High Cholesterol
Symptoms, Causes & Treatment
Everything you need to know about high cholesterol: what it is, what causes it, why it matters, and the lifestyle changes and medications that effectively reduce your cardiovascular risk.
What Is High Cholesterol?
High cholesterol, or hyperlipidaemia, is a condition in which the level of cholesterol or other lipids (fats) in the blood is higher than is healthy. Like high blood pressure, high cholesterol is one of the most important modifiable risk factors for cardiovascular disease -- including heart attack and stroke -- and yet it causes no symptoms in itself, meaning millions of people are affected without knowing it.
Cholesterol is a waxy, fat-like substance that is essential to normal body function. It is used to build cell membranes, produce hormones (including oestrogen, testosterone, and cortisol), and synthesise vitamin D. The body produces all the cholesterol it needs in the liver; additional cholesterol comes from the diet.
Cholesterol is transported in the blood by lipoproteins:
- LDL cholesterol (low-density lipoprotein) -- often called "bad" cholesterol. High levels promote the deposit of cholesterol in artery walls, forming atherosclerotic plaques that narrow and stiffen the arteries.
- HDL cholesterol (high-density lipoprotein) -- often called "good" cholesterol. HDL transports cholesterol away from artery walls back to the liver for disposal, and is protective against cardiovascular disease.
- Triglycerides -- another type of blood fat, elevated levels of which are associated with increased cardiovascular risk, particularly alongside high LDL and low HDL.
- Total cholesterol -- the sum of all cholesterol fractions.
In the UK, approximately six out of ten adults have a total cholesterol level above the recommended threshold. Cardiovascular disease remains the leading cause of death in the UK, and high cholesterol is one of its most preventable drivers.
Does High Cholesterol Have Symptoms?
High cholesterol itself causes no symptoms — it is a silent condition identified only by blood testing. In rare cases of very high cholesterol (particularly familial hypercholesterolaemia), physical signs may appear.
High cholesterol has no symptoms — it is detected only through a blood test · Xanthelasma (yellow deposits around the eyes) may suggest high lipids · Xanthomata (fatty deposits on tendons or skin) in familial hypercholesterolaemia · Early corneal arcus (grey ring around the iris) in younger people
Chest pain, breathlessness, or jaw pain on exertion (angina — a complication of untreated high cholesterol) · Sudden weakness, speech difficulty, or facial droop (stroke — emergency) · Crushing chest pain at rest (heart attack — call 999 immediately)
High cholesterol itself is not an emergency — but its complications are. Call 999 immediately if you have sudden crushing chest pain, sudden weakness or speech difficulty, or sudden vision loss. These may be signs of heart attack or stroke caused by years of uncontrolled high cholesterol.
What Causes High Cholesterol?
High cholesterol results from a combination of lifestyle factors, genetics, and underlying medical conditions. Understanding the cause helps determine the most appropriate treatment approach.
Saturated fats from red meat, dairy, and processed foods raise LDL cholesterol. Replacing them with unsaturated fats reduces LDL and improves the LDL:HDL ratio.
Familial hypercholesterolaemia (FH) is an inherited condition causing very high LDL from birth. It affects 1 in 250 people and significantly increases early cardiovascular risk if untreated.
Physical inactivity lowers HDL ('good') cholesterol. Regular aerobic exercise raises HDL and modestly lowers LDL and triglycerides.
Hypothyroidism, type 2 diabetes, chronic kidney disease, and liver disease can all raise cholesterol. Treating the underlying condition often improves lipid levels.
The combined oral contraceptive pill, corticosteroids, retinoids, and some antihypertensives can raise cholesterol or triglycerides as a side effect.
LDL particles infiltrate the arterial wall where they become oxidised, triggering an inflammatory cascade that leads to atherosclerotic plaque formation — narrowing arteries and increasing heart attack and stroke risk.
Key Risk Factors
How Is High Cholesterol Diagnosed?
A fasting lipid profile blood test measures total cholesterol, LDL, HDL, non-HDL cholesterol, and triglycerides. This is used alongside a QRISK3 cardiovascular risk assessment to determine whether treatment is needed. The QRISK3 score calculates your 10-year risk of heart attack or stroke based on your complete risk profile.
How Is High Cholesterol Treated?
Treatment depends on cholesterol levels, QRISK3 score, and whether any cardiovascular disease or familial hypercholesterolaemia is present. Lifestyle modification is first-line for most people; statins are recommended when QRISK3 exceeds 10% or in high-risk groups.
Supportive Measures
Dietary changes — reducing saturated fat and increasing soluble fibre — are the foundation of cholesterol management. Plant sterols and stanols (found in fortified foods) can lower LDL by a further 10–15%. Stopping smoking raises HDL and reduces overall cardiovascular risk independently of cholesterol levels. Statins should be taken consistently at the same time each day, ideally in the evening for most except atorvastatin.
If Cholesterol Remains High on Treatment
If LDL remains above target despite high-intensity statin therapy, ezetimibe should be added. For people with FH or very high cardiovascular risk not responding to statins plus ezetimibe, PCSK9 inhibitors (injectable agents such as evolocumab or alirocumab) can reduce LDL by a further 50–60% and are available via specialist referral. Bempedoic acid is a newer oral option for statin-intolerant patients.
When Should You Seek Medical Advice?
You develop sudden crushing chest pain, sudden weakness or speech difficulty, or sudden severe headache with visual loss — these may be signs of heart attack or stroke as a complication of longstanding high cholesterol.
