Heart Health: The Complete Guide

Key numbers at a glance

How your heart and blood vessels work

Your heart is a muscular pump about the size of a fist. Its right side receives blood returning from the body and sends it to the lungs to pick up oxygen; its left side pumps that oxygen-rich blood out through the arteries to every organ. Valves keep blood flowing in one direction, and the heart muscle itself is supplied by its own network of coronary arteries running over its surface. When people talk about heart disease, they most often mean disease of those coronary arteries.

Heart disease is the leading cause of death in the US for men and for women. Yet much of it develops silently over decades, driven by factors such as blood pressure, cholesterol, blood sugar and smoking that cause no symptoms until damage has been done. That is the central message of this guide: you cannot rely on feeling well, but you can find out your numbers, and the measures that lower risk are among the most effective tools in medicine.

How arteries become narrowed

Atherosclerosis is the slow build-up of fatty plaque in the walls of arteries. LDL cholesterol carries fat into the artery wall, and high blood pressure, smoking and high blood sugar damage the lining and speed the process. Plaque can narrow an artery enough to cause chest pain on exertion, called angina. More dangerously, a plaque can rupture, triggering a blood clot that suddenly blocks the artery. In the heart, that is a heart attack; in an artery supplying the brain, it can cause a stroke. The same process affects arteries in the legs, kidneys and elsewhere.

The heart's electrical system

Each heartbeat is triggered by an electrical signal that starts in a natural pacemaker in the upper chamber and spreads in an orderly way through the heart. Problems with this system cause arrhythmias. The most common sustained one is atrial fibrillation (AFib), in which the upper chambers quiver irregularly. AFib can cause palpitations, breathlessness and fatigue, or no symptoms at all, and it substantially raises the risk of stroke because clots can form in the poorly emptying chamber. Treatment to prevent clots greatly reduces that risk once AFib is found.

What raises your risk

Some risk factors cannot be changed. Risk rises with age, and men tend to develop heart disease earlier than women, although it remains the leading cause of death in women too. A family history matters, particularly a father or brother diagnosed with heart disease before 55, or a mother or sister before 65. Some inherited conditions, such as familial hypercholesterolemia, cause very high LDL cholesterol from birth and are much more common than most people realize; if several relatives had heart attacks young, tell your doctor.

The risk factors you can change account for most heart disease. High blood pressure, high LDL cholesterol, diabetes, smoking, physical inactivity, excess weight, an unhealthy diet and poor sleep each raise risk, and they multiply rather than simply add together. Someone with moderately raised blood pressure who also smokes and has diabetes is at far higher risk than any one factor would suggest. That is why US guidelines base decisions on your overall risk rather than on a single number.

Other conditions are linked to higher risk as well: chronic kidney disease, autoimmune conditions such as rheumatoid arthritis and lupus, and complications during pregnancy such as preeclampsia, gestational diabetes and high blood pressure in pregnancy. These are easy to forget years later, so make sure they are in your medical record. Long-term stress, depression and social isolation are also associated with heart disease, partly through their effects on sleep, eating, activity and smoking.

Blood pressure

Blood pressure is the force of blood against artery walls, written as two numbers in millimeters of mercury (mm Hg). The top number, systolic, is the pressure while the heart beats; the bottom number, diastolic, is the pressure between beats. High blood pressure almost never causes symptoms, yet it is one of the largest modifiable risk factors for stroke, heart attack, heart failure, kidney disease and dementia. Many people who have it do not know.

The US Preventive Services Task Force recommends screening all adults 18 and older. Checking at least once a year is advised from age 40, or earlier if you are at higher risk; every 3-5 years is reasonable from 18 to 39 if previous readings were normal. A diagnosis should be confirmed with readings outside the clinic, because some people's pressure rises only in the doctor's office, while others have normal clinic readings but high pressure the rest of the day.

