Statins are medicines used to reduce the risk of heart attacks and strokes. They are usually offered when someone's overall cardiovascular risk is high enough that lowering cholesterol is likely to make a meaningful difference.
Quick Answer
A statin lowers LDL cholesterol, sometimes called "bad cholesterol". Lower LDL over time means less cholesterol building up in blood vessels, which reduces the chance of heart attacks and strokes.
The benefit is bigger for people at higher starting risk. Lifestyle changes still matter: they reduce risk in many different ways and work hand in hand with medication.
Why Might I Be Offered A Statin?
Your clinician may discuss a statin if you have already had a heart attack or stroke, have certain conditions such as diabetes or chronic kidney disease, or if your calculated cardiovascular risk is raised.
In UK practice, this is often discussed using a risk calculator such as QRISK. It estimates your chance of having a heart attack or stroke over the next 10 years.
A statin is not usually offered because of one cholesterol number alone. It is about your whole risk picture: age, blood pressure, smoking, diabetes, kidney disease, family history, cholesterol levels and other factors.
How Do Statins Work?
Statins reduce how much cholesterol your liver makes. This lowers LDL cholesterol in the blood.
Over time, lower LDL reduces the amount of cholesterol entering artery walls. That lowers the chance of fatty plaques causing heart attacks or strokes.
When And How Should I Take It?
Most statins are taken once a day. Many people are advised to take their statin in the evening, because the body makes more cholesterol overnight. The best time still depends on the statin you are prescribed, so follow the instructions on your label.
- Atorvastatin can usually be taken at any time of day, but taking it in the evening is also fine if that helps you remember.
- Some statins, such as simvastatin, are often taken in the evening.
- If you forget a dose, check the patient leaflet or ask a pharmacist. Do not double up unless you have been specifically told to.
Statins work best when taken regularly. They are usually a long-term prevention medicine rather than a tablet you feel working straight away.
What Does The Benefit Look Like?
Number needed to treat, or NNT, can sound confusing. A simpler way is to imagine 100 people with the same risk as you.
If 100 people have a 10% risk
About 10 people may have a heart attack or stroke over 10 years.
About 7 or 8 people may have a heart attack or stroke.
About 2 or 3 people avoid one.
Another way to say this: about 40 people take a statin for 10 years to prevent one heart attack or stroke.
If 100 people have a 20% risk
About 20 people may have a heart attack or stroke over 10 years.
About 15 people may have a heart attack or stroke.
About 5 people avoid one.
Another way to say this: about 20 people take a statin for 10 years to prevent one heart attack or stroke.
These are simplified examples. Your personal benefit depends on your risk factors, the statin dose, how much your LDL falls and how long you take it for.
What About Side Effects?
Most people take statins without major problems. Some people report muscle aches, digestive symptoms, headache or tiredness. Serious side effects are uncommon, but they can happen.
Important symptoms to report include severe muscle pain or weakness, dark urine, yellowing of the skin or eyes, or symptoms that feel worrying or unusual for you.
The Placebo And Nocebo Effect
Side effects are real symptoms. The question is whether the statin is always the cause.
In the SAMSON trial, people who had stopped statins because of side effects took statin tablets, placebo tablets and no-tablet months in a random order. Symptom scores were much higher in both tablet months than in no-tablet months, and the researchers estimated that most of the symptom burden triggered by taking a tablet was also seen with placebo.
The StatinWISE trial also found no overall difference in muscle symptoms between atorvastatin and placebo periods in people who had previously reported muscle symptoms on statins.
This is often called the nocebo effect: symptoms can be triggered or amplified by expectation, worry or normal background aches and pains.
This does not mean symptoms are imagined. It means that stopping a statin permanently may not always be the best first step. Sometimes a careful pause, rechallenge, lower dose or different statin can help work out what is really going on.
Statins And Lifestyle: Not Either/Or
Lifestyle measures reduce cardiovascular risk in ways a statin cannot. Statins lower LDL cholesterol, but lifestyle can also improve blood pressure, insulin resistance, weight, fitness, inflammation, stress and overall wellbeing.
Statins help by
- Lowering LDL cholesterol
- Reducing heart attack risk
- Reducing stroke risk
- Working quietly in the background
Lifestyle helps by
- Improving blood pressure
- Supporting weight and glucose control
- Improving fitness and mood
- Reducing risk across many body systems
The best answer is often both: medication where the benefit is worthwhile, alongside lifestyle changes that support the whole person.
Five Things To Remember
- Statins reduce the risk of heart attacks and strokes by lowering LDL cholesterol.
- The benefit depends on your starting cardiovascular risk.
- Most people tolerate statins well, but side effects should be taken seriously and reviewed thoughtfully.
- Many symptoms blamed on statins also occur on placebo, so a careful review can prevent stopping a helpful medicine unnecessarily.
- Lifestyle measures and statins work hand in hand.
Dr Mel's Notebook
Did you know?
Two people can have the same cholesterol number but get different advice. That is because the decision is based on their whole heart and stroke risk, not cholesterol alone.
Try this today
Look at your cardiovascular risk using the QRISK3 calculator, then discuss the result with your GP, nurse or pharmacist.
The evidence
NICE recommends discussing atorvastatin for primary prevention when 10-year cardiovascular risk is 10% or more, alongside lifestyle advice and shared decision making.
Useful Sources
NICE NG238: Cardiovascular disease risk assessment and lipid modification
SAMSON trial correspondence: statin side effects and nocebo effect
Last updated: 9 July 2026