You have never had your cholesterol checked and have risk factors (family history, diabetes, obesity) · You have been told your cholesterol is high but have not been offered treatment or lifestyle advice · You are on a statin and experiencing muscle pain · A close relative has been diagnosed with familial hypercholesterolaemia.
How Can You Lower Your Cholesterol?
Lifestyle changes are both prevention and treatment for high cholesterol. They are most effective when applied consistently alongside any prescribed medication.
Replace saturated fats with unsaturated fats (olive oil, nuts, oily fish). Increase soluble fibre (oats, pulses, fruit). Reduce processed and red meat. These changes can lower LDL by 10–20%.
At least 150 minutes of moderate aerobic exercise weekly raises HDL and lowers triglycerides. Even modest increases in physical activity produce meaningful lipid improvements.
A QRISK3 score of 10% or more over 10 years is the NICE threshold for offering statin therapy. Know your score — it uses your full cardiovascular risk profile, not cholesterol alone.
Reduce dietary saturated fat and replace with unsaturated fats (olive oil, oily fish, nuts). Increase soluble fibre from oats, pulses, and fruit. Plant stanols/sterols reduce LDL by 10–15%.
Smoking cessation raises HDL by 5–10% within weeks and removes one of the most powerful accelerators of atherosclerosis. Combination of statin and smoking cessation produces additive risk reduction.
Statins significantly reduce the risk of heart attack and stroke in high-risk individuals regardless of baseline cholesterol. They are safe, well-tolerated, and should not be discontinued without clinical advice.
Speak to a Clinician About High Cholesterol
Through The GP Service, you can speak to a licensed clinician, discuss your cholesterol results, get a QRISK3 assessment, and — where appropriate — receive a statin prescription or referral, all without a waiting room.
Expert clinical advice, when you need it.
High Cholesterol FAQs
NICE recommends offering a statin to people with a QRISK3 10-year cardiovascular risk of 10% or more. This uses your age, sex, blood pressure, cholesterol, diabetes status, ethnicity, deprivation, and family history. High-intensity statins (atorvastatin 20–80mg) are used for primary prevention in those with a QRISK3 ≥10%. For people with FH or established cardiovascular disease, statins are recommended regardless of QRISK3 score. A cholesterol level alone is not sufficient to determine whether treatment is needed.
Muscle aches are the most commonly reported side effect of statins, occurring in around 5–10% of people. Serious muscle damage (rhabdomyolysis) is rare. If you experience muscle pain or weakness, speak to your clinician — switching to a different statin or reducing the dose often resolves the problem. Do not stop statins abruptly without medical advice. Liver enzyme rises are usually mild and transient. Statins are not associated with meaningful cognitive impairment despite common concern.
LDL cholesterol is the most important target for treatment because it directly causes atherosclerotic plaque formation. However, triglycerides — elevated by excess refined carbohydrate and alcohol intake — independently increase cardiovascular risk, particularly when above 10 mmol/L (pancreatitis risk). Non-HDL cholesterol (which includes all atherogenic particles) is now preferred over LDL alone as a treatment target because it captures remnant particles and is more accurate in patients with diabetes. HDL cholesterol cannot currently be directly raised with medication, though exercise and smoking cessation both increase it.
Familial hypercholesterolaemia (FH) affects 1 in 250 people in the UK and causes very high LDL cholesterol from birth due to a genetic mutation. It is severely underdiagnosed — only 8% of those with FH in the UK have been identified. Diagnostic clues include very high total cholesterol (above 7.5 mmol/L in adults), a family history of early heart attack (under 60 in a first-degree relative), physical signs (xanthelasma, corneal arcus), or a personal history of early cardiovascular disease. DNA testing can confirm the mutation. Treatment is high-intensity statins from diagnosis, with PCSK9 inhibitors if needed.
The most common causes of bilateral ankle swelling are venous insufficiency (varicose veins and poor venous return), medications (particularly calcium channel blockers such as amlodipine), and inactivity. Heart failure is an important cause that must be excluded, particularly if accompanied by breathlessness. Bilateral swelling is rarely DVT — DVT almost always affects one leg at a time. If both ankles swell consistently at the end of the day and improve overnight, venous insufficiency and medication side effects are the most likely explanations.
Post-thrombotic syndrome (PTS) is a complication affecting 20–50% of people after DVT, causing chronic pain, swelling, skin changes, and — in severe cases — venous ulceration in the affected leg. It results from valve damage in the deep veins caused by the clot. The most effective prevention is wearing correctly fitted class 2 graduated compression stockings for at least 2 years after DVT. Early ambulation after DVT (walking is safe and beneficial), adequate anticoagulation, and compression therapy all reduce the risk. Severe PTS may require specialist vascular assessment.
Yes. Left ventricular hypertrophy (LVH) — thickening of the heart wall due to the increased work of pumping against high blood pressure — is a significant hypertension complication detectable on ECG or echocardiogram. Target organ damage from hypertension also affects the kidneys (hypertensive nephropathy — microalbuminuria, reduced eGFR), eyes (hypertensive retinopathy), and brain (white matter changes, lacunar infarcts). Checking for target organ damage at diagnosis and monitoring annually ensures appropriate treatment intensity.
Yes. Hypertension in pregnancy — particularly pre-eclampsia (hypertension with proteinuria after 20 weeks) — is a serious condition affecting 2–5% of pregnancies. It can cause maternal complications (seizures, stroke, organ failure) and fetal growth restriction or preterm birth. Safe antihypertensives in pregnancy include labetalol, nifedipine, and methyldopa. ACE inhibitors and ARBs must be avoided in pregnancy due to fetal toxicity. Women with pre-existing hypertension should have their medication reviewed before or at the start of pregnancy.