Home monitoring makes this possible. Use a validated upper-arm cuff that fits your arm rather than a wrist device. Avoid caffeine, exercise and smoking for 30 minutes beforehand, empty your bladder, then sit quietly for 5 minutes with your back supported, feet flat and arm resting at heart level. Take two or three readings a minute apart and record them all. Bring the log, or the monitor itself, to your next appointment.

• Normal: below 120/80 mm Hg
• Elevated: 120-129 systolic and below 80 diastolic
• Stage 1 hypertension: 130-139 systolic or 80-89 diastolic
• Stage 2 hypertension: 140/90 mm Hg or higher
• Severe range: above 180/120 mm Hg; wait a few minutes, measure again, and contact your doctor right away if it is still that high, or call 911 if you have symptoms

Cholesterol and blood sugar

Cholesterol travels in the blood inside particles called lipoproteins, and a standard lipid panel reports several fractions. LDL cholesterol is the main driver of plaque, and lower is better for arteries. HDL cholesterol helps carry cholesterol away, though raising HDL with medicines has not been shown to protect the heart. Triglycerides are another type of blood fat, often raised by excess weight, high alcohol intake, diabetes and diets high in refined carbohydrates. Fasting is usually not needed for a cholesterol test.

Commonly quoted reference levels are total cholesterol below 200 mg/dL, LDL below 100 mg/dL, and HDL of 40 mg/dL or higher in men and 50 mg/dL or higher in women. But total cholesterol alone says little, and two people with the same LDL can receive different advice because their overall risk differs. The American Heart Association advises that adults have cholesterol checked every 4-6 years from age 20 if risk is low, and more often if it is not. A very high LDL, especially with a family history of early heart disease, can point to an inherited cause that needs treatment early.

Blood sugar matters just as much. Type 2 diabetes damages blood vessels and substantially raises the risk of heart disease and stroke over time, and prediabetes is often a stage on the way. Your doctor can check with a fasting glucose or A1C blood test. Many of the habits that lower blood pressure and cholesterol, including activity, weight loss where needed, more fiber and fewer sugary drinks, also improve blood sugar.

Checking your overall risk

Rather than treating each number separately, US guidelines estimate your chance of a heart attack or stroke over the next ten years. Tools in use include the Pooled Cohort Equations, used in the ASCVD Risk Estimator, and the newer AHA PREVENT calculator. They combine age, sex, blood pressure, cholesterol, diabetes, smoking and, in some tools, kidney function and other measures. Ask your doctor for your ten-year risk estimate, not just your readings. Where the decision is uncertain, a coronary artery calcium scan may be used to refine the estimate.

That estimate guides treatment. The USPSTF recommends a statin for adults aged 40-75 who have at least one risk factor, such as high cholesterol, diabetes, high blood pressure or smoking, and a ten-year risk of 10 percent or more. For those at 7.5 to under 10 percent, a statin may be offered after a discussion of the benefits and harms. People with very high LDL, diabetes or established heart disease are generally treated according to their own guidance regardless of the calculator.

Aspirin advice has changed. The USPSTF recommends against starting daily low-dose aspirin to prevent a first heart attack or stroke at age 60 or older, because the bleeding risk outweighs the benefit, and for adults 40-59 with a ten-year risk of 10 percent or more the decision should be individual. Do not start aspirin on your own, and if you already take it after a heart attack, stroke or stent, do not stop without talking to your doctor.

Your risk estimate is not fixed. It changes as you age, and it falls when blood pressure, cholesterol or blood sugar improve or when you stop smoking. Recalculating it every few years, or after a major change such as starting treatment or quitting, helps you and your doctor see whether your plan is working. It is also a useful way to compare options: seeing how much a particular change could lower your ten-year risk can make the decision about a medicine or a lifestyle change much clearer.

Warning signs and emergencies

With a heart attack or stroke, minutes matter: the sooner blood flow is restored, the less heart muscle or brain is lost. Delay is the biggest avoidable cause of damage, and it usually comes from waiting to see whether symptoms pass, or not recognizing symptoms that do not match the textbook picture. Women, older adults and people with diabetes are more likely to have less typical symptoms. Always call 911 rather than driving yourself or being driven, because emergency crews can start treatment on the way and alert the hospital.

