Most people who smoke started smoking when they were teenagers. Those who have friends and/or parents who smoke are more likely to start smoking than those who don’t. Some teenagers say that they “just wanted to try it,” or they thought it was “cool” to smoke.
The tobacco industry’s ads, price breaks, and other promotions for its products are a big influence in our society. The tobacco industry spends billions of dollars each year to create and market ads that show smoking as exciting, glamorous, and safe. Tobacco use is also shown in video games, online, and on TV. And movies showing people smoking are another big influence. Studies show that young people who see smoking in movies are more likely to start smoking.
A newer influence on tobacco use is the e-cigarette and other high-tech, fashionable electronic “vaping” devices. Often wrongly seen as harmless, and easier to get and use than traditional tobacco products, these devices are a way for new users to learn how to inhale and become addicted to nicotine, which can prepare them for smoking.
Anyone who starts using tobacco can become addicted to nicotine. Studies show that smoking is most likely to become a habit during the teen years. The younger you are when you begin to smoke, the more likely you are to become addicted to nicotine.
According to the 2014 Surgeon General’s Report (SGR), nearly 9 out of 10 adults who smoke started before age 18, and nearly all started by age 26. The report estimates that about 3 out of 4 high school students who smoke will become adults who smoke – even if they intend to quit in a few years.
Addiction is marked by the repeated, compulsive seeking or use of a substance despite its harmful effects and unwanted consequences. Addiction is mental or emotional dependence on a substance. Nicotine is the known addictive substance in tobacco. Regular use of tobacco products leads to addiction in many users. Nicotine is a drug that occurs naturally in tobacco and it’s thought to be as addictive as heroin or cocaine.
Researchers are also looking at other chemicals in tobacco that make it hard to quit. In the brains of animals, tobacco smoke causes chemical changes that are not fully explained by the effects of nicotine.
The average amount of nicotine in one regular cigarette is about 1 to 2 milligrams (mg). The amount you actually take in depends on how you smoke, how many puffs you take, how deeply you inhale, and other factors.
About 2 out of 3 of people who smoke say they want to quit and about half try to quit each year, but few succeed without help. This is because they not only become physically dependent on nicotine. There’s also a strong emotional (psychological) dependence. Nicotine affects behavior, mood, and emotions. If a person uses tobacco to help manage unpleasant feelings and emotions, it can become a problem for some when they try to quit. Someone who smokes may link smoking with social activities and many other activities, too. All of these factors make smoking a hard habit to break.
In fact, it may be harder to quit smoking than to stop using cocaine or opiates like heroin. In 2012, researchers reviewed 28 different studies of people who were trying to quit using the substance they were addicted to. They found that about 18% were able to quit drinking, and more than 40% were able to quit opiates or cocaine, but only 8% were able to quit smoking.
People who inhale cigar smoke absorb nicotine through their lungs as quickly as people who smoke cigarettes. For those who don’t inhale, the nicotine is absorbed more slowly through the lining of the mouth. This means people who smoke cigars can get the desired dose of nicotine without inhaling the smoke directly into their lungs.
Most full-size cigars have as much nicotine as several cigarettes. Cigarettes contain an average of about 8 milligrams (mg) of nicotine, but only deliver about 1 to 2 mg of nicotine. Many popular brands of larger cigars have between 100 and 200 mg, or even as many as 444 mg of nicotine. The amount of nicotine a cigar delivers to a person who smokes can vary a great deal, even among people smoking the same type of cigar. How much nicotine is taken in depends on things like:
Given these factors and the large range of cigar sizes, it’s almost impossible to make good estimates of the amounts of nicotine larger cigars deliver.
Small cigars that are the size and shape of cigarettes have about the same amount of nicotine as a cigarette. If these are smoked like cigarettes (inhaled), they would be expected to deliver a similar amount of nicotine – 1 to 2 mg.
Smokeless tobacco delivers a high dose of nicotine. Nicotine enters the bloodstream from the mouth or nose and is carried to every part of your body.
Nicotine in smokeless tobacco is measured in milligrams (mg) of nicotine per gram (g) of tobacco. It’s been found to vary greatly, for instance as much as 4 to 25 mg/g for moist snuff, 11 to 25 mg/g for dry snuff, and 3 to 40 mg/g for chew tobacco. Other factors that affect the amount of nicotine a person gets include things like:
Still, blood levels of nicotine have been shown to be much the same when comparing people who smoke cigarettes to those who use smokeless tobacco.
Non-combusted tobacco products come in various forms and are used in different ways. Non-combusted products contain nicotine and can lead to nicotine addiction.
The e-liquid in most e-cigarettes (vapes) contains nicotine. However, nicotine levels are not the same in all types of e-cigarettes, and sometimes product labels do not list the true nicotine content.
There are some e-cigarette brands that claim to be nicotine-free but have been found to contain nicotine.
Stopping or cutting back on tobacco causes symptoms of nicotine withdrawal. Withdrawal is both physical and mental. Physically, your body is reacting to the absence of nicotine. Mentally, you are faced with giving up a habit, which calls for a major change in behavior. Emotionally, you might feel like as if you’ve lost your best friend. Studies have shown that smokeless tobacco users have as much trouble giving up tobacco as people who want to quit smoking cigarettes.
People who have used tobacco regularly for a few weeks or longer will have withdrawal symptoms if they suddenly stop or greatly reduce the amount they use. There’s no danger in nicotine withdrawal, but the symptoms can be uncomfortable. They usually start within a few hours and peak about 2 to 3 days later when most of the nicotine and its by-products are out of the body. Withdrawal symptoms can last a few days to up to several weeks. They get better every day that a person stays tobacco-free.
Nicotine withdrawal symptoms can include any of the following:
These symptoms can lead a person to start using tobacco again to boost blood levels of nicotine and stop symptoms.
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
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Last Revised: June 23, 2022
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