Cholesterol explained

When you hear the word ‘cholesterol’, you’d be forgiven for thinking it’s an evil substance. After all, so much attention is paid to our cholesterol levels. But did you know we actually need cholesterol to keep our body working properly?

What is cholesterol?

Cholesterol is a fatty substance produced in the liver. It circulates around the body via the bloodstream and is responsible for many of our body’s metabolic processes, like producing hormones, Vitamin D, and bile acids. Around 75 per cent of our cholesterol is made in the liver. The rest comes from our diet.

The different types of cholesterol

Bupa Dietitian Rosalyn D’Angelo says our total cholesterol is a reading that includes two types of cholesterol: low-density lipoprotein (LDL) and high-density lipoprotein (HDL).
 
“LDL is the ‘bad’ cholesterol. Remember ‘L’ for lousy. We want these levels to be low, as LDL is the main cause of fatty build up in the arteries,” she explains.
 
“HDL is the ‘good’ cholesterol. Think ‘H’ for healthy. We want these levels to be high, as HDL has a protective effect on our heart, because it sweeps excess cholesterol out of the bloodstream.”

Knowing our cholesterol levels

Knowing your cholesterol level is important in managing your health. Even though we need it for our body to function properly, too much cholesterol is a health risk.
 
“If you have too much cholesterol circulating around in the blood, over time it builds up on the inside of your arteries as fatty deposits,” D’Angelo says. “Your arteries are like hoses that connect to your heart. When your arteries become narrowed, blood flow to the heart or brain is slowed down or blocked. A heart attack is when the blood flow to your heart is stopped. If this blockage happens in the carotid artery (the artery up your neck that leads to your brain), this can cause a stroke.”
Burger and fries

How is cholesterol measured?

Cholesterol levels are checked with a simple blood test and are measured in millimoles per litre of blood (mmol/L). But, when discussing cholesterol, most people drop off the ‘mmol/L’ and use the number instead (i.e. 5.8mmol/L is expressed as 5.8).
 
As well as measuring your LDL and HDL levels, a cholesterol test will also measure your triglycerides — another type of fat in your blood that can raise the risk of heart disease. Your non-high density lipoprotein (NHDL-C) may also be included, which is your total cholesterol minus your HDL cholesterol.

What if your levels are high?

If your levels are high, your doctor will advise the best course of action. Strategies to improve your cholesterol levels may include:

  • changing your diet
  • increasing your physical activity
  • taking prescription medication
  • reducing your alcohol consumption
  • making other lifestyle changes.

How often should cholesterol levels be checked?

It is generally recommended that everyone over 45 years, has their cholesterol measured. The frequency of testing will depend on your results.
 
“If you’re under 45, have your cholesterol checked if you have one other risk factor for heart disease. These include a family history, if you’re a smoker, if you’re overweight or if you have high blood pressure,” says D’Angelo.
 
“Everyone should ‘know their numbers’ and take control of their own health. A lot of people are scared of what they might discover, but prevention is better than cure.”
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