Heart attack

The classic sign is chest discomfort, often described as pressure, tightness, fullness or squeezing, that lasts more than a few minutes or goes away and comes back. Discomfort can spread to one or both arms, the neck, jaw, back or stomach. Shortness of breath, a cold sweat, nausea or lightheadedness may accompany it or occur without chest pain. Women are more likely than men to have shortness of breath, nausea or vomiting, and back or jaw pain. Call 911, sit down and stay calm. Chew an aspirin only if the 911 dispatcher advises it and you are not allergic.

Stroke

Use F.A.S.T.: Face drooping, Arm weakness, Speech difficulty, Time to call 911. Other sudden signs include numbness or weakness on one side of the body, confusion, trouble seeing in one or both eyes, trouble walking or loss of balance, and a sudden severe headache with no known cause. Note the time symptoms started, because it affects which treatments can be given. Symptoms that go away within minutes still need emergency assessment, as they can be a warning that a major stroke may follow.

Cardiac arrest

Cardiac arrest is different from a heart attack: the heart's rhythm fails and it stops pumping. The person collapses, does not respond and is not breathing normally. Call 911, start Hands-Only CPR by pushing hard and fast in the center of the chest, and use an automated external defibrillator (AED) as soon as one is available; it gives spoken instructions. Survival depends heavily on bystanders acting quickly, which is why learning CPR is one of the most useful things you can do for the people around you.

Everyday habits that protect your heart

If you smoke, stopping is the single most effective thing you can do for your heart. Cardiovascular risk begins to fall soon after you quit and keeps falling for years, at any age. Quit medicines combined with counseling work far better than willpower alone, and FDA-approved options include nicotine replacement, varenicline and bupropion. Call 1-800-QUIT-NOW (1-800-784-8669) for free support. Secondhand smoke also harms the heart, so a smoke-free home and car protect your family.

Eating patterns that protect the heart are rich in vegetables, fruit, whole grains, beans, nuts, fish and unsaturated oils, and limited in processed meats, sugary drinks and refined snacks. The Dietary Guidelines for Americans 2020-2025 advise keeping sodium under 2,300 mg a day and saturated fat under 10 percent of calories, and replacing saturated fat with unsaturated fat rather than with refined carbohydrates. Most sodium comes from packaged, processed and restaurant food rather than the salt shaker, so reading Nutrition Facts labels makes a real difference.

Aim for at least 150 minutes a week of moderate activity, such as brisk walking, plus muscle-strengthening activity on 2 days; any amount is better than none. The same Dietary Guidelines advise that adults who drink limit alcohol to 2 drinks a day or fewer for men and 1 or fewer for women, where a US standard drink contains 14 g of alcohol, and note that drinking less is better for health than drinking more. Alcohol raises blood pressure and is a common trigger for AFib, and red wine is not a heart medicine.

Sleep and stress belong on the list too. Adults need 7 or more hours of sleep a night, and loud snoring with pauses in breathing can signal sleep apnea, which is linked to high blood pressure and AFib. Reaching and keeping a healthy weight improves blood pressure, cholesterol and blood sugar, and even modest weight loss helps. Managing stress through activity, social connection and, where needed, professional support is good for the heart as well as the mind.

Treatment and care options

When lifestyle changes are not enough, medicines are highly effective. Statins lower LDL cholesterol by reducing its production in the liver and are among the most studied medicines in use. Muscle aches are the most reported side effect, but blinded trials suggest most of these are not caused by the statin itself; if you have symptoms, discuss a lower dose or a different statin rather than stopping. Several other cholesterol-lowering medicines are available for people who need further reduction or cannot take statins.

Blood pressure medicines come in several classes, including thiazide-type diuretics, ACE inhibitors, angiotensin receptor blockers and calcium channel blockers, and many people need two or more to reach their target. They work only while you take them, so do not stop because readings have improved. Blood thinners (anticoagulants) are used to prevent stroke in AFib and to treat clots; they raise bleeding risk, so get emergency care after a head injury or for bleeding that will not stop.

