Cigarette smoking is the leading contributor to preventable deaths in the United States. Smoking can result in chronic conditions that affect the heart, circulatory and respiratory systems, contributing or causing more than 25 specific diseases, according to the Surgeon General.
Smokers face a much higher risk of life-threatening events such as heart attack and stroke. Tobacco use is blamed for more than 437,000 deaths each year from all causes, including heart attack and stroke, according to the American Heart Association’s Heart Disease and Stroke Statistics – 2007. About 34 percent of these deaths were cardiovascular related.
Nonsmokers are also at risk. Experts estimate that a nonsmoker who is exposed to secondhand (or slipstream) tobacco smoke (at work or in the home) faces a 30 percent higher risk of coronary artery disease than someone not exposed to secondhand smoke. About 35,000 nonsmokers are estimated to die every year from smoking-related coronary artery disease.
Besides the human toll, smoking carries a hefty economic price. Medical costs for smoking-related conditions exceed $157 billion annually in the United States. Worldwide, the magnitude of this problem is even greater – smoking causes or contributes to 3.5 million deaths every year.
Cigarette smoking can make otherwise uncommon medical problems more likely. Lung cancer, for instance, was rarely encountered up to the early 20th century. By the 1930s (about 40 years after mass-produced cigarettes appeared on the market) physicians began seeing an increase in the number of lung cancer cases.
In 1950, the landmark study by British doctors Richard Doll and Austin Hill concluded that cigarette smoking is an “important factor” in the production of lung cancer. The research was widely publicized and sparked anti-smoking campaigns around the world. In 1964, a report by the U.S. Surgeon General acknowledged the connection between smoking and cancer. A second Surgeon General report in 1988 stated that nicotine and tobacco produce addiction levels similar to heroin or cocaine.
Every Surgeon General’s report since then had added to the list of disease caused by smoking. Today, in addition to lung cancer, heart disease, chronic obstructive pulmonary disorder and stroke, smoking has been linked to:
- Abdominal aortic aneurysm
- Cancer of the cervix, kidney, pancreas, stomach, bladder, esophagus, larynx and throat
- Gum disease
- Sudden infant death syndrome (SIDS)
Researchers have estimated that smoking cuts an average of 10 years off a person’s life expectancy, even with advances in prevention and treatment of the various diseases associated with smoking. However, by quitting early these “lost” years can be regained. A person who quits at age 35 can live as long as nonsmokers, according to recent studies.
Cigarette smoking is the leading contributor to preventable deaths in the United States. According to the U.S. Centers for Disease Control and Prevention (CDC), more than 442,000 deaths in the United States are due to tobacco use each year (about 20 percent of the total mortality throughout the country). More than 179,000 of these deaths are from cardiovascular diseases, including stroke. Smokers also face very high risks of developing respiratory diseases that have no cure, such as chronic obstructive pulmonary disease, lung cancer and other smoking related diseases.
On average, adults who smoke die 13 to 14 years earlier than nonsmokers. Also at risk are individuals exposed to secondhand smoke. Such “involuntary” smoking is responsible for approximately 3,000 lung cancer deaths annually among non-smokers and 300,000 respiratory tract infections among children. Based on current cigarette smoking patterns, an estimated 6.4 million people younger than 18 will die prematurely of smoking-related diseases, according to the CDC. The direct medical cost of tobacco use in the United States is estimated at more than $75 billion annually.
The CDC estimates that in recent years, the number of Americans who smoke has consistently dropped, down from a high of more than 50 percent in the 1960s to less than 25 percent of Americans today. Much of this progress may be due to extensive public education campaigns that seek to educate people about the dangerous toxins in tobacco smoke and prevent young people from becoming smokers.
Tobacco smoke contains more than 4,000 chemical compounds, including:
- Nicotine. A highly addictive chemical that goes straight to the brain in as little as 10 seconds and has effects throughout the rest of the body. This is the chemical largely responsible for “hooking” people on cigarettes (a smoking addiction).
- Tar. A term used to describe the 20 (or more) carcinogens (cancer-causing substances) found in tobacco smoke that form a sticky, tar-like substance within the lungs.
