Effects of Nicotine on the Brain and the Body

​When nicotine enters the body, it initially causes the adrenal glands to release a hormone called adrenaline. The rush of adrenaline stimulates the body and causes an increase in blood pressure, heart rate, and breathing.

Most of the harm to the body is not from the nicotine, but from other chemicals in tobacco or those produced when burning it—including carbon monoxide, tar, formaldehyde, cyanide, and ammonia. Tobacco use harms every organ in the body and can cause many problems. The health effects of smokeless tobacco are somewhat different from those of smoked tobacco, but both can cause cancer.

Secondhand Smoke
People who do not smoke but live or hang out with smokers are exposed to secondhand smoke—exhaled smoke as well as smoke given off by the burning end of tobacco products. Just like smoking, this also increases the risk for many diseases. Each year, an estimated 58 million Americans are regularly exposed to secondhand smoke and more than 42,000 nonsmokers die from diseases caused by secondhand smoke exposure.2 One in four U.S. middle and high school students say they've been exposed to unhealthy secondhand aerosol from e-cigarettes.

The chart below lists the health problems people are at risk for when smoking or chewing tobacco or as a result of exposure to secondhand smoke.

Nicotine and the Brain
Like other drugs, nicotine increases levels of a neurotransmitter called dopamine. Dopamine is released normally when you experience something pleasurable like good food, your favorite activity, or spending time with people you care about. When a person uses tobacco products, the release of dopamine causes similar effects. This effect wears off quickly, causing people who smoke to get the urge to light up again for more of that good feeling, which can lead to addiction.

A typical smoker will take 10 puffs on a cigarette over the period of about 5 minutes that the cigarette is lit. So, a person who smokes about 1 pack (25 cigarettes) daily gets 250 “hits” of nicotine each day.
Is Nicotine Addictive?

Yes. It is the nicotine in tobacco that is addictive. Each cigarette contains about 10 milligrams of nicotine. A person inhales only some of the smoke from a cigarette, and not all of each puff is absorbed in the lungs. The average person gets about 1 to 2 milligrams of the drug from each cigarette.

Studies of widely used brands of smokeless tobacco showed that the amount of nicotine per gram of tobacco ranges from 4.4 milligrams to 25.0 milligrams. Holding an average- size dip in your mouth for 30 minutes gives you as much nicotine as smoking 3 cigarettes. A 2-can-a-week snuff dipper gets as much nicotine as a person who smokes 11⁄2 packs a day.

Whether a person smokes tobacco products or uses smokeless tobacco, the amount of nicotine absorbed in the body is enough to make someone addicted. When this happens, the person continues to seek out the tobacco even though he or she understands the harm it causes. Nicotine addiction can cause:
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• tolerance: Over the course of a day, someone who uses tobacco products develops tolerance—more nicotine is required to produce the same initial effects. In fact, people who smoke often report that the first cigarette of the day is the strongest or the “best.”
• withdrawal: When people quit using tobacco products, they usually experience uncomfortable withdrawal symptoms, which often drive them back to tobacco use. Nicotine withdrawal symptoms include:
  
  • irritability
  • problems with thinking and paying attention
  • sleep problems
  • increased appetite
  • craving, which may last 6 months or longer, and can be a major stumbling block to quittingHow E-cigarettes Affect the Brain Research so far suggests that e-cigarettes may be less harmful than cigarettes when people who regularly smoke switch to them as a complete replacement. But since they are so new, we do not know for sure. And, nicotine in any form is a highly addictive drug. Health experts have raised many questions about the safety of these products, particularly for teens:

• Testing of some e-cigarette products found the aerosol (vapor) to contain known cancer-causing and toxic chemicals, and particles from the vaporizing mechanism that may be harmful. The health effects of repeated exposure to these chemicals are not yet clear.
• There is animal research which shows that nicotine exposure may cause changes in the brain that make other drugs more rewarding. If this is true in humans, as some experts believe, it would mean that using nicotine in any form would increase the risk of other drug use and for addiction.
• Some research suggests that e-cigarette use may serve as a “gateway” or introductory product for youth to try other tobacco products, including regular cigarettes, which are known to cause disease and lead to early death. A recent study showed that students who have used e-cigarettes by the time they start 9th grade are more likely than others to start smoking traditional cigarettes and other smoked tobacco products within the next year.10

• The liquid in e-cigarettes can cause nicotine poisoning if someone drinks, sniffs, or touches it. Recently there has been a surge of poisoning cases in children under age 5. There is also concern for users changing cartridges and for pets.
• Some research shows that secondhand e-cig vapor pollutes the air quality with particles that could harm the lungs and heart.11
• Some research suggests that certain brands of e-cigs contain metals like nickel and chromium, possibly coming from the heating of coils.12Regulation of E-cigarettesYes. The U.S. Food and Drug Administration (FDA) announced in 2016 that the FDA will now regulate the sales of e-cigarettes, hookah tobacco, and cigars. Therefore:

• It is now illegal to sell e-cigarettes, hookah tobacco, or cigars in person or online to anyone under age 18.
• Buyers have to show their photo ID to purchase e-cigarettes, hookah tobacco, or cigars, verifying that they are 18 years or older.
• These products cannot be sold in vending machines (unless in an adult-only facility).
  
• It is illegal to hand out free samples.
  
  

FDA regulation also means that the Federal government will now have a lot more information about what is in e-cigarettes, the safety or harms of the ingredients, how they are made, and what risks need to be communicated to the public (for example, on health warnings on the product and in advertisements). They will also be able to stop manufacturers from making statements about their products that are not scientifically proven.

Regulation does not mean that e-cigarettes are necessarily safe for all adults to use, or that all of the health claims currently being made in advertisements by manufactures are true. But it does mean that e-cigarettes, hookah tobacco, and cigars now have to follow the same type of rules as cigarette manufacturers.

Source: National Institute on Drug Abuse; National Institutes of Health; U.S. Department of Health and


Thom Kessler, LMFT, RAS
[email protected]
415-454-8931