For blocked coronary arteries, procedures include angioplasty with stenting, in which a balloon opens the artery and a mesh tube holds it open, and bypass surgery, which routes blood around blockages using another blood vessel. Heart failure, in which the heart cannot pump efficiently enough, is treated with a combination of medicines that improve symptoms and survival, along with daily weighing to catch fluid build-up early. Avoid NSAIDs such as ibuprofen and naproxen unless your doctor approves, as they can worsen fluid retention and blood pressure.

After a heart attack, stent, bypass surgery, valve surgery or a diagnosis of stable heart failure, cardiac rehabilitation is recommended. It is a medically supervised program of exercise, education and counseling over several weeks, and it is linked to fewer hospital readmissions and better quality of life. Medicare and many private insurers cover it for eligible conditions, though copays may apply. Many people who are eligible never attend, so ask for the referral and ask about home-based or virtual options.

Heart health for specific groups

Heart disease does not look the same in everyone, and some groups need specific attention or advice that differs from the general guidance above. Some medicines and targets change, symptoms may present differently, and certain life stages, such as pregnancy, leave a lasting mark on future risk. If you belong to one of these groups, use the notes below as a starting point for a conversation with your own doctor rather than a substitute for it.

Women and pregnancy

Heart disease is the leading cause of death in women, but symptoms are more often atypical and are sometimes dismissed. Pregnancy is a natural stress test: preeclampsia, gestational hypertension and gestational diabetes are linked to higher heart disease risk later in life, so tell every future doctor about them. During pregnancy, report severe headache, vision changes, swelling of the face or hands, or upper abdominal pain promptly. Some heart medicines, including statins and certain blood pressure medicines, are not used in pregnancy, so talk to your doctor before trying to conceive.

Children and teens

Heart habits start early. Children benefit from daily active play, water instead of sugary drinks, plenty of fruit and vegetables, enough sleep, and a smoke-free and vape-free environment. The American Academy of Pediatrics recommends checking cholesterol in late childhood and again in late adolescence or young adulthood, and earlier if there is a strong family history, which helps identify inherited high cholesterol early, when treatment makes the most difference. Fainting during exercise or chest pain with exertion in a young person needs prompt medical assessment.

Older adults

Risk rises with age, but so does the benefit of treatment. Older adults are more likely to have AFib, heart failure and side effects from medicines, including dizziness and falls from blood pressure treatment. Bring all your medicines, including supplements, to appointments for review. Breathlessness, swollen ankles or fatigue should not be dismissed as just age. Staying active, including strength and balance exercises, helps protect independence and reduces fall risk. Treatment goals are usually individualized in later life, balancing the benefits of tighter blood pressure or cholesterol control against side effects, other conditions and what matters most to you.

People with diabetes or kidney disease

Diabetes and chronic kidney disease both raise heart disease risk substantially and can blunt the warning signs of a heart attack. Blood pressure and cholesterol targets are often tighter, and some diabetes medicines have been shown to protect the heart and kidneys. Ask your care team how your treatment plan addresses your heart as well as your blood sugar or kidney function.

Costs, coverage and checkups in the US

Under the Affordable Care Act, most private plans must cover preventive services that the USPSTF recommends with an A or B grade without a copay when you use an in-network provider. For heart health that includes blood pressure screening, statins for eligible adults, and tobacco cessation counseling and medicines. Ask your plan exactly what is covered, because follow-up tests and visits for a problem found at screening may carry costs.

If you have Medicare, the yearly Annual Wellness Visit is a chance to review your risk factors, and Medicare covers cardiovascular screening blood tests and cardiac rehabilitation for eligible conditions. Many statins and blood pressure medicines are available as low-cost generics; if cost is a barrier, tell your doctor or pharmacist, who can often suggest an equally effective lower-cost option. Free quitline support is available through 1-800-QUIT-NOW, and community health centers offer care on a sliding fee scale if you are uninsured.

