Preventing Heart Attack and Stroke: The Complete Guide to Protecting Your Heart and Brain

Cardiovascular disease, mainly heart attacks and strokes, is the world’s leading cause of death, claiming around 20 million lives every year. More than three quarters of these deaths occur in low- and middle-income countries, and many happen in people under 70. Yet the World Health Organization estimates that the majority of premature heart attacks and strokes are preventable. The main causes are well known, measurable and changeable: high blood pressure, high cholesterol, diabetes, smoking, unhealthy diet, physical inactivity, excess weight and harmful alcohol use.

This guide explains how heart attacks and strokes happen, how to understand your own risk, the numbers you should know, the lifestyle changes and medicines that make the biggest difference, and the warning signs that need emergency action.

How heart attacks and strokes happen

Atherosclerosis: the common cause

Most heart attacks and many strokes are caused by atherosclerosis, a build-up of fatty deposits called plaque in the walls of arteries. Over years, plaque narrows arteries and makes them stiffer. High blood pressure, high LDL cholesterol, smoking, diabetes and inflammation all speed up this process. If a plaque cracks, a blood clot forms on it and can suddenly block the artery.

Heart attack

A heart attack (myocardial infarction) happens when a blood clot blocks an artery supplying the heart muscle. Without oxygen, the heart muscle begins to die. The faster the artery is reopened, the more heart muscle is saved.

Stroke

A stroke happens when blood supply to part of the brain is cut off. About 85 percent of strokes are ischaemic, caused by a clot blocking an artery to the brain, often from atherosclerosis or from a clot that travels from the heart, for example in atrial fibrillation. The rest are haemorrhagic, caused by bleeding in or around the brain, most often due to high blood pressure.

Transient ischaemic attack (TIA)

A TIA, or “mini-stroke”, causes stroke symptoms that resolve within minutes to hours. It is a warning sign: the risk of a full stroke is highest in the days after a TIA. Anyone with TIA symptoms should seek urgent medical assessment, even if they feel fine afterwards.

Know your risk

Your risk of a heart attack or stroke depends on a combination of factors. Some you cannot change:

• Age: risk rises as you get older
• Sex: men tend to develop heart disease earlier, but it is also the leading cause of death in women
• Family history: a parent or sibling with heart disease or stroke at a young age (under 55 in men, under 65 in women)
• Ethnicity: people of South Asian heritage have higher rates of heart disease; people of African and African-Caribbean heritage have higher rates of high blood pressure and stroke

Many others you can change:

• High blood pressure, the single biggest risk factor for stroke and a major one for heart attacks
• High LDL cholesterol
• Smoking and tobacco use, including shisha and chewing tobacco
• Diabetes
• Physical inactivity
• Unhealthy diet, especially high salt, high in processed foods and low in fruit and vegetables
• Obesity, especially around the waist
• Harmful alcohol use
• Kidney disease
• Air pollution
• Chronic stress, depression, poor sleep and social isolation

Risk calculators

Healthcare providers use risk calculators, such as the WHO cardiovascular risk charts, QRISK3 in the UK, SCORE2 in Europe and the PREVENT equations in the United States, to estimate your chance of a heart attack or stroke over the next 10 years. Your result helps decide whether medicines such as statins are recommended. Ask for a cardiovascular risk assessment if you are over 40, or earlier if you have risk factors.

The numbers to know

Blood pressure

Normal blood pressure is generally below 120/80 mmHg. High blood pressure is usually diagnosed at 140/90 or higher in many guidelines, or 130/80 in US and some European guidelines. Most people with high blood pressure have no symptoms, so the only way to know is to measure it. Adults should have their blood pressure checked at least every five years, and more often if it is borderline or high. Home blood pressure monitors are useful and widely available.

Cholesterol

LDL cholesterol (“bad” cholesterol) contributes to plaque build-up. HDL (“good” cholesterol) helps remove cholesterol. Targets depend on your overall risk; people who have already had a heart attack or stroke usually need much lower LDL levels. A one-off test of lipoprotein(a), a genetically determined type of cholesterol particle, is now recommended in some guidelines to identify people with inherited higher risk.