- Carbon monoxide. Replaces some of the essential oxygen in the bloodstream. With less oxygen, the major organs of the body and linings of the blood vessels are damaged over time, directly contributing to conditions such as hardened arteries (atherosclerosis).
Smoking can have devastating effects on many systems of the body, especially the cardiovascular system. It is a major cause of high blood pressure (hypertension) as well as heart failure, coronary artery disease, heart attack, stroke and other cardiovascular conditions.
Smoking is also the “great equalizer” for heart disease in women. Among non-smokers, men overall have a much greater risk of acquiring heart disease than women who have not yet gone through menopause. However, female smokers’ risk of heart disease can be as much as six times greater than female non-smokers. This risk is exponentially increased in women receiving contraceptive pills. Pregnant and breast-feeding smokers also risk the health of the child, both before the birth and afterward, due to the effects of second-hand (passive) smoke.
Specifically, smoking affects the cardiovascular system in the following ways:
- Stimulates the formation of a blood clot, which can quickly and suddenly obstruct a blood vessel.
- Damages areas on the walls of the arteries. These become attractive spots for plaque to form, which could lead to hardened arteries (atherosclerosis).
- Higher levels of fatty materials triglycerides and “bad” low-density lipoproteins, (LDL) cholesterol – two dangerous elements in the development of hardened arteries (atherosclerosis). Smokers also have lower levels of “good” high-density lipoproteins (HDL) cholesterol.
- Has been linked to sudden cardiac death of all types in both men and women.
Other tobacco or smoking products such as chewing tobacco and snuff are harmful as well. Furthermore, people who smoke other products (e.g., “light” cigarettes or clove cigarettes) are also facing serious health risks. The risk for cancers of the mouth, esophagus, larynx and bladder are also increased in pipe and cigar smokers. Because of the many dangers of smoking, people are encouraged to speak with their physician about strategies that are available to help them quit.
About nicotine addiction
It is difficult to quit smoking because the nicotine in tobacco smoke is so addictive. Nicotine impacts the central nervous system, causing a release of epinephrine, a hormone that causes a “rush” of energy. After this stimulus subsides, a sedative effect takes over. This rapidly progresses to withdrawal symptoms that compel the smoker to reach for another cigarette.
One particularly ominous aspect of a smoking (or most any drug) habit is that the user becomes sensitized to the addictive component of the substance – in this case, nicotine. Consequently, the number of cigarettes needed to retain that same metabolic “rush” is increased, leading smokers to steadily increase their intake of cigarettes. Naturally, this also complicates withdrawal from nicotine.
The higher the circulating levels of nicotine, the more difficult it is to quit and the more severe the withdrawal symptoms, including:
- Difficulty concentrating or paying attention
- Trouble sleeping
- Increased appetite (although some experts believe people eat more after quitting smoking because food is regaining full flavor for them)
These withdrawal symptoms may begin within a few hours of the last cigarette and generally grow more severe, peaking after a few days and subsiding in a few weeks.
Not all tobacco users are addicted to nicotine. Nicotine dependence is marked by the following:
- Serious, yet unsuccessful attempts to stop tobacco use.
- Physical withdrawal symptoms during periods of quitting smoking.
- Continued tobacco use despite a serious physical problem that the user knows is made worse through continued tobacco use, such as cardiovascular disease, respiratory illness or cancer.
- User has developed a tolerance for nicotine created by the accumulation of nicotine in the body. Each additional intake produces less of an effect, causing the user to increase the frequency and or amount of nicotine intake.
Nicotine is also psychologically addictive. It delays the breakdown of the nerve impulse that influences alertness, pain reduction, learning and memory (acetylcholine). As a result, nicotine stimulates memory and alertness, and improves mental speed and reaction time. Nicotine may also alter the user’s mood by stimulating the production of the brain’s “pleasure” chemicals, including dopamine, beta-endorphin, epinephrine, norepinephrine, arginine and vasopressin. Nicotine reduces stress and the body’s aggressive response to stressful situations. Furthermore, nicotine suppresses the appetite, especially for sweets (simple carbohydrates). For some users, the ritual act of smoking itself (e.g., the holding and lighting of the cigarette) is part of the pleasure.
