them prone to accumulate fatty deposits. If you stop smoking, your HDL cholesterol may return to its former level.