Preventing Heart Disease Before Symptoms Start: A Guide for Healthy Adults

Most heart attacks happen to people who felt well the day before. Coronary artery disease usually develops silently over years, so the most valuable moment to act is often before there are any symptoms at all. This is called primary prevention: reducing the risk of a first cardiovascular event.

This guide is for adults who have no diagnosed heart disease and no current symptoms. If you have chest pain, breathlessness or other concerning symptoms, that is a different situation and needs assessment now. See our guide on understanding chest pain.

Why act before symptoms appear

Atherosclerosis, the build-up of fatty plaque in artery walls, begins long before it narrows an artery enough to cause symptoms. For many people the first sign of the disease is a heart attack. Waiting for symptoms means waiting until the disease is already established.

Prevention works because the main drivers of risk build up gradually and many of them can be changed. Lowering them earlier, and keeping them lower for longer, reduces cumulative exposure and lowers lifetime risk.

Start by understanding your risk

Cardiovascular risk is not a single number. It reflects a combination of factors, some you cannot change and some you can.

Factors you cannot change include:

• your age and sex
• your family history, particularly a parent or sibling who developed heart disease or had a stroke at a young age
• some inherited conditions, such as familial hypercholesterolaemia or a raised lipoprotein(a)

Factors you can influence include:

• blood pressure
• cholesterol, and in particular the atherogenic particles carried by LDL and other lipoproteins
• whether you smoke
• blood sugar and diabetes
• weight, and especially waist circumference
• physical activity, diet, sleep and alcohol

No single factor tells the whole story. Two people with the same cholesterol can carry very different overall risk depending on the company that number keeps.

How clinicians estimate your risk

For most healthy adults, a clinician combines these factors into an overall estimate using a validated risk calculator. The estimate helps decide whether lifestyle change alone is reasonable or whether medication, usually a statin, is likely to help.

Different systems use different tools:

• In the UK, NICE recommends the QRISK3 calculator for adults aged 25 to 84 without existing cardiovascular disease. It estimates the chance of a heart attack or stroke over the next ten years. NICE advises offering a statin (atorvastatin 20 mg) for primary prevention when that ten-year risk is 10% or more, and it can also be considered below 10% for people who prefer it or whose risk may be underestimated.
• Across Europe and Ireland, the European Society of Cardiology uses SCORE2 for people aged 40 to 69 and SCORE2-OP for those aged 70 to 89. These estimate the ten-year risk of fatal and non-fatal cardiovascular events. What counts as high risk rises with age, so the same percentage means different things at 45 and at 75.

In Ireland, where these European tools are commonly used, the QRISK3 calculator is also sometimes applied.

The exact tool and threshold that apply to you depend on your age and profile, so ask your GP or cardiologist what your estimated risk is and what it means for your options.

Some people do not need a calculator because they are already known to be at high risk, and are offered treatment on that basis. These include people with chronic kidney disease, many people with type 1 diabetes, and people with familial hypercholesterolaemia.

Know your numbers

A few measurements form the foundation of prevention. It is worth knowing yours and what target applies to you.

• Blood pressure. Raised blood pressure often causes no symptoms yet is a major driver of heart attack and stroke. Our guide on what your blood pressure numbers mean explains the readings and the thresholds.
• Cholesterol and lipids. A standard lipid panel is a starting point, and in selected people ApoB or lipoprotein(a) add useful information. Our guide on decoding your cholesterol result walks through each line and gives the targets in both UK and US units.
• Blood sugar. Diabetes and pre-diabetes raise cardiovascular risk, so blood glucose or HbA1c is part of the picture for many people.

When inherited risk is higher

Two inherited patterns deserve particular attention because a standard risk calculator can miss them.

Familial hypercholesterolaemia (FH) is a common inherited condition that causes a high LDL cholesterol from early life and a high risk of premature heart disease. It should be suspected when total cholesterol is very high, above about 7.5 mmol/L (around 290 mg/dL), especially alongside a personal or family history of heart disease before the age of 60. Standard risk tools such as QRISK3 are not used in FH, because the lifetime risk is already high. FH needs proper assessment, often in a specialist lipid service, and affects relatives too.

Lipoprotein(a), or Lp(a), is an inherited, largely fixed level that raises the risk of both atherosclerosis and narrowing of the aortic valve. European and international guidance suggests measuring it at least once in a lifetime. A very high level, above about 180 mg/dL (roughly 430 nmol/L), carries a lifetime risk comparable to familial hypercholesterolaemia. Our cholesterol guide explains Lp(a) in more detail.