Because of this emotional as well as physical addiction, people may continue to experience cravings for nicotine even months after they have quit smoking. In other words, they may still crave nicotine for emotional reasons even after nicotine is no longer affecting their body physically. Ex-smokers who are tempted to “give in” and begin smoking again are strongly encouraged to speak with a trusted friend, family member or health care professional.
Toxins in tobacco smoke
Tobacco is the only natural source of nicotine and cigarettes have often been described as a “nicotine delivery device.” Nicotine is unusual because it can act as both a stimulant and a depressant when absorbed by the body. Why these dual reactions occur is not completely understood.
Nicotine reaches the brain within as little as 10 seconds. There, the nicotine changes the brain’s metabolic and electrical activity, as well as regulation of hormones and neurotransmitters (chemicals that control bodily functions). These changes cause the following negative reactions in the body:
- Increased heart rate by five to 10 beats per minute due to the release of a stress hormone (adrenaline).
- Constricted blood vessels, resulting in higher blood pressure.
- Greater collection of the body’s natural blood-clotters (platelets), which may lead to thrombosis (formation of blood clots), embolism (obstruction of a blood vessel by a clot) or heart attack.
- Increased saliva and sweat production.
- Increased bowel activity, which may result in diarrhea.
- Increased bronchial secretions and depressed respiratory muscles.
- Stimulated central nervous system, which in high doses may result in nausea, tremors or even convulsions.
- Increased glucose (blood sugar), but also less insulin – a chemical compound produced in the pancreas that helps the body process glucose. As a result, many smokers have slightly higher blood glucose (hyperglycemia).
Individuals have different sensitivities to nicotine and flush the drug out of their system at different speeds. This may account for variations of how often, and how much, tobacco users feel they need to smoke. Once the drug is out of a smoker’s system, that person begins to feel the effects of withdrawal (i.e., a “nicotine fit”). Studies have proven that after four hours without nicotine, withdrawal can interfere with work performance.
It is also possible to overdose on nicotine, which could produce symptoms such as:
- Mouth sores
- Muscle twitching
- Abdominal cramps
- Difficulty breathing
Effects of tar in tobacco smoke
Tar is a term used to describe the different carcinogens found in tobacco smoke that form a sticky, tar-like substance within the lungs. This substance irritates the lungs and respiratory system and is considered to be a major cause of lung cancer, bronchitis, emphysema and chronic obstructive pulmonary disease. So-called “low tar” cigarettes have shown to have little benefit, for those wishing to cut down on tar intake – many smokers compensate by taking longer, more intensive puffs. As a result, there has been a rise in cancers occurring in deeper areas of the lungs.
Effects of carbon monoxide in tobacco smoke
Carbon monoxide is a colorless, odorless, tasteless gas present in tobacco smoke. Other common sources are home furnaces and automobile engines. When tobacco smoke brings carbon monoxide into the body, it is absorbed into the bloodstream and begins to replace the oxygen normally carried by red blood cells to vital tissues and organs. Over time, the body’s organs cannot operate as efficiently because of the decrease in oxygen. Additionally, blood vessel linings are damaged, which contributes to atherosclerosis, a leading cause of heart attack and stroke.
Though lethal levels of carbon monoxide are not typically reached through smoking alone, smokers have a lower threshold for carbon monoxide poisoning due to the amount of the gas already present in their bodies. Carbon monoxide poisoning can lead to any of the following:
- Feeling tired or fatigued
- Rapid pulse
- Blurred vision
- Chest pain
Other smoking products
There are a variety of other products that people choose to smoke besides the major cigarette brands on the market. These include:
- Cigars and pipes
- Clove cigarettes
- Bidis (“bee dees”)
- “Low-tar” or “light” cigarettes
- Smokeless tobacco
Cigars and pipes
Cigars and pipes are often considered to be a less risky way for people to smoke, because most of the smoke is not inhaled. Cigars in particular have been growing in popularity over the last several years, especially among younger people. However, both methods do increase the risk for heart disease significantly, as well as many types of cancer and periodontal disease. The fact is, there is no “safe” way to smoke.
