What is cholesterol?
Cholesterol is a fatty substance in our blood, which is produced naturally in the liver. Everyone has cholesterol. We need it to stay healthy because every cell in our body uses it. Some of this cholesterol comes from the food that we eat.
There are two main types of cholesterol – one is 'good' and the other is 'bad'. Having too much 'bad' cholesterol can cause problems. It can clog up the arteries carrying blood around your body. This can cause heart and circulatory diseases like a heart attack or stroke.
Cholesterol is carried around the body through our bloodstream by proteins (the building blocks of our cells). When cholesterol and proteins are combined, they are called lipoproteins.
'Good’ and ‘bad’ cholesterol
There are several types of lipoproteins, but they can generally be divided into two main types:
Non-high density lipoproteins (non-HDL) delivers cholesterol from the liver to cells around your body. This is known as ‘bad’ cholesterol because if you have too much it can stick to the walls of your blood vessels and can stay there. This can clog up the blood vessels, causing them to become stiff and narrow which can lead to a heart attack or stroke.
High-density lipoproteins (HDL) are known as ‘good’ cholesterol because it gets rid of ‘bad’ cholesterol from your blood vessels. It takes the cholesterol that you don’t need back to the liver where it is broken down to be passed out of your body, thereby reducing your risk of heart and circulatory disease.
You may hear bad cholesterol being referred to as low-density lipoprotein or LDL. This is because LDL was previously used as the main measure of bad cholesterol. Research now tells us we also need to consider other parts of ‘bad’ cholesterol, known as IDL, VLDL and lipoprotein(a). These parts of ‘bad’ cholesterol are collectively known as non-HDL cholesterol.
Our blood contains another type of fatty substance called triglycerides. This is stored in the body's fat cells and is also found in foods such as dairy products, meat and cooking oils. You may see this on your cholesterol reading results because triglycerides can contribute to the narrowing of the artery walls, which can increase your risk of heart disease.
What does a high cholesterol level mean?
When people talk about keeping their cholesterol down, they usually mean their total cholesterol level. This is worked out by measuring your 'good' HDL cholesterol, your 'bad' non-HDL cholesterol and your triglyceride level.
If you have been told you have a high total cholesterol level, you have too much 'bad' cholesterol in your bloodstream which means you are more likely to have a heart attack or stroke. But a high level of 'good' (HDL) cholesterol can help keep that 'bad' (non-HDL) cholesterol in check.
There is no specific target cholesterol level because your doctor is looking at your overall risk of developing heart and circulatory disease including whether you smoke or have high blood pressure.
For a healthy heart, the aim is to have a low non-HDL (bad) level and a high HDL (good) level.
What causes high cholesterol?
Anyone can get high cholesterol, and it can be caused by many different things. Some things you can control like lifestyle habits, others you can’t. As long as you take care of the things you can control, you’ll help lower your risk of heart and circulatory disease.
Things that cause high cholesterol you can control
Things that cause high cholesterol you can't control
What can I do to lower my cholesterol?
Making some simple lifestyle changes may be all that you need to bring your cholesterol down to a good level. Here are some ways you can do this.
Eat a healthy balanced diet
Eating more fruit, vegetables and wholegrain is better than eating foods high in saturated fat and sugar. Saturated fat and trans fats can increase your total cholesterol level and your non-HDL cholesterol (bad) level which increases the risk of fatty deposits building up in your arteries.
Saturated fat is mainly found in
- fatty meats
- palm and coconut oil.
Trans fats are usually found in processed foods like biscuits, cakes, fast food and some margarines and spreads. You can replace these fats with the healthy monounsaturated and polyunsaturated fats such as
- olive, rapeseed or sunflower oils and spreads
- vegetable oil spreads
- oily fish.
Choose more wholegrains and foods that are high in soluble fibre as this can help lower cholesterol such as
- fruits and vegetables.
Be active for at least 30 minutes a day
Regular physical activity strengthens your heart and reduces your 'bad' cholesterol. Being active helps increase your 'good' HDL cholesterol while helping your body move the 'bad' non-HDL cholesterol to your liver where it will be disposed of.
You don’t have to join a gym or take up a sport, just look for chances to move more every day. Staying active is great way to keep your heart healthy.
Quitting smoking can help to lower your cholesterol and improve your heart health. Smoking stops 'good' cholesterol doing its job of getting rid of your 'bad' cholesterol. Speak to your doctor about how to stop smoking as soon as you can. Not smoking will really help you avoid heart disease.
Will I need to take medication?
If your cholesterol is very high and if lifestyle changes are not enough, your doctor might suggest controlling it with medication. Whether or not you need to take cholesterol-lowering medicine depends on your overall risk of cardiovascular disease.
Cholesterol-lowering medicines such as statins are prescribed for people who are at greatest overall risk of cardiovascular disease. If you have questions about your medicines, speak with your doctor or call our Heart Helpline on 0300 330 3311. You can also look at our publications for more information.
Tackling high cholesterol
In 1989, we participated in the first big trial that looked at whether statins could help stop people with high cholesterol levels from developing heart disease.The people who took the drug reduced their risk of having a first-time heart attack by nearly a third.
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