What is cholesterol?
Cholesterol is a type of fat in our blood which is produced by the liver. Everyone has cholesterol. Some of this cholesterol comes from the food that we eat. Our bodies need a certain amount of cholesterol for normal cell function, to help digestion and produce certain hormones. So not all cholesterol is bad.
Why is a healthy cholesterol important?
If your total cholesterol is high, it can mean that you have a lot of LDL (bad) cholesterol in your blood. Too much LDL cholesterol can be harmful because it sticks to the inside walls of your arteries. This can lead to fatty material building up – in a process called atherosclerosis. It makes it harder for blood to flow through, which can lead to a stroke or heart attack.
Having high cholesterol affects people of all ages. Making small changes now can make a big difference to your life now and in the future, especially if you already have heart disease or a family history of it.
What are the types of cholesterol?
There are two main types of cholesterol: HDL and LDL
HDL (high-density lipoprotein) known as ‘good’ cholesterol because it can help keep bad cholesterol in check by transporting it away from the arteries to the liver, where it is broken down and removed from the body. HDL cholesterol has been associated with a reduced risk of coronary heart disease.
LDL (Low density lipoproteins) – LDL is known as ‘bad’ cholesterol because it sticks to the artery walls forming a fatty plaque and causes narrowing of the arteries. This narrowing reduces the blood supply to your heart and brain. If the arteries that carry blood to your heart get damaged and blocked, it can lead to a heart attack. If this happens in the arteries that carry blood to your brain it can lead to a stroke.
Triglyceride is another type of fat in our blood and it is also affected by what we eat and drink (e.g. eating a lot of sugary processed foods can make you more likely to have a high triglyceride level). Triglycerides can be raised in diabetes, obesity, kidney disease, with an underactive thyroid and too much alcohol. Triglycerides can also contribute to the narrowing of the artery walls, increasing your risk of heart disease.
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.
Things that can cause high cholesterol
What steps can you take to keep your cholesterol at a healthy level?
A cardio-protective Mediterranean diet is the first line dietary approach for the prevention of heart disease and stroke. Research around the Mediterranean diet has shown that people following this approach have a reduced risk of developing conditions such as diabetes, high blood pressure and raised cholesterol, all of which are all risk factors for heart disease.
However, it must be remembered that the Mediterranean diet is not just a diet, it also includes a number of lifestyle factors such as, increased physical activity and smoking cessation, all of which have also been shown to be important to reduce the risk of heart disease. At its core, the Mediterranean diet is an entire dietary pattern rich in fruits and vegetables, wholegrains, olive oils, beans, nuts, seeds, and legumes in addition to oily fish. It also contains moderate amounts of low fat dairy while consumption of red and processed meats along with sweets and treats, is low. The Mediterranean diet is high in good fats (mostly monounsaturated fats that have been shown to lower cholesterol levels) which come from nuts, seeds and olive oils.
The Mediterranean diet can be used in conjunction with specific dietary and lifestyle advice related to individual risk factors which are present such as high cholesterol, diabetes, high blood pressure, weight.
To keep your overall cholesterol profile healthy, in addition to a healthy diet, the evidence recommends regular physical activity, alcohol intake limited to moderation, achieving and maintaining a healthy weight and if you smoke looking at supports to help you quit . Your dietitian or GP will be able to provide you with further tailored dietary advice dependent on your cholesterol profile.
Is it possible to increase your good cholesterol?
When it comes to specific lifestyle advice for increasing your good (HDL) cholesterol the evidence supports:
Signs and symptoms of high cholesterol
People with high cholesterol often have no noticeable symptoms. The only way to know if you have high cholesterol is to go to your doctor and have a blood test. Your blood is then checked for levels of good (HDL) cholesterol, bad (LDL) cholesterol and triglycerides, as well as getting a total cholesterol result. If you have been told you have a high cholesterol level, you have too much ‘bad’ cholesterol in your bloodstream which increases your risk of having a heart attack or stroke. But a high level of ‘good’ (HDL) cholesterol can help keep that ‘bad’ (LDL) cholesterol in check.
How often should I have my cholesterol checked?
The frequency you should have your cholesterol checked would vary for individuals, based on their family history, on whether they have a pre-existing illness or condition, on their age and other factors. Assessments should be individualised. However, we would recommend that for individuals with no pre-existing condition or family history of heart disease and stroke that individuals over 40 years should also have a cholesterol check and then every 4 to 5 years after that. This is just a guide as other factors would need to be taken into consideration such as physical activity levels, alcohol intake, weight and whether the person smokes.
Getting your cholesterol checked
Your cholesterol can be measured by your doctor, who knows your family history. If a family member has high cholesterol, heart disease or has had a stroke, it’s really important you ask your doctor to do a cholesterol test. You can ask for this on any visit.
If your results show a blood cholesterol level greater than five mmol/l, or if your doctor is concerned about your HDL (good) or LDL (bad) cholesterol, they will arrange for another test. You will need to fast for 12 hours to get more information on your HDL and LDL cholesterol.
As well as HDL and LDL levels, the more detailed test will show triglyceride levels – another type of fat. Anyone can have high levels of triglyceride, but it is more likely if you have a higher weight, a high intake of alcohol; eat a lot of sugary foods; or are not very active.
The numbers to watch out for
If you have previously had a heart attack, bypass surgery or angioplasty, it’s also very important that you keep your LDL at or below 2.5 mmol/l. Your doctor will most likely suggest medication together with healthy eating and other lifestyle changes.
Cholesterol And Triglycerides Healthy levels:
|Total cholesterol:||No more than 5 mmol/l|
|LDL cholesterol:||No more than 3 mmol/l|
|HDL cholesterol:||More than 1 mmol/l|
|Triglycerides:||No more than 2 mmol/l|
For people with heart disease or diabetes
|Total cholesterol:||No more than 4.5 mmol/l|
|LDL cholesterol:||No more than 1.8 mmol/l|
If you need to change any aspects of your cholesterol or triglyceride levels, your doctor will advise you on changes in lifestyle and may recommend medication. If you are prescribed medication, please make sure you follow the instructions carefully.
(Page last updated 3rd November 2020)