Blood sugar

An HbA1c test measures average blood sugar over two to three months. An HbA1c of 48 mmol/mol (6.5 percent) or above indicates diabetes, and 42 to 47 mmol/mol (6.0 to 6.4 percent) suggests a higher risk.

Waist and weight

A waist measurement more than half your height suggests increased risk.

Heart rhythm

Atrial fibrillation, an irregular heartbeat, increases the risk of stroke around five times. Checking your pulse for irregularity, particularly over 65, can help detect it. Anticoagulant medicines greatly reduce stroke risk in people with atrial fibrillation.

Lifestyle: the foundation of prevention

The American Heart Association’s “Life’s Essential 8” summarises the key factors for heart and brain health: eat better, be more active, quit tobacco, get healthy sleep, manage weight, control cholesterol, manage blood sugar and manage blood pressure.

Stop smoking

Smoking damages artery walls, raises blood pressure, makes blood more likely to clot and reduces oxygen in the blood. Smokers have around twice the risk of heart attack and stroke. Risk begins to fall within a year of stopping and continues to drop over time. Second-hand smoke also increases risk. Nicotine replacement therapy, varenicline, cytisine and behavioural support greatly increase the chances of quitting. E-cigarettes are less harmful than smoking but not risk-free, and are not recommended for non-smokers.

Eat for your heart

• Cut salt: WHO recommends less than 5 grams of salt (about one teaspoon) a day. Most salt comes from processed foods, bread, stock cubes, sauces and restaurant food. Lowering salt reduces blood pressure within weeks. Potassium-enriched salt substitutes have been shown to reduce stroke in people at high risk, but check with your healthcare provider if you have kidney disease or take certain medicines.
• Eat more fruit and vegetables: at least five portions a day.
• Choose whole grains, beans, lentils, nuts and seeds.
• Choose healthy fats: olive oil, rapeseed oil, nuts, avocado and oily fish, instead of butter, ghee, palm oil and fatty meat.
• Avoid trans fats, found in some fried foods, margarines and baked goods. Many countries have now banned industrial trans fats.
• Limit red and processed meat, such as sausages, bacon and processed deli meats.
• Cut sugary drinks and foods high in added sugar.
• Mediterranean and DASH-style diets have strong evidence for reducing heart disease and blood pressure.

Move more

Regular physical activity lowers blood pressure, improves cholesterol, helps control weight and blood sugar, and reduces the risk of heart disease and stroke by around 20 to 35 percent. Aim for at least 150 minutes of moderate activity, such as brisk walking, each week, plus muscle-strengthening on two days. Reduce sitting time. Every step counts: studies show benefits even at modest increases in daily steps.

Maintain a healthy weight

Losing even 5 to 10 percent of body weight improves blood pressure, cholesterol and blood sugar. In 2023, the SELECT trial showed that semaglutide reduced heart attacks, strokes and cardiovascular deaths by about 20 percent in people with obesity and existing heart disease, but without diabetes.

Limit alcohol

Heavy drinking raises blood pressure, causes irregular heart rhythms and increases the risk of stroke, especially haemorrhagic stroke. Recent evidence suggests that no level of drinking is beneficial for the heart overall. If you drink, keep it low and have alcohol-free days.

Sleep and stress

Aim for seven to nine hours of sleep. Untreated sleep apnoea raises blood pressure and stroke risk. Chronic stress, depression and loneliness are linked to heart disease; managing stress, staying connected and seeking help for mental health problems protect your heart too.

Medicines that prevent heart attacks and strokes

For people at high risk, medicines add significant protection on top of lifestyle changes.

Blood pressure medicines

Lowering blood pressure by 10 mmHg systolic reduces the risk of major cardiovascular events by about 20 percent and stroke by about 27 percent, according to a large analysis in The Lancet. Common medicines include ACE inhibitors (for example, lisinopril, ramipril), angiotensin receptor blockers (losartan, candesartan), calcium channel blockers (amlodipine) and thiazide-like diuretics (indapamide, chlorthalidone). Many people need two or more medicines, and single-pill combinations make treatment easier. WHO’s HEARTS package promotes simple, standardised treatment protocols to improve blood pressure control worldwide.

