Cigarette smoking causes about 1 in 5 deaths in the United States each year. It is the leading preventable cause of death and illness in the United States.

Smoking is harmful to almost every organ in the body, including the heart, blood vessels, lungs, eyes, mouth, reproductive organs, bones, bladder and digestive organs. This article is about how smoking affects the heart and blood vessels.

Other health-related articles, such as COPD (chronic obstructive pulmonary disease), bronchitis and cough, discuss how smoking affects the lungs.

Smoking and your heart and blood vessels

The chemicals in tobacco smoke are harmful to your blood cells. They can also damage the function of your heart and the structure and function of your blood vessels. This damage increases your risk of atherosclerosis.

Atherosclerosis is a disease in which a waxy substance called plaque builds up in the arteries. Over time, plaque hardens and constricts your blood vessels. This limits the flow of oxygenated blood to your organs and other parts of your body.

Ischemic heart disease occurs when plaque builds up in the arteries that supply blood to the heart, called coronary arteries. Over time, heart disease can lead to chest pain, heart attack, heart failure, arrhythmias, or even death.

Smoking is a major risk factor for heart disease. In combination with other risk factors - such as unhealthy blood cholesterol, high blood pressure, and overweight or obesity - smoking further increases the risk of heart disease.

Smoking is also a major risk factor for peripheral artery disease (PAD). PAD is a condition in which plaque builds up in the arteries that supply blood to the head, organs, and extremities. People with PAD are at an increased risk of heart disease, heart attacks and strokes.

Smoking and atherosclerosis

The image shows how smoking can affect the arteries in the heart and legs. Figure A shows the location of coronary artery disease and peripheral artery disease. Figure B shows a detailed view of a leg artery with atherosclerosis - plaque buildup partially blocking blood flow. Figure C shows a detailed overview of a coronary artery with atherosclerosis. Any amount of smoking, even light smoking or occasional smoking, can damage the heart and blood vessels. For some people, such as women on birth control pills and people with diabetes, smoking poses an even greater risk to the heart and blood vessels. Secondhand smoke can also damage the heart and blood vessels. Secondhand smoke is the smoke that comes from the burning end of a cigarette, cigar or pipe. Secondhand smoke also refers to smoke exhaled by a person who smokes.

Secondhand smoke contains many of the same harmful chemicals that people breathe when they smoke. Secondhand smoke can damage the heart and blood vessels of people who do not smoke in the same way that active smoking is harmful to those who smoke. Secondhand smoke significantly increases the risk of heart attack and death in adults.

Secondhand smoke also increases children and teens' risk of future ischemic heart disease because it:

• Lowers HDL cholesterol (also called 'good' cholesterol)
• Increases blood pressure
• Damages heart tissue

The risks of secondhand smoke are especially high for premature babies with respiratory distress syndrome (RDS) and children with conditions such as asthma.

Researchers know less about the influence of cigar and pipe smoke on the heart and blood vessels than about cigarette smoke.

However, the smoke from cigars and pipes contains the same harmful chemicals as the smoke from cigarettes. Studies have also shown that people who smoke cigars are at an increased risk of heart disease.

Benefits of quitting smoking and avoiding secondhand smoke

One of the best ways to reduce your risk of heart disease is to avoid tobacco smoke. Never start smoking. If you already smoke, quit. It doesn't matter how much or how long you've smoked, quitting is good for you.

Also try to avoid secondhand smoke. Do not go to places where smoking is allowed. Avoid asking friends and family members who smoke around the house or in the carto do.

When you quit smoking, you reduce the risk of developing and dying from heart disease. Over time, quitting will also lower the risk of atherosclerosis and blood clots.

If you smoke and already have heart disease, quitting smoking reduces your risk of sudden cardiac death, a second heart attack, and death from other chronic illnesses.

Researchers have studied communities that have banned smoking in workplaces and public places. The number of heart attacks in these communities has dropped significantly. Researchers believe these results are due to a decrease in active smoking and reduced exposure to secondhand smoke.