Photograph shows cheese, meat with fat rind and donuts – foods high in animal fats should be avoided or reduced by people with high cholesterol.

The most effective way to lower your cholesterol is to reduce the amount of animal fat in your diet.

The facts about cholesterol levels

CSIRO is carrying out research to develop strategies for reducing cholesterol levels, the risk of heart disease and other conditions that are food-related and correctable through modifying our diet.

  • 14 June 2011 | Updated 14 October 2011

Cholesterol

CSIRO is carrying out research in a number of dietary areas to develop strategies for reducing cholesterol levels, the risk of heart disease and other conditions that are food-related and correctable through modification of diet.

High levels of cholesterol are a risk factor for coronary artery disease (heart attacks and angina).

What is it?

Cholesterol is an essential type of fat that is carried in the blood.

All cells in the body need cholesterol for internal and external membranes.

It is also needed to produce some hormones and for other functions.

The body generally makes all the cholesterol it needs.

Some dietary cholesterol is normally excreted via the liver, however eating too much saturated fat leads to excess cholesterol in the blood stream.

Why is high cholesterol a problem?

High levels of cholesterol in the blood stream are a risk factor for coronary artery disease (heart attacks and angina).

If your cholesterol level is 6.5 mmol/L or greater your risk of heart disease is about 4 times greater than that of a person with a cholesterol level of 4 mmol/L.

High blood levels of cholesterol are a risk factor for coronary artery disease (heart attacks and angina).

Not all people with high cholesterol levels get heart disease.

About 30 per cent of the community will die of heart disease and most of these will be over 65 years old.

Heart disease usually takes 60-70 years to develop, but if you discover your cholesterol level is high you should see your doctor within the next 2-3 months, not necessarily tomorrow.

Other risk factors for heart disease include smoking, high blood pressure and obesity.

Cholesterol - the good and the bad

Cholesterol is carried in the blood stream in particles called lipoproteins.

These are named according to how big they are:

  • the very large particles are called Very Low Density Lipoproteins (VLDL)
  • the intermediate size ones are called Low Density Lipoprotein (LDL) and these particles cause heart disease
  • the smallest particles are called High Density Lipoproteins (HDL) and these particles actually protect against heart disease.

What to do if your cholesterol level is high

The most effective way to lower your cholesterol is to reduce the amount of animal fat in your diet by various means.

You could:

  • reduce cheese intake and/or substitute low fat varieties
  • choose reduced fat milks
  • use polyunsaturated or monounsaturated margarine or oils instead of butter
  • choose lean cuts of meat and remove all visible fat
  • eat skinless chicken, fish or beans
  • beware of pies, pasties, fish and chips and commercial cakes (hidden fat)
  • make cakes at home with polyunsaturated fat, cook chips with polyunsaturated or monounsaturated oil
  • lose weight if overweight.

If you make a number of changes to your diet you can expect your cholesterol to fall by 10 per cent.

About 15 per cent of people will see no change and another 15 per cent will see changes of 20-30 per cent.

How high is high?

If your cholesterol is between 5.5 and 6.5 your risk of heart disease is only increased by a small amount.

Don’t panic but make a few moderate changes to your diet.

However if you already have heart disease, or one of your parents developed heart disease at an early age, (less than 55 years of age) then you need to make bigger changes.

If your cholesterol is higher than 6.5 then you need to make more changes.

If despite changes to your diet your cholesterol level remains above 6.5 you may need medication, especially if you have the other risk factors mentioned or you have a family history of heart disease- see your doctor.

What about triglycerides?

Triglycerides are a stored energy source.

Most of the triglyceride is found in the very large particles, the VLDL.

Under some circumstances high blood triglyceride can be a risk factor.

If your cholesterol is high (greater than 6.5) and your HDL cholesterol is low (less than 0.9) then triglycerides can increase the risk of heart disease if they are greater than 1.7.

Triglyceride levels greater than 10 can cause inflammation of the pancreas which is a very serious condition.

How can I lower my triglyceride?

Reduce your intake of animal or hard vegetable fats, lose weight and reduce alcohol intake.

Alcohol is very powerful at elevating triglyceride.

See your family doctor if it remains elevated as you may require medication.

Find out more about CSIRO's Preventative Health Flagship.