Statins

Statins, such as atorvastatin and rosuvastatin, lower LDL cholesterol and reduce heart attacks and strokes in people at increased risk. They are among the most studied medicines in the world. Most people tolerate them well. Muscle aches are often reported, but large blinded trials show that most muscle symptoms occur just as often with a placebo. Never stop a statin without discussing it first; there are alternatives and dose adjustments available. Other cholesterol-lowering medicines include ezetimibe, PCSK9 inhibitors and inclisiran for people at very high risk.

Aspirin

Low-dose aspirin is recommended for people who have already had a heart attack or ischaemic stroke, to prevent another. For people without existing heart disease, guidelines no longer recommend routine aspirin, because the risk of bleeding often outweighs the benefit. Do not start aspirin without advice.

Anticoagulants

People with atrial fibrillation are usually offered anticoagulants such as apixaban, rivaroxaban, edoxaban, dabigatran or warfarin, which reduce stroke risk by around two thirds.

Diabetes medicines

Some newer diabetes medicines, such as SGLT2 inhibitors (empagliflozin, dapagliflozin) and GLP-1 receptor agonists (semaglutide, liraglutide), reduce heart attacks, strokes, heart failure and kidney disease in people with type 2 diabetes and existing heart disease or high risk.

Taking medicines long term

Prevention medicines work only if taken regularly, usually for life. Many people stop because they feel well or worry about side effects. If you have concerns, talk to your nurse or pharmacist. A once-daily routine, pill organisers and combination pills help.

Warning signs: act fast

Heart attack symptoms

• Chest pain, pressure, tightness or heaviness, often in the centre of the chest, lasting more than a few minutes
• Pain spreading to the arms (especially the left), neck, jaw, back or stomach
• Shortness of breath
• Sweating, feeling sick or vomiting
• Light-headedness or a sense of dread

Women, older people and people with diabetes are more likely to have less typical symptoms, such as breathlessness, unusual tiredness, nausea or back or jaw pain, sometimes without obvious chest pain.

What to do

• Call emergency services immediately; do not drive yourself to hospital
• Sit down and rest
• If you are not allergic and have been advised it is safe, chew one 300-milligram aspirin while waiting, as emergency services advise
• If the person collapses and is not breathing normally, start CPR and use a defibrillator (AED) if available

Stroke symptoms: BE FAST

• Balance: sudden loss of balance or coordination
• Eyes: sudden loss of vision or double vision
• Face: one side of the face drooping
• Arms: weakness or numbness in one arm or leg
• Speech: slurred speech or difficulty understanding
• Time: call emergency services immediately and note the time symptoms began

Other symptoms include sudden severe headache, confusion and dizziness. Clot-busting drugs and clot-removal procedures (thrombectomy) can dramatically reduce disability, but only if given within hours. Every minute matters: during a stroke, around two million brain cells die each minute.

After a heart attack or stroke: preventing another

People who have had a heart attack or stroke are at high risk of another. Secondary prevention includes medicines (usually an antiplatelet, statin, blood pressure medicines and others), cardiac or stroke rehabilitation, stopping smoking, healthy eating, physical activity and regular follow-up. Cardiac rehabilitation programmes reduce deaths and hospital admissions, yet many eligible people do not attend. Ask for a referral.

Heart health for women

Heart disease is the leading cause of death in women worldwide, yet women are less likely to receive timely diagnosis and treatment. Conditions specific to women, such as pre-eclampsia, gestational diabetes, early menopause and polycystic ovary syndrome, increase long-term risk. If you have had any of these, tell your healthcare provider and have regular checks of blood pressure, cholesterol and blood sugar.

Heart health in young people

Heart disease is increasingly seen in younger adults, linked to rising obesity, diabetes, high blood pressure, smoking and vaping, and drug use such as cocaine. Habits formed in childhood and early adulthood shape lifelong risk. Familial hypercholesterolaemia, an inherited condition causing very high cholesterol from birth, affects around 1 in 250 people and is often undiagnosed. Testing family members of anyone with early heart disease or very high cholesterol is important.

