Cholesterol is a fatty substance that circulates around the body via the bloodstream. It’s required for a number of processes, including building the structure of cell membranes, and producing hormones, Vitamin D, and bile acids. Cholesterol is made by your body and is also a by-product of your diet. About 75% of your cholesterol is produced in the liver, other organs and cells. The remaining 25% is influenced by your diet.1
There are two types of cholesterol:
- Low density lipoprotein (LDL): Also known as ‘bad’ cholesterol, high levels of LDL can clog up your arteries and lead to heart disease.
- High density lipoprotein (HDL): Also known as ‘good’ cholesterol, HDL helps remove excess cholesterol from the cells, including in the arteries, and transport it back to the liver where it’s broken down.
Even though cholesterol is necessary for our body to function correctly, too much of the wrong kind — LDL cholesterol – is a health risk. This can build up in the walls of your arteries and form plaque. Plaque can block the arteries, making it harder for blood to flow through. This may lead to heart disease and stroke.
The only way to know your cholesterol levels is through a blood test. A cholesterol test measures the amount of cholesterol and other lipids (fats) in your blood, and is usually done after a period of fasting. A cholesterol test will measure:
- LDL cholesterol in your blood
- HDL cholesterol in your blood
- Triglycerides — a type of fat in your blood that can also increase your risk of heart disease
- Total cholesterol — the overall level of cholesterol in your blood
While there are general recommendations as to what healthy cholesterol levels should be, your target levels will depend upon other risk factors you may have for cardiovascular disease. To find out what level you should aim for, speak to your doctor or book a cholesterol test.
The main cause of high cholesterol levels is our diet. In particular, consuming:
- Saturated and trans fats — found in some meats, dairy products, chocolate, baked good, fried and processed foods
- Cholesterol — found in animal products like meat and cheese
Other factors2 that can also lead to high cholesterol levels include:
- diabetes – this condition can upset the balance between HDL and LDL levels3
- liver or kidney disease – liver disease can hinder the ability to clear cholesterol4, while people with kidney disease are more likely to have high cholesterol levels5
- Polycystic ovary syndrome, which is linked to insulin resistant, causing weight gain and higher levels of triglycerides, and lower levels of HDL cholesterol6
- pregnancy or other conditions that increase levels of female hormones – cholesterol levels increase naturally during pregnancy to help provide nutrition to grow the baby7
- underactive thyroid – this makes it hard for your body to remove LDL cholesterol, leading to higher levels of ‘bad’ and overall cholesterol8
- some medications
Most people with high cholesterol levels often have no symptoms, which is why testing is so important. Someone with blockages in their arteries caused by high cholesterol may experience chest pain, a heart attack or a stroke without warning.
Your ideal blood pressure will be determined by your doctor, who will also take into account any other risk factors.
Lowering your cholesterol
If your cholesterol levels are too high, your doctor will advise the best course of action. The most important thing you can do to lower your cholesterol is to adopt healthy lifestyle measures. These include:
Eating the right foods in moderate portions can reduce your levels of LDL cholesterol, and increase your levels of HDL cholesterol. In particular, you should aim to:
- eat more fresh fruit, vegetables and wholegrain foods
- eat fish (fresh or canned) at least twice a week
- eat foods rich in soluble fibre and healthy fats (e.g. nuts, legumes and seeds)
- choose lean meats over fatty or processed meats
- replace butter with polyunsaturated margarine
- choose low or reduced-fat dairy products
- limit cheese and ice-cream to twice a week
- reduce the total amount of fat in your diet
Regular activity can also help you improve your overall cholesterol by increasing your HDL levels and reducing your LDL levels. You should aim for at least 30 minutes of moderate-intensity exercise each day. Examples include walking, running, dancing or cycling.
Changing some of your lifestyle habits can also help lower your cholesterol and risk of cardiovascular disease. These include:
- reducing your alcohol intake to no more than two drinks a day and avoiding binge drinking
- quitting smoking
- losing excess weight
- controlling blood sugar levels if you have diabetes
For some people, diet and lifestyle measures may not be enough to reduce cholesterol levels sufficiently. If this is the case for you, your doctor may recommend medication.
Having regular health checks is an important part of looking after your overall health. At TerryWhite Chemmart we can help you keep track of your cholesterol and overall health with our Health Checks.
General advice only – this information should not replace the information provided to you by your health care professional. If symptoms are severe or persist, please speak to your health care professional. Information current as of date of publishing.
1 Healthline, What Foods Impact Your Cholesterol Level? https://www.healthline.com/health/where-is-cholesterol-found
2 Medical News Today, What causes high cholesterol?, https://www.medicalnewstoday.com/articles/9152
3 Diabetes Australia, Cholesterol, https://www.diabetesaustralia.com.au/cholesterol
4 Healthline, Liver function complications, https://www.healthline.com/health/liver-cholesterol#liver-complications
5 National Kidney Federation, Cholesterol and kidney disease, https://www.kidney.org.uk/cholesterol-and-kidney-disease
6 John Hopkins Medicine, Polycystic Ovarian Syndrome: How Your Ovaries Can Affect Your Heart, https://www.hopkinsmedicine.org/health/conditions-and-diseases/polycystic-ovarian-syndrome-how-your-ovaries-can-affect-your-heart
7 Healthline, How to Manage Your Cholesterol Levels During Pregnancy, https://www.healthline.com/health/pregnancy/manage-cholesterol-levels-during-pregnancy
8 Medical News Today, How are thyroid and cholesterol related?, https://www.medicalnewstoday.com/articles/322618#cholesterol