What is cholesterol?
Cholesterol is a natural substance that is essential for a person to be healthy. It’s an important part of normal cell membranes and it’s needed to make other things in the body – such as hormones – including the sex hormones and adrenaline, bile and vitamin D. It’s a fatty substance known as a lipid and is mainly made in the liver – although some cholesterol is obtained from the food we eat.
Whilst cholesterol is important in the normal, healthy body, high levels of cholesterol (hypercholesterolaemia) can be dangerous as it increases the risk of serious health problems.
What do you need to know about the types of cholesterol?
Cholesterol is carried in the blood bound to proteins and when bound together in this way they are called lipoproteins. Lipoproteins fall into two main groups known as high-density lipoproteins (HDL) and low-density lipoproteins (LDL).
HDL-cholesterol (’’good’’ cholesterol)
HDL carries cholesterol from the cells back to the liver, where it is destroyed or removed from the body as waste. HDL is therefore referred to as ‘good cholesterol’ and higher levels can have a positive effect on health.
LDL-cholesterol (’’bad’’ cholesterol)
LDL carries cholesterol from the liver to the cells of the body. If there is more cholesterol than the body needs, this cholesterol can build up in the walls of arteries that carry blood to our major body organs including the heart and brain. This build-up of cholesterol can increase the chances of the arteries becoming clogged and therefore narrowing. This, in turn, can cause heart attacks, strokes, thrombosis, angina, or other serious problems. For this reason, LDL is often referred to as ’bad cholesterol’.
What cholesterol levels are normal?
It is possible to determine whether you have high cholesterol by a simple blood test. A GP may ask you to have this blood test if he or she thinks you may be at risk from high cholesterol because you have certain medical conditions such as heart disease, high blood pressure, stroke or mini-stroke, diabetes or thyroid problems. You may also be asked to have a cholesterol test simply because you are overweight, over the age of 40, or if you have a family history of high cholesterol or cholesterol-related problems. A combination of these things will increase the likelihood that you will be asked to take a test. The blood is normally taken first thing in the morning to ensure that all food you have eaten has been digested and so will not affect the results of the test.
If you think that you need a cholesterol test you should speak with your GP. It is now also possible to have a cholesterol level test conducted by the Pharmacy2U Online Doctor service for a fee using a small sample of blood taken from a finger prick. If you would like to do a blood test, please carry out a cholesterol consultation and our GP will authorise the test if it is deemed appropriate for you.
The results from your blood test will provide a measure of your total cholesterol level, your LDL level, your HDL level and the HDL level as the percentage of LDL.
The accepted levels for a healthy adult are as follows:
- Total cholesterol - 5 mmol/L or less
- LDL - 3 mmol/L or less
- HDL - 0.9-1.5 mmol/L
- HDL (%) - 20% and above
People at high risk of cholesterol-related problems should have lower levels of total cholesterol (4 mmol/L or less) and LDL (2 mmol/L or less). If your cholesterol levels are higher than normal, you may be at risk.
What are the risks associated with high cholesterol?
Evidence strongly supports the fact that high levels of cholesterol significantly increase the risk of a narrowing of the arteries, also known as atherosclerosis. The arteries become partially blocked by cholesterol and other fatty substances. These blockages are called atheromas or plaques. This is serious because the blockages reduce the blood flow to the important parts of the body where it is needed, stopping them from working properly. Depending on which artery is narrowed, this can cause muscle pain in the legs, heart disease and, in men, erectile dysfunction. If the plaque or blockage breaks away from the wall of the artery it can then block an artery completely causing a stroke or a heart attack. Atherosclerosis is also worsened by high blood pressure, smoking, being overweight and diabetes. These factors in combination with high cholesterol can be very dangerous.
What are the causes of high cholesterol?
There are a number of factors that can contribute to high cholesterol levels.
Lifestyle choices are important. A diet high in saturated fats can contribute to high cholesterol. A sedentary lifestyle will also create higher cholesterol, so people who do not take regular exercise are thought to be at a higher risk. Smoking stops HDL from carrying cholesterol back to the liver for destruction and so this is also bad news. Drinking excessive alcohol can also increase cholesterol levels.
Genetics is another major factor. Some people are genetically predisposed to high cholesterol, including certain ethnic groups (Indian, Pakistani, Bangladeshi or Sri Lankan). In addition, some people have high cholesterol that runs in the family. This is called familial hypercholesterolaemia, affects about 1 in 500 people, and is inherited from a parent. In this case, lifestyle is not the cause of the problem and extremely fit and healthy people can have high cholesterol – no matter how healthy their lifestyle.
How can you lower cholesterol levels?
Although high cholesterol levels can be very damaging, it is possible to treat the condition in a number of ways.
Lifestyle changes are important and should always be attempted. Try looking at the following:
Change your diet
Maintain a diet that is low in saturated fats, and high in fresh fruit, vegetables and wholegrain fibre.
If you smoke, it's very important to quit if you want lower your cholesterol. If you need assistance, please visit the Pharmacy2U Online Doctor section on smoking cessation.
Reduce alcohol intake
Lessening your intake of alcohol can help to improve cholesterol levels if you currently drink more than the recommended amounts.
Take up exercise
Ensure that you carry out rigorous exercise at least three times a week.
In some cases, lifestyle changes will not be enough to reduce cholesterol to acceptable levels. If you have been making the above changes over the last few months and you are at risk of dangerous consequences of high cholesterol, your doctor may wish to prescribe medication.
The most commonly used medicine and the first choice for doctors for treating high cholesterol is a group of medicines known as statins. Statins reduce the production of cholesterol in the liver by blocking an enzyme. The most common statins are:
Like all medicines, statins can cause side effects and these vary between each medicine. If the side effects of one statin are unacceptable, your doctor can prescribe an alternative one to see if it’s more suitable to you.
The Pharmacy2U Online Doctor service can offer prescriptions for these medicines should the doctor decide that is appropriate for you. This may be based on a consultation alone or may require you to submit a blood test. Our experienced GP will advise you if a blood test is required.
Ezetrol (ezetimibe) is normally used in severe cases of high cholesterol that does not respond to statins alone. It can be used on its own in some cases including when a patient cannot tolerate statins. It works by blocking the absorption of cholesterol from food in the intestines. It is often better tolerated than statins. The Pharmacy2U Online Doctor can prescribe Ezetrol if it is appropriate for you.
Many experts believe that Omega-3 fatty acids are beneficial to health and are often used in combination with statins to lower triglyceride levels which are often raised at the same time as cholesterol. Omacor is a commonly used brand and can be prescribed by the Pharmacy2U Online Doctor service after a high cholesterol consultation.
What are the differences between the cholesterol-lowering medicines?
In most cases, and as long as your health profile suggests they are safe for you, statin drugs are recommended first because they are known to be very effective at lowering LDL-cholesterol levels and are very well tolerated by most people.
All statins work in the same way, so the choice of a particular statin for you as recommended by the doctor comes down to other factors. These can include their cost, how they are taken, and what other medicines you might be taking. For example:
- Some statins are available generically (for example, branded Lipitor is also available as generic atorvastatin).The generic version works in just the same way as the branded version, but is less expensive.
- Some statins are best taken in the evening (for example, simvastatin), but others can be taken at any time of day.
- Some statins should not be taken with other medicines or foods (for example, simvastatin should not be taken with warfarin or grapefruit juice, but rosuvastatin does not interact significantly with either).
If you do not wish to take a statin, or if you have had side effects with them before, Ezetrol (ezetimibe) may be a good choice. There is another group of cholesterol-lowering medicines, called ‘fibrates’, which your own doctor may consider prescribing in these situations.