Community and policy action

Individual choices matter, but so does the environment. Policies that reduce salt in processed foods, ban trans fats, tax tobacco and sugary drinks, create safe spaces for walking and cycling, reduce air pollution and make blood pressure and cholesterol treatment affordable save millions of lives. WHO estimates that scaling up blood pressure treatment alone could prevent around 76 million deaths between 2023 and 2050.

The nurse’s role

Nurses are at the heart of cardiovascular prevention. Practice and community nurses measure blood pressure, run health checks, calculate risk, support smoking cessation, manage hypertension and diabetes clinics, and help people take medicines. In many countries, nurse-led task-sharing models have significantly improved blood pressure control. Cardiac and stroke specialist nurses support people through emergency care, rehabilitation and long-term follow-up.

A heart-healthy week: putting it into practice

• Monday: measure your blood pressure at home or at a pharmacy and write it down. Swap your usual salty snack for fruit or unsalted nuts.
• Tuesday: take a 30-minute brisk walk. Check food labels for salt and choose lower-salt options.
• Wednesday: cook a meal with beans, lentils or oily fish and plenty of vegetables, using herbs and spices instead of stock cubes.
• Thursday: do some strength exercises at home, such as sit-to-stands and wall press-ups.
• Friday: have an alcohol-free evening and get to bed on time.
• Saturday: an active day out: dancing, cycling, gardening, playing with children or a long walk with friends.
• Sunday: plan meals for the week, set up your pill organiser if you take medicines, and reflect on what went well.

If you smoke, the most important single step is to set a quit date and get support. If you have not had your cholesterol, blood sugar or blood pressure checked recently, book those tests.

Understanding your blood pressure readings at home

Home readings are usually slightly lower than clinic readings, and many guidelines use 135/85 mmHg as the threshold for high blood pressure at home. For accurate results:

• Use a validated upper-arm monitor with the right cuff size
• Avoid caffeine, smoking and exercise for 30 minutes beforehand
• Sit quietly for five minutes with your back supported, feet flat and arm resting at heart level
• Take two readings a minute apart, morning and evening, for several days, and share the average with your nurse

Seek urgent help if your reading is very high (for example 180/120 or above) with symptoms such as chest pain, severe headache, breathlessness, confusion or vision changes.

Heart health and other conditions

Several long-term conditions significantly increase cardiovascular risk and mean prevention is even more important. These include chronic kidney disease, rheumatoid arthritis and other inflammatory conditions, HIV, severe mental illness, and a history of cancer treatment with certain chemotherapies or chest radiotherapy. If you live with any of these, ask your care team to include a cardiovascular risk assessment as part of your regular reviews.

Frequently asked questions

At what age should I start checking my heart health?

Blood pressure should be checked from adulthood. Formal cardiovascular risk assessment is usually recommended from 40, or earlier with risk factors or a family history.

Can you reverse heart disease?

Plaque can stabilise and sometimes shrink slightly with intensive cholesterol lowering and lifestyle changes. Risk of events can be greatly reduced.

Is chest pain always a heart attack?

No, but it should always be taken seriously. Call emergency services if chest pain is severe, lasts more than a few minutes, or comes with breathlessness, sweating or nausea.

Does stress cause heart attacks?

Chronic stress contributes to heart disease, and sudden intense emotional stress can trigger heart problems in some people.

Are eggs bad for my heart?

For most people, eating eggs in moderation as part of a healthy diet does not significantly raise heart disease risk.

But I feel fine. Why should I worry now?

Because high blood pressure, high cholesterol and early diabetes usually cause no symptoms until a heart attack or stroke happens. Feeling fine is not the same as being at low risk. A five-minute blood pressure check and a simple blood test can reveal a hidden danger, and acting early can add healthy years to your life.

Related: High blood pressure guide · How to lower cholesterol · Statins: benefits and myths · Heart attack signs in men and women

Sources: World Health Organization (cardiovascular diseases fact sheet; HEARTS technical package; Global report on hypertension 2023), World Heart Federation, American Heart Association (Life’s Essential 8), European Society of Cardiology prevention guidelines, The Lancet (Ettehad et al., blood pressure lowering meta-analysis), SELECT trial (New England Journal of Medicine, 2023).