High Cholesterol

Cholesterol is a fatty substance that your body needs in small amounts to build cells and make certain hormones. Most of it is produced by the liver, and some comes from food. It travels in the blood attached to particles called lipoproteins. Low-density lipoprotein (LDL) is often called bad cholesterol because too much can build up in artery walls, while high-density lipoprotein (HDL) is called good cholesterol because it helps carry cholesterol away.

High cholesterol means there is too much harmful cholesterol, or too little protective cholesterol, in your blood. Over many years, excess cholesterol can form fatty deposits inside arteries, making them narrower and stiffer. This process underlies much of the risk of heart attack and stroke.

High cholesterol itself does not usually cause any symptoms. Most people have no idea their level is raised until they have a blood test or until they develop a problem such as chest pain or a heart attack caused by narrowed arteries.

Some people with a strong inherited tendency to high cholesterol may develop visible signs, such as fatty lumps around the eyes, tendons or skin. These are uncommon but can be a clue to an inherited condition that needs assessment.

Cholesterol levels are influenced by both lifestyle and inherited factors. Eating a lot of saturated fat, being overweight, not being active enough, smoking and drinking too much alcohol can all raise harmful cholesterol. Age and family history also play a role.

Some people inherit a condition called familial hypercholesterolaemia, which causes very high cholesterol from a young age regardless of lifestyle. Certain other conditions, such as an underactive thyroid, kidney or liver disease and poorly controlled diabetes, can raise cholesterol too.

High cholesterol is found with a blood test that measures the different types of cholesterol and other blood fats. The result usually reports total cholesterol, LDL or non-HDL ("bad") cholesterol, HDL ("good") cholesterol and triglycerides. Some tests can be done without fasting, while others ask you not to eat beforehand.

Your cholesterol numbers are usually considered alongside other factors, such as blood pressure, weight, smoking, diabetes and family history, to estimate your overall risk of heart and circulatory disease. This combined picture helps guide whether lifestyle changes alone or additional treatment are recommended.

The first step is usually changing the habits that affect cholesterol. This includes eating less saturated fat and more fibre, vegetables and fruit, being more physically active, reaching a healthy weight, cutting down on alcohol and stopping smoking. These changes can lower cholesterol and improve heart health more broadly.

When lifestyle changes are not enough, or when overall risk is high, medicines are added. Statins are the most commonly used and work by reducing the amount of cholesterol the liver makes; other medicines may be used in addition or as alternatives. Cholesterol is then rechecked to see how well treatment is working.

A heart-healthy lifestyle helps keep cholesterol in a healthy range: a balanced diet low in saturated fat, regular physical activity, a healthy weight, limited alcohol and not smoking. Having your cholesterol checked when advised means any problem can be picked up early.

Lowering raised cholesterol reduces the long-term risk of heart attack, stroke and other vascular disease. Because cholesterol can creep back up if habits or treatment change, ongoing healthy living and regular review help keep the benefit over time.