Cigars and pipe carry many of the same the same health risks as cigarette smokers, including death from all forms of cancer, high blood pressure and other circulatory problems.
Recent research has found that, although cigars are not as dangerous to overall health as cigarettes, they still carry considerable risk. For example, smoking cigars increases the risk of death from coronary artery disease. Pipes also carry much higher health risks, including a fourfold increase in the risk of throat cancer and increased cancer risk of the esophagus, larynx, colon and pancreas.
Clove cigarettes (also known as “kreteks”) contain clove buds as well as tobacco. The clove buds contain an anesthetic (eugenol) that can numb the back of the throat. This impairs the normal gag reflex that protects the lungs from inhaling foreign materials. Use of clove cigarettes carries all the same risks as traditional tobacco products as well as the additional risks associated with inhaling foreign materials into the lungs, including pneumonia, bronchitis and lung abscesses.
Bidis (pronounced bee-dees) are hand-rolled, unfiltered cigarettes made in India. Once available only in specialty tobacco shops, bidis are now widely available in the United States. They are the latest fad in American tobacco use, especially among teens. This may be due to their low cost and the fact that bidis exported to the United States are produced in youth-tempting flavors like strawberry, vanilla, chocolate and black licorice. Although many teens mistakenly think that bidis contain no tobacco because of the flavor and the greener color inside, they can release two to three times more tar and nicotine than American-made cigarettes. In India, bidi smoking is associated with a threefold increase in cardiovascular disease and heart attack risk. They are also associated with a fourfold increase in chronic bronchitis, according to the Center for Disease Control and Prevention (CDC).
Low-tar or light cigarettes
According to their packaging, “low tar” or “light” cigarettes contain about 50 percent less tar than standard cigarettes. Unfortunately, most smokers who switch to lighter cigarettes do not reduce their tar levels by 50 percent because they generally take larger puffs and inhale more deeply when smoking “light” tobacco products. Smokers may also have a tendency to smoke more frequently after switching to a “light” product. Therefore, an individual who switches from regular to “light” tobacco products may only reduce their intake of tar and nicotine by about 30 percent or less.
Many people think that smoking marijuana is safer than smoking cigarettes. However, marijuana contains many of the same harmful chemicals that cigarettes do. Some researchers believe that smoking five marijuana cigarettes (“joints”) per week can harm the body as much as smoking a pack of cigarettes every day. Therefore, marijuana may actually raise the risk of lung cancer even higher than cigarettes do. Research has also suggested that marijuana can increase the heart rate by as much as 50 percent, cause stroke in very rare cases and interfere with the functioning of the immune system.
Smokeless tobacco products
There are two forms of “smokeless tobacco”: chewing tobacco and snuff. Chewing tobacco (shredded tobacco leaves) is typically placed between the lip and gums, causing extra saliva that is spit out frequently. Snuff was formerly used in Europe a “pinch” at a time, inhaled through the nostrils. Today the substance is more commonly placed (or dipped) in the mouth, where it immediately dissolves and rapidly enters the bloodstream.
Contrary to popular belief, the use of chewing tobacco or snuff produces the same negative health effects as smoking. In addition, they carry an increased risk of mouth lesions, oral cancer, and dental problems such as loose teeth or gum disease.
Questions for your doctor
Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions related to smoking:
- How can I tell if I am addicted to smoking?
- Specifically, how is smoking affecting my condition?
- If I have respiratory problems caused by smoking, is it ok to switch to smokeless tobacco products?
- Has the smoking I have done in the past done irreparable damage to my health?
- If I quit smoking, how long will it be before I start to notice the health benefits?
- What’s the best way to approach my loved one about quitting smoking?
- Where can I get help with trying to quit smoking?
- What would be the immediate heath consequences if I did not stop smoking?
- Could my smoking affect any of the people who live in the same home?
- Could smoking cigarettes make it harder for me to get pregnant?