Good vs. bad cholesterol

Cholesterol is a fatty substance that your body produces naturally, and it’s essential for a number of functions. For example, we need cholesterol to produce new cell membranes.

Despite this, we are all told that we need to watch our dietary cholesterol intake and avoid the negative impacts of high blood cholesterol levels (hypercholesterolemia). Consuming too much cholesterol in your diet can increase your risk of high blood pressure, heart disease, stroke and cancer.

So, cholesterol can be both good and bad, and this depends mostly on what kind of cholesterol you’re talking about.

Types of cholesterol

There are two kinds of cholesterol - low-density lipoproteins (LDLs) and high-density lipoproteins (HDLs). The latter is the good kind, and the former is known as the bad kind of cholesterol.

LDLs are ‘bad’ because they contain more cholesterol than protein, and they deposit in the artery walls, narrowing them and increasing your blood pressure. In turn, this increases your risk of atherosclerosis or arteriosclerosis and coronary artery disease (CHD).

HDLs are ‘good’ because they contain more protein than cholesterol, and they actually help to remove deposited LDLs from the artery walls. They transfer these LDLs to the liver, where they can be broken down and excreted. Therefore, HDL lower your risk of atherosclerosis or arteriosclerosis and CHD.

Causes of high blood cholesterol

High blood cholesterol is caused mostly by a poor diet and a sedentary lifestyle. Your risk of this condition is also increased by alcohol consumption, smoking, and certain chronic medical conditions like type 2 diabetes and metabolic syndrome.

How is cholesterol measured?

Cholesterol is measured using a blood test. Depending on what country you live in, your results will be reported in mmol/L (millimoles per litre) or mg/dL (milligrams per decilitre).