Cigarette smoke contains approximately 4,000 chemicals. At least 250 of these are harmful to humans and 50 are carcinogens, according to the National Cancer Institute. Smoking increases your risk of coronary disease or stroke by two to four times and your risk of death from chronic obstructive lung disease by 12 to 13 times. If you are a man and you smoke, your risk of lung cancer is 23 times higher than a nonsmoker; if you're a woman, your risk is 13 times greater than a nonsmoker.
Basics
When you inhale cigarette smoke, the chemicals enter your lungs and make their way into your blood stream. From there, they travel to virtually every part of your body, where they harm organs and tissues. Cigarette smoke also kills some of your alveoli, the air sacks in your lungs that transfer the oxygen you breathe into your blood stream. Alveoli do not regenerate. The smoke also paralyzes the cilia---hairlike structures that move back and forth to sweep particles out of your lungs. Once they are paralyzed, particles build up in your lungs and obstruct airways.
Cancer
Smoking causes cancer not only in the organs it touches directly, such as the mouth, throat, larynx, esophagus and lungs, but also other organs that take in the chemicals that the bloodstream circulates throughout your body. According to the Centers for Disease Control, smoking also causes cancer of the pancreas, bladder, kidney, stomach, cervix and uterus. In addition, it causes acute myeloid leukemia, a cancer that affects the blood and bone marrow.
Cardiovascular Effects
The chemicals in cigarette smoke cause serious damage to the cardiovascular system. Carbon monoxide blocks oxygen from entering the blood and contributes to the formation of cholesterol deposits on the walls of your arteries. Nicotine increases your blood pressure and may contribute to blood clots. All of these effects place a strain on your heart and increase your risk of a heart attack. The diminished oxygen and narrowing of the blood vessels also can lead to a stroke.
Young People
Some people think the effects of smoking only impact people later in life, but smoking has serious implications for young people too. It lowers hormone levels, causes bad breath and increases the risk that a cold will develop into bronchitis or pneumonia. Smokers develop three times more cavities than non-smokers and are more likely to experience gum disease. Teenage smoking is particularly risky because it causes teens to develop smaller lungs and a weaker heart than their non-smoking peers. Smoking also may cause recurring headaches.
Secondhand Smoke
Secondhand smoke comes from both the burning cigarette and the smoke exhaled by a smoker. Nonsmokers inhale the same poisons as the smoker and are subject to many of the same health risks. Approximately 3,000 nonsmokers die each year from exposure to secondhand smoke and it causes an estimated 46,000 heart disease-related deaths yearly, according to the National Cancer Institute. Secondhand smoke interferes with the development of children's lungs and makes them more likely to develop severe asthma, bronchitis and pneumonia as well as wheezing and breathlessness.
Reproductive Health
Smoking lowers hormone levels and puts you at increased risk of infertility. In pregnant women, smoking reduces the amount of oxygen the baby receives and increases the risk of stillbirth and premature delivery. It also puts your baby at risk for low birth weight, asthma and sudden infant death syndrome. Circulatory problems caused by smoking can lead to impotency in men.
References
- Centers for Disease Control and Prevention: Health Effects of Cigarette Smoking
- Center for Young Women's Health: Information About Smoking
- Tennessee Department of Health: How Does Smoking Harm My Baby?
- QuitSmoking.com: How Smoking Affects Your Body
- National Cancer Institute: Secondhand Smoke: Questions and Answers
