There are no external signs of high cholesterol. So you need to regularly test your levels with a blood test. High cholesterol levels can increase your risk of heart disease. But it's possible to lower your levels through lifestyle changes.

What is high cholesterol?

Cholesterol is a fatty substance found in your blood. So if you have high cholesterol, it refers to high levels of this fatty substance in your blood — sometimes called hyperlipidemia. While some cholesterol is essential, if levels get too high it can lead to a build-up of cholesterol on the walls of your arteries. This is called cholesterol plaque and it narrows your arteries and increases your risk of blood clots — putting you at risk of heart disease.

Signs of high cholesterol levels

There aren’t any signs of high cholesterol, so a blood test is the only way to check if you have high cholesterol levels. Raised cholesterol in people as young as 20 years can indicate an increased risk of heart disease later in life. Which is why national guidelines recommend measuring your cholesterol levels regularly from the age of 20.

Regular cholesterol tests are particularly important if you:

  • are overweight or obese
  • smoke
  • have a family history of high cholesterol or heart disease
  • have high blood pressure, coronary artery disease, or diabetes
  • are on medication for high cholesterol and need to track your levels

Blood tests for high cholesterol

A cholesterol test will measure a range of fats in your blood — sometimes called a lipid test. This will usually include measuring your:

  • total cholesterol — your HDL and LDL levels combined
  • LDL cholesterol — the type of cholesterol that can build up on the walls of your arteries if too high
  • HDL cholesterol — helps remove LDL cholesterol from your body so protects against heart disease
  • triglycerides — your body makes triglycerides when you take in more calories than you need

More advanced tests might measure your apolipoprotein levels — these are proteins that transport fats like cholesterol in your blood. Evidence indicates that your apolipoprotein levels are better at predicting your risk of heart disease than your cholesterol levels.

To test your cholesterol levels, you can either collect a venous blood sample or do a home finger-prick blood test.  

What are the risks of high cholesterol levels?

There’s a lot of evidence showing that high blood cholesterol levels are clearly linked to:

  • stroke
  • heart attack
  • angina (chest pain)
  • high blood pressure
  • chronic kidney disease

But keep in mind that over half of people who have a heart attack have normal LDL cholesterol levels. Heart disease is very complex and cholesterol is only part of the picture.

How to lower your cholesterol

There are lots of things you can do to lower your cholesterol naturally:

  • avoid foods high in cholesterol, saturated fats, and trans fats
  • avoid fast food and fried foods
  • eat high-fibre foods, like fruits, vegetables, and whole grains
  • eat lean sources of protein, like chicken, fish, and legumes
  • eat oily fish, like salmon and mackerel
  • exercise regularly — this can help raise your HDL “good” cholesterol
  • lose weight if you’re overweight
  • don’t smoke

The important thing is to keep track of your levels. Making small changes that you can easily stick to, is much more effective than trying to make huge shifts in your lifestyle. 


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Aisling Moran BSc (Hons)

Written by Aisling Moran BSc (Hons)

25th Aug 2021 • 4 min read