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Smoking is the leading cause of preventable death in the world. According to the CDC, diseases caused by smoking kill more than 480,000 people in the U.S. each year. The CDC also states that smokers are 2 to 4 times more likely to develop heart disease and stroke. Despite the known dangers, many people continue to smoke or start smoking every year. One out of 5 deaths of Americans is related to smoking, and it kills more Americans each year than suicides, homicides, AIDS, and car accidents combined. According to the CDC, 9 in 10 new smokers are children and teens. In many cases, they are replacing the smokers who quit or died prematurely from a smoking-related disease.

Smokers not only have increased risk for lung disease, including lung cancer and emphysema, but also have increased risk for heart disease, stroke, and oral cancer. Almost one-third of all cancers are related to smoking. Smoking kills more women each year than breast cancer. Smoking also contributes to the development of diabetes, tuberculosis, immune system disease, and male impotence.

How does smoking affect the cardiovascular system?

In posing health risks on the body's cardiovascular system, smoking:

  • Causes immediate and long-term increases in blood pressure

  • Causes immediate and long-term increases in heart rate

  • Reduces cardiac output and coronary blood flow

  • Reduces the amount of oxygen that reaches the body's tissues


  • Contributes to an increased risk for blood clot formation

  • Damages blood vessels


Smoking has also been linked to depression and psychological distress.

What are the risks of secondhand smoke?


Both direct and indirect smoking exposure poses significant health hazards to pregnant women, infants, and young children. Children and babies exposed to tobacco smoke are more likely to have ear infections and asthma, and are at a higher risk for SIDS (sudden infant death syndrome) than children and babies without the same exposure.

These common symptoms may be linked to exposure to secondhand smoke:

  • Irritation of the eyes, nose, and throat

  • Coughing

  • Excessive mucus in the airways (phlegm)

  • Chest discomfort from lung irritation

  • Chest pain, which may mean heart disease

The symptoms of secondhand smoke exposure may look like other health conditions. Always see your healthcare provider for a diagnosis.


Smoking and cardiovascular disease

Smoking is one of the main risk factor for heart disease. Other risk factors are high cholesterol, high blood pressure, physical inactivity, obesity, and diabetes. In fact, smoking is the single most preventable cause of premature death in the U.S.

Importance of smoking cessation

Eliminating smoking has both short-term and long-term rewards. Within weeks of quitting, blood pressure lowers and blood circulation improves. One year after quitting, the risk for heart disease from smoking decreases by 50%. Five years after quitting, your risk of certain cancers caused by smoking decreases by 50%. Research also shows that stopping smoking is key to manage the many contributors to heart attack. These include atherosclerosis, thrombosis, coronary artery disease, and cardiac arrhythmias.

Getting help to quit

Quitting smoking is both a mental and a physical undertaking. Mentally, you should be ready and fairly stress-free. Physically, you need to commit to exercising daily and getting plenty of sleep. You must overcome 2 obstacles: a physical addiction to nicotine and a habit. The American Cancer Society offers these tips to help users quit using tobacco products:

  • Think about why you want to quit

  • Pick a stress-free time to quit

  • Ask for support and encouragement from family and friends


  • Get plenty of rest

  • Eat a balanced diet

  • Join a smoking cessation program or other support group

In some cases, smokers benefit from nicotine replacement products to help break their smoking habit. Nicotine replacement products continue to give smokers nicotine to meet their nicotine craving. But the benefit of these products is that they don't have the tars and poisonous gases that cigarettes give off. Pregnant or nursing women and people with other health conditions should talk with their healthcare provider before using any nicotine replacement products. Some examples of nicotine replacement products include:





Non-nicotine options to quit smoking

Bupropion. This is a non-nicotine pill to help people stop smoking. It was approved in 1997 by the FDA. Bupropion has been shown to change mood transmitters in the brain that are linked to addiction. It must be prescribed by a healthcare provider. Bupropion may not be right for everyone. Talk with your healthcare provider for more information.

Varenicline. This is also a non-nicotine pill to help with quitting smoking. It was approved by the FDA in 2006. It is the first medicine that targets the nicotine receptors in the brain. Varenicline attaches to the receptors and blocks nicotine from reaching them. This decreases the desire for nicotine. Varenicline may not be right for everyone. Talk with your healthcare provider to see if this is a good option for you.

Electronic cigarettes (e-cigarettes or vaping)

E-cigarettes are very popular among teens. The user inhales a vaporized, heated nicotine-containing liquid instead of smoking cigarettes. This is also called vaping.

Some people use e-cigarettes to help quit smoking. But they are not approved by the FDA as a quit-smoking aid. And it’s not clear they are an effective quit-smoking tool.

E-cigarettes may be harmful. They may have substances that can cause cancer. They have also been linked to severe lung disease. Some people have died from this. Experts are not sure exactly what has caused these illnesses. They don’t seem to be caused by lung infections. But all of the people who developed these lung conditions had used e-cigarettes. Most people who became sick used e-cigarettes that contained the chemical THC. This is the main active ingredient in marijuana. Some people became ill after using e-cigarettes with both THC and nicotine. Others got sick after using only nicotine e-cigarettes. The CDC calls this EVALI (e-cigarette or vaping product use-associated lung injury). Experts don't know if people who have had EVALI are at higher risk for severe complications from the flu (influenza) or other viral lung infections. Healthcare providers recommend a yearly flu shot for everyone over 6 months of age, including people who have had EVALI.

Because of these and other health risks, experts advise people not to use e-cigarettes.

Online Medical Reviewer: Lu Cunningham
Online Medical Reviewer: Mandy Snyder APRN
Online Medical Reviewer: Steven Kang MD
Date Last Reviewed: 3/1/2019