Common myths and what the guidance says

Heart health attracts a lot of reassuring but mistaken beliefs. Most of them encourage people to wait: to assume that feeling fine means low risk, or that a symptom is not serious enough to call 911. The guidance consistently points the other way. Others come from older advice that has since changed, such as routine daily aspirin for everyone over a certain age. Here are the ones that come up most often, set against what current US guidance says.

• Myth: I would know if my blood pressure were high. Guidance: high blood pressure almost never causes symptoms; the only way to know is to measure it.
• Myth: heart disease is a man's problem. Guidance: it is the leading cause of death in women too, and symptoms can be less typical.
• Myth: I am too young to worry. Guidance: plaque builds over decades, and inherited high cholesterol can cause heart attacks at a young age.
• Myth: a normal weight means low risk. Guidance: blood pressure, cholesterol, blood sugar, smoking and family history matter at every weight.
• Myth: red wine is good for the heart. Guidance: drinking less is better for health than drinking more; no one should start drinking for their heart.
• Myth: once my numbers are normal, I can stop my medicine. Guidance: they are normal because of the medicine; stopping usually brings them back up.
• Myth: chest pain that comes and goes is not serious. Guidance: discomfort that goes away and returns is a reason to call 911.

Talking to your doctor and a 4-week plan

Before your next checkup, gather your family history, especially any heart attacks, strokes or sudden deaths in close relatives and their ages, along with a list of your medicines and supplements and a week of home blood pressure readings if you have a monitor. Useful questions include: what are my blood pressure, LDL and blood sugar results, and what should they be? What is my ten-year risk, and would a statin help me? Should I be screened for any inherited condition? Is cardiac rehabilitation right for me?

If you are prescribed a new medicine, ask what it is for, how long you will take it, what side effects to report and what to do if you miss a dose. If you have symptoms such as breathlessness on exertion, palpitations or ankle swelling, describe when they happen and how they have changed. Being specific helps your doctor decide what tests you need.

The 4-week plan below suits most adults who want to start protecting their heart. If you have heart disease or symptoms, agree on any change in activity with your care team first. Keep earlier steps going as you add new ones, and do not worry about doing everything perfectly: small, lasting changes to sodium, activity and smoking add up to meaningful reductions in risk over months and years, and each one makes the next easier.

• Week 1: book a checkup if you have not had one in the past year, and start home blood pressure readings if you have a monitor
• Week 2: read Nutrition Facts labels and swap your three highest-sodium foods; replace butter and fatty meats with unsaturated oils, fish or beans
• Week 3: walk briskly for 30 minutes on 5 days, or build toward it in shorter bouts; if you smoke, call 1-800-QUIT-NOW and set a quit date
• Week 4: take a Hands-Only CPR class or video course, review your drinking, and ask your doctor for your ten-year risk estimate

Every guide in this topic

• Blood Pressure: What the Evidence Actually Says
• Cholesterol: Sorting the Evidence From the Noise
• What the Guidance Really Says About Cardiovascular Risk
• Smoking and the Heart: What Published Guidance Supports
• The Evidence on Alcohol and the Heart, Without the Hype
• Atrial Fibrillation: What the Evidence Actually Says
• Heart Attack Symptoms: What the Evidence Actually Says
• The Evidence on Heart Failure, Without the Hype
• Cardiac Rehabilitation: What the Evidence Actually Says
• What the Guidance Really Says About Statins

Frequently asked questions

What is a healthy blood pressure?

For adults, normal blood pressure is below 120/80 mm Hg. Readings of 130-139 systolic or 80-89 diastolic are stage 1 hypertension, and 140/90 or higher is stage 2. A single reading is not enough to diagnose high blood pressure; your doctor will want repeated readings, ideally including some taken at home.

How often should I have my cholesterol checked?

The American Heart Association advises checking every 4-6 years from age 20 if your risk is low, and more often if you have risk factors, a family history of early heart disease or are on treatment. Fasting is usually not needed. Ask for your LDL figure and your ten-year risk estimate, not just total cholesterol.