Tests that can refine risk in selected people

For most healthy adults, risk factors and a validated risk estimate are enough to guide prevention. In some people, an extra test sharpens the assessment when the decision is genuinely uncertain.

• Lipoprotein(a), as above, usually measured once, and particularly worthwhile when heart disease runs in the family.
• A coronary artery calcium (CAC) scan. This is a quick CT scan that measures calcified plaque in the heart arteries. Guidelines suggest it can help when someone is at borderline or intermediate calculated risk and it is unclear whether to start a statin. A score of zero indicates a low short-to-medium-term risk and can support deferring statin treatment and reassessing in a few years, provided there are no higher-risk features such as diabetes, current smoking or a strong family history of premature disease. A higher score argues for more determined prevention.

Whether any of these tests is appropriate depends on your history and should be discussed with your clinician. They refine a decision rather than serve as routine screening for everyone.

What makes the biggest difference

The everyday habits that lower cardiovascular risk are well established and reinforce one another.

• Do not smoke, and avoid vaping and second-hand smoke. Smoking is the leading preventable cause of cardiovascular disease, and stopping is one of the most powerful things you can do for your heart. Second-hand smoke also carries real risk.
• Move regularly. UK and international guidance recommends at least 150 minutes of moderate activity a week, or 75 minutes of vigorous activity, plus muscle-strengthening activity on at least two days. Activity benefits blood pressure, blood sugar, weight and mood.
• Eat a heart-healthy pattern. A diet rich in vegetables, fruit, wholegrains, legumes, nuts, fish and olive oil, with less ultra-processed food, refined sugar and excess salt, supports the numbers above.
• Keep a healthy weight and waist. Central weight in particular is linked to insulin resistance and cardiovascular risk.
• Sleep and stress. Poor sleep and chronic stress influence blood pressure and metabolic health, so they are part of prevention rather than separate from it.
• Alcohol. If you do not drink, there is no cardiovascular reason to start. If you do, follow current low-risk guidance.

These are the foundations of the Heart Reset approach, and they matter whether or not you also need medication.

What about a daily aspirin?

For many years a daily aspirin was widely taken to prevent a first heart attack. That advice has changed. In people without established cardiovascular disease, routine aspirin is no longer recommended, because the reduction in cardiovascular events is offset by a higher risk of serious bleeding.

NICE advises against routinely offering aspirin for primary prevention. In the United States, the USPSTF recommends against starting aspirin for prevention at age 60 or over, and treats it as an individual decision for people aged 40 to 59 who are at higher cardiovascular risk. Aspirin may still be discussed in a minority of higher-risk people who are not prone to bleeding.

This is about primary prevention only. If you already take aspirin because you have known heart disease, have had a stent or a heart attack, that is secondary prevention and the balance is different. Do not start or stop aspirin without medical advice.

When medication is added

For some people, lifestyle change is enough. For others, the estimated risk or a specific factor, such as a very high cholesterol or blood pressure, means that medication meaningfully lowers the chance of a first event. A statin is the usual first medicine, and the decision is shared, based on overall risk rather than a single number in isolation.

Medication does not replace the habits above. It works alongside them.

What you can do this month

1. Book a check of your blood pressure, cholesterol and blood sugar if you do not know your current numbers.
2. Write down your family history, including any heart attack or stroke in a parent or sibling and the age it happened.
3. Ask your clinician for an estimate of your cardiovascular risk and what it means for you.
4. Choose one habit to build on this month, and make it sustainable rather than dramatic.

Prevention is rarely about a single decision. It is the steady effect of the right numbers, held in the right range, for years.

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Medical note: This article provides general education and is not an individual assessment. Decisions about cardiovascular risk, testing and any medication require a personal assessment with your GP or cardiologist. Do not start or stop any medicine, including aspirin or a statin, without advice.

Sources

• NICE NG238: Cardiovascular disease risk assessment and lipid modification
• NICE CG71: Familial hypercholesterolaemia
• 2021 ESC Guidelines on cardiovascular disease prevention in clinical practice
• ESC SCORE2 and SCORE2-OP risk charts
• 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease
• USPSTF 2022: Aspirin use to prevent cardiovascular disease
• NHS: Physical activity guidelines for adults aged 19 to 64
• British Heart Foundation: Risk factors