By Muhammed Haroon –

Almost 60% of people in the UK have high cholesterol, and most don’t even know it.

There are no warning signs, but over time, high cholesterol can quietly damage your arteries and increase your risk of a heart attack and a stroke.

Consultant Cardiologist, Dr Zoe Astroulakis, explains what cholesterol really means for your health, and clears up some common myths.

What is Cholesterol?

Cholesterol is a fatty substance made mostly by your liver.

Your body needs it because it helps build cells, make hormones and digest food.

The problem isn’t cholesterol itself; it’s having too much of the wrong type of cholesterol in your blood.

Why Does High Cholesterol Matter?

Over many years, “bad” cholesterol, called LDL (low-density lipoprotein), can stick to the inside of your arteries.

Think of it as grease and limescale building up in a pipe.

As this build-up of “bad” cholesterol grows, blood has less space to flow through, and if a piece breaks off, it can cause a blood clot, which may lead to a heart attack (if it happens in the heart) or a stroke (if it happens in the brain).

In the UK, 1 in 4 deaths are caused by a heart attack or stroke.

The worrying part? The damage often starts in your 30s and 40s.

Isn’t Total Cholesterol the Only Number That Matters?

No. Doctors look at three main things in your blood test:

• The “bad” cholesterol (LDL – low-density lipoprotein)
• The “good” cholesterol (HDL – high-density lipoprotein)
• Triglycerides, which are another type of fat in the blood

They also look at your age, blood pressure, whether you smoke, and whether you have diabetes.

All of this goes into a risk calculator to estimate your chance of a heart attack or stroke in the next 10 years.

“I’m Slim and Healthy – So I’m Fine… Right?”

Not exactly. You cannot tell your cholesterol level just by looking at yourself in a mirror.

You can be slim, exercise regularly, and still have high cholesterol; the only way to know is with a blood test.

That’s why the NHS offers free health checks to people aged 40 to 74.

Some people also inherit high cholesterol, called hypercholesterolemia, which affects about 1 in 250 people.

These individuals can have very high cholesterol from birth.

Do I Need to Fast Before a Blood Test?

Not usually. But some doctors still recommend fasting, especially if they want a clear reading of triglycerides.

If you have diabetes, fasting is often advised.

What Should My Cholesterol Be?

For people at low risk, LDL (“bad”) cholesterol should be below 3.00mmol/L.

If you have already had a heart attack or stroke, your LDL (“bad”) cholesterol level should be below 1.8mmol/L.

Your doctor will decide what’s right for you based on your overall risk.

Do I Need to Cut Out All Fat?

No, this is a common misconception. It’s not about removing all fat; it’s about choosing healthier fats.

Here are some tips on what you can try:

• Cut down on red meat and processed foods
• Reduce butter and saturated fats
• Use olive oil instead
• Eat oily fish
• Eat more nuts and seeds
• Eat more fibre, such as oats, beans, lentils and whole grains

Small changes such as these can start improving cholesterol levels within weeks.

Aren’t Women Protected From Heart Disease?

Before menopause, women have some protection from the hormone oestrogen.

After menopause, cholesterol levels often rise, and the risk of heart disease increases quickly.

Within 10 years, women’s risk of heart disease can match that of men.

Women who’ve had pregnancy complications like pre-eclampsia or gestational diabetes may also have a higher long-term risk of heart disease.

What About Statins? Aren’t They Dangerous?

Statins are one of the most studied medicines in the world. They reduce the risk of a heart attack and a stroke by 25-30%

Statins work by lowering “bad” cholesterol, reducing inflammation in the arteries and making fatty buildups less likely to burst.

Statins, just like all medicines, can cause side effects in some people, but for those who are at higher risk, the benefits usually outweigh the risks.

If someone doesn’t react well to statins or their body can’t tolerate them, there are now other treatments available.

Do Statins Cause Diabetes?

There is a small link between statins and type 2 diabetes, but many people who develop diabetes while on statins already had higher blood sugar levels beforehand.

Doctors usually check blood sugar levels when testing cholesterol.

Can Statins Prevent Dementia?

Some studies suggest statins may lower the risk of certain types of dementia, especially those linked to blood vessel damage.

Research is ongoing, as this isn’t fully understood yet; however, what is clear is that protecting your heart also helps protect your brain.

What is Lipoprotein(a)?

This is a type of cholesterol you may not have heard of. It’s mostly determined by your genes and isn’t changed by diet or exercise.

High levels are linked to early heart attacks, but there is currently no specific treatment for it.

Research is ongoing, and if your level of lipoprotein(a) is high, doctors usually focus on lowering other cholesterol levels even more.

The Bottom Line

From the age of 40 onwards, everyone should know:

• Their weight
• Their blood pressure
• Their cholesterol levels
• Their blood sugar

If you have a family history of heart disease, speak to your GP.

High cholesterol builds up slowly in silence, but the good news is that it can be treated, and heart disease is often preventable.

As Dr Zoe Astroulakis says, the earlier you know your numbers, the more you can do to protect your future health.

For more information, the NHS offers a full guide on getting tested for high cholesterol and how to start lowering it.