What are the signs of a heart attack in women?

Women can have the classic chest pressure, but they are more likely than men to have shortness of breath, nausea or vomiting, and back or jaw pain, sometimes without obvious chest pain. Unusual fatigue or lightheadedness can also occur. If symptoms last more than a few minutes or come and go, call 911.

Should I take a daily aspirin?

Not on your own. The USPSTF recommends against starting daily aspirin to prevent a first heart attack or stroke at 60 or older because bleeding risks outweigh benefits, and for adults 40-59 at higher risk the decision is individual. If you take aspirin after a heart attack, stroke or stent, do not stop it without talking to your doctor.

Do I need a statin?

The USPSTF recommends a statin for adults aged 40-75 with at least one risk factor, such as high cholesterol, diabetes, high blood pressure or smoking, and a ten-year risk of 10 percent or more. People with very high LDL, diabetes or existing heart disease follow their own guidance. Ask your doctor to calculate your risk.

Can I lower my blood pressure without medicine?

Often, yes, at least partly. Cutting sodium to under 2,300 mg a day, being active for 150 minutes a week, losing excess weight, limiting alcohol and stopping smoking all lower blood pressure. Many people still need medicine to reach their target, and that is not a failure. Never stop prescribed medicine without advice.

What should I do if someone collapses?

If they do not respond and are not breathing normally, call 911 and start Hands-Only CPR: push hard and fast in the center of the chest. Send someone to find an automated external defibrillator (AED) and use it as soon as it arrives; it talks you through each step. Keep going until help takes over.

Is atrial fibrillation dangerous?

AFib itself is often not immediately life-threatening, but it substantially raises the risk of stroke, and it can weaken the heart over time if the rate stays fast. Many people have no symptoms. Treatment to prevent clots greatly reduces stroke risk, so see your doctor about a new irregular pulse or palpitations.

Is heart disease inherited?

Family history raises risk, especially if a father or brother had heart disease before 55 or a mother or sister before 65. Some people inherit very high cholesterol, called familial hypercholesterolemia, which needs early treatment. Tell your doctor about your family history; it can change when screening starts and how your risk is treated.

Is cardiac rehabilitation worth doing?

Yes. Cardiac rehabilitation after a heart attack, heart surgery, a stent or a diagnosis of stable heart failure is linked to fewer hospital readmissions and better quality of life. It combines supervised exercise with education and support. Medicare and many private plans cover it for eligible conditions, and home-based or virtual options may be available.

When to speak to a doctor

See your doctor if you have not had your blood pressure checked in the past year, if home readings are consistently 130/80 or higher, or if you notice new palpitations, an irregular pulse, breathlessness on exertion or ankle swelling. If a reading is above 180/120, rest a few minutes and measure again; if it is still that high, contact your doctor right away. Call 911 for chest pain or pressure lasting more than a few minutes, pain spreading to the arm, neck or jaw, sudden shortness of breath, fainting, or any sign of stroke such as face drooping, arm weakness or speech difficulty. Never drive yourself to the hospital.

Where this comes from

• American Heart Association — Understanding Blood Pressure Readings
• US Preventive Services Task Force — Hypertension in Adults: Screening
• National Heart, Lung, and Blood Institute — Blood Cholesterol
• American Heart Association — What Your Cholesterol Levels Mean
• US Preventive Services Task Force — Statin Use for the Primary Prevention of Cardiovascular Disease in Adults: Preventive Medication
• US Preventive Services Task Force — Aspirin Use to Prevent Cardiovascular Disease: Preventive Medication
• American Heart Association — Warning Signs of a Heart Attack
• American Stroke Association — Stroke Symptoms
• Dietary Guidelines for Americans — Dietary Guidelines for Americans, 2020-2025
• CDC — Benefits of Quitting Smoking

How this page was put together

Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarized or generalized beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.

Medical disclaimer

This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to your doctor, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 911.