What is cholesterol?
Cholesterol forms part of the outer membrane of every single cell. It’s important because it insulates nerve fibres and makes hormones that transport chemical signals around the body. Without it, your body wouldn’t work properly. However, too much cholesterol poses a significant health risk; it increases the risk of heart disease and disease of the arteries.
When saturated fat enters the body, the liver turns it into cholesterol. Excess cholesterol is deposited in the wall of the arteries, where it can build up. This build up of cholesterol is known as plaque, and can cause arteries to harden and narrow. A build up of plaque is called atherosclerosis which can lead to coronary heart disease, such as a heart attack or angina, a stroke or poor blood flow to the lower limbs.
The most recent research has found a worrying two-thirds of adults had high cholesterol levels of 5.0 mmol/L or higher, which is classed as unhealthy and puts them at risk of developing coronary disease.
How do you measure high cholesterol?
To diagnose high cholesterol, you will need to take a test. It’s recommended that adults have their cholesterol level tested every five years, usually in conjunction with a routine physical exam. A blood sample is often collected from a vein in your arm, or from a drop of blood taken from your finger.
The test will measure two types of cholesterol; low density lipoprotein (LDL) and high density lipoprotein (HDL). LDL is commonly known as ‘bad’ cholesterol because it carries cholesterol from the fat to cells in the body. If there is too much LDL cholesterol in the blood, it will be deposited over time and can block your arteries.
HDL is known as ‘good’ cholesterol because it carries cholesterol away from the cells and back to the liver, where it’s broken down. HDL cholesterol can help protect your arteries from blocking.
You cholesterol level will be measured in units called millimoles per litre of blood, shown as ‘mmol/L’. Your total cholesterol should be below 5mml/L and your total LDL cholesterol should be under 3mmol/L.
What causes high cholesterol?
A number of different factors contribute to high cholesterol, including lifestyle factors, treatable factors and fixed factors.
An unhealthy diet is a lifestyle factor which can cause high blood pressure, though dietary cholesterol has little effect on the cholesterol level in your blood. Instead, it’s saturated fat - foods including red meat, hard cheese, pastry, cakes, butter and cream - which have the most impact. Other lifestyle factors include a lack of exercise, which can increase LDL levels; obesity, which means a higher chance of having high LDL and low HDL levels; and drinking too much alcohol, which can increase cholesterol.
Treatable factors, such as hypertension, diabetes, kidney and liver disease or an underactive thyroid can all result in high cholesterol levels.
Fixed factors – factors that are associated with high cholesterol but can’t be changed - include a family history of heart disease or stoke in young age; a family history of a cholesterol-related condition; age, because cholesterol levels grow with age; and ethnicity, because people from India, Pakistan, Bangladesh or Sri Lanka have a higher risk of high cholesterol.
What treatments are available for high cholesterol?
You can treat and manage high cholesterol in many ways, including improvements to your diet, exercising more or taking certain medications.
One of the best ways to treat or prevent high cholesterol, and in particular high LDL levels, is by keeping an eye on your diet and exercise habits. If you become more active and avoid foods high in saturated fat, you should see your cholesterol level fall, because it helps with the production of ‘good’ cholesterol in your body.
You can buy certain medication to treat high cholesterol. Known commonly as statins, this type of medication lowers the concentration of LDL in your blood. However, these medications are usually only prescribed when patients have first made an effort to lower cholesterol through exercise and diet improvements.
Click here to learn more about treatments for high cholesterol levels.