High cholesterol

What cholesterol is, and why too much matters

Cholesterol is a waxy, fat-like substance found in every cell. Your body uses it to make hormones, vitamin D and substances that help you digest food, and it makes all the cholesterol it needs. Cholesterol also comes from animal foods such as egg yolks, meat and cheese.

Too much cholesterol can combine with other substances to form plaque that sticks to artery walls. This is called atherosclerosis. Two types are often mentioned: HDL, sometimes called good cholesterol, carries cholesterol back to the liver to be removed, and LDL, sometimes called bad cholesterol, adds to the plaque.

Symptoms

High cholesterol does not usually cause symptoms. You can only find out from a blood test. WHO notes that disease of the blood vessels often causes no symptoms, and a heart attack or stroke may be the first sign, which is why testing before anything goes wrong is worthwhile.

Causes and who is more likely to have it

• Being over 50, being a man, or having been through the menopause.
• South Asian or sub-Saharan African origin.
• A family history. An inherited form called familial hypercholesterolaemia causes high levels from a young age.
• Eating a lot of saturated fat, not exercising enough, being overweight, smoking and drinking alcohol.
• Other conditions such as diabetes or chronic kidney disease, and some medicines.

MedlinePlus adds that long-term stress may play a part, and that cholesterol tends to rise with age, although children and teenagers can have high cholesterol too.

How it is tested

The usual test takes a blood sample from your arm, which goes to a laboratory, with results in a few days. Most people do not need to fast beforehand, although you might be asked not to eat for up to 12 hours. A finger-prick test gives a result in a few minutes. The NHS suggests asking for a test if you have never had one and you are over 40, overweight, or high cholesterol or heart problems run in your family.

The NHS gives these as a guide for healthy adults:

Your own target depends on your age, other conditions and your overall risk. A doctor combines your result with things like your blood pressure to estimate your chance of a heart attack or stroke over the next 10 years. Our guide to common blood tests explains the lipid profile.

How to lower it

The NHS suggests eating more oily fish such as salmon and mackerel, olive or rapeseed oil, brown rice and wholegrain bread, nuts, seeds, fruit and vegetables. It suggests less fatty meat and sausages, butter, ghee and lard, cream, cheese, cakes and biscuits, and food made with coconut or palm oil.

• Aim for at least 150 minutes of moderate exercise or 75 minutes of vigorous exercise a week. Brisk walking, swimming and cycling are good places to start.
• Stop smoking, which raises cholesterol and the risk of heart attack and stroke.
• Cut down on alcohol and have several drink-free days each week.

If lifestyle changes alone do not bring your cholesterol down enough, or your risk is high, a doctor may talk to you about medicine. Statins are the most common type. You should keep up the lifestyle changes alongside any medicine.

Complications to know about

Plaque narrows the arteries that supply the heart, which is coronary artery disease. If a patch of plaque breaks open, a clot can form and block blood flow, causing angina or a heart attack. Plaque in the arteries to the brain and legs can lead to stroke and peripheral arterial disease. WHO counts raised blood lipids, alongside raised blood pressure and blood glucose, among the measurable signs of higher risk of heart attack and stroke.

When to see a doctor, and when to call 998

Call 998 for pain or discomfort in the centre of the chest, or in the arms, left shoulder, elbows, jaw or back, especially with shortness of breath, feeling sick, a cold sweat or feeling faint. Also call 998 for sudden weakness or numbness of the face, arm or leg, sudden confusion, difficulty speaking or seeing, or a sudden severe headache. These can be signs of a heart attack or stroke.

Book a test if you are over 40 and have never had one, or if heart disease or high cholesterol runs in your family. If you already have a result, a GP, family medicine, internal medicine or cardiology doctor on medicAI can go through it with you by video. Each works at an independent facility licensed by DHA or DoH, which is responsible for your care.