High cholesterol

What is high cholesterol?

There are two main types of cholesterol: high-density lipoprotein (HDL), which is known as the ‘good’ cholesterol, and low-density lipoprotein (LDL), which is the ‘bad’ cholesterol.

Cholesterol is a fat-like, waxy substance in the blood which the liver produces. It is important for the body as it protects nerves, makes cell membranes and certain hormones. But high levels of cholesterol can be dangerous.

High cholesterol can cause fatty deposits to gather in the arteries. Gradually, these deposits grow and interrupt the flow of blood through the arteries. This can form blood clots and increase the risk of heart attack or stroke.

What are the different types of cholesterol?

HDL (high-density lipoprotein) is called “good” cholesterol. It takes cholesterol to your liver, where it is flushed out of your body. This reduces the risk of cholesterol collecting at the wall of your arteries, which helps to keep you healthy.

LDL (low-density lipoprotein) is called “bad” cholesterol. It takes cholesterol directly to your  arteries. Excess amounts of cholesterol sometimes cause a plaque buildup which increases the risk of blood clot in the arteries, which can eventually lead to a heart attack or stroke.

There’s also very-low-density lipoprotein (VLDL) produced in the liver and carried through your bloodstream into your body. VLDL mainly carries triglycerides into your blood vessels. Like LDL, VLDL is also considered “bad” cholesterol as too many triglycerides can build up deposits in your artery walls and make them narrow. This restricts blood-flow, and can also lead to serious health issues.

Who gets high cholesterol?

Poor cholesterol levels are usually found in adults, particularly those over the age of 40. This is because as you get older, your body becomes worse at removing LDL cholesterol. You are also more likely to have high cholesterol if you’re a smoker, a drinker, have a bad diet, lead a sedentary lifestyle or are overweight or obese.

It can occur in children, usually by an inherited disorder called familial hypercholesterolemia, which doesn’t let the body recycle LDL cholesterol properly. It is important that you check your cholesterol levels regularly, particularly if you’re at risk, so that you can begin treating it before it creates bigger problems.

How common is high cholesterol?

It’s unclear just how common high cholesterol is, partly because so many people have it without knowing. But in 2008, the global prevalence of raised total cholesterol among adults was estimated at 39% (37% for males and 40% for females). ^[1] More recent statistics say that in England, in 2021, the prevalence of raised total cholesterol in adults was 59% (56% for men and 61% for women).^[2]

So it’s definitely common. And if global obesity continues to rise then it’s only going to become more widespread.

What causes high cholesterol?

Many factors can be responsible for a high amount of cholesterol in your body. Poor lifestyle choices like an unhealthy diet (foods high in saturated fat, trans fat or refined sugars), lack of physical activity, drinking excessive alcohol and smoking can increase your cholesterol levels.

Some health factors which can also cause high cholesterol levels include obesity, family history of high cholesterol, increasing age or being of South Asian origin. Medical conditions like diabetes, high blood pressure, kidney or liver problems, underactive thyroid gland and polycystic ovary syndrome can increase the amount of ‘bad’ cholesterol in your body.

High cholesterol can cause a plaque build up called atherosclerosis to accumulate in the arteries. Gradually, this buildup grows and forms a clot that interrupts the flow of blood through the arteries. This often causes heart attacks, strokes or coronary artery diseases.

What are the symptoms of high cholesterol?

High cholesterol does not have any specific symptoms. You might know about it only during life-threatening complications.

The only way to be aware about your cholesterol levels is to get it checked regularly. A simple blood test will give you the levels of good (HDL) cholesterol, bad (non-HDL) cholesterol and triglycerides in your body.

Can high cholesterol lead to other problems?

Yes. High cholesterol has been linked to an increased risk of people developing serious and sometimes life-threatening problems down the line. High blood cholesterol can lead to a condition called atherosclerosis: where excess plaque builds up in your blood vessels.

This can lead to coronary heart disease, heart attack, stroke or sudden cardiac arrest.