Smoking, and its harmful substances such as nicotine, can harm almost every part of the body, including the brain. It can also lead to other brain conditions, such as cancer, dementia, and stroke.

Smoking is the leading cause of preventable, premature death in the United States.

Studies show that smoking has a negative effect on multiple cognitive functions, and the American Heart Association (AHA) recommends quitting smoking to preserve brain health.

This article discusses the effects that smoking has on the brain and whether quitting smoking makes a difference.

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Nicotine is a highly addictive substance that gives the body a rush of endorphins when it enters the bloodstream and increases dopamine levels. Over time, a person needs more nicotine to feel that dopamine reward.

Repeated exposure to nicotine can alter circuits in the brain involved with stress, learning, and self-restraint. If a person has been smoking for a long time, these brain changes can often result in addiction which can lead to withdrawal symptoms such as irritability, anxiety, problems with memory, and difficulty concentrating.

Studies have shown that nicotine can enhance certain effects on the brain, including accuracy, maintaining attention, fine motor skills, and short-term memory. These short-term enhancements can become addictive, which alongside withdrawal symptoms, can make it extremely difficult to quit smoking.

Studies suggest that metals such as iron, copper, and zinc — which appear in cigarette smoke — can build up in the body and impair cognitive functions.

Studies alsoshow that smoking creates changes in white matter (WM) lesions on the brain, which can cause a decline in cognitive functions.

Over time, smoking can impair cognitive functions such as:

  • information processing
  • memory
  • concentration

A study published in 2018 suggests that smoking can cause a decrease in brain volume. It also suggests that the more cigarettes a person smokes, the greater the decrease in brain volume.

If a person has a lower brain volume, they are typically more likely to have a decline in their cognitive functions.

Smoking tobacco can increase the risk of stroke. Smoking tobacco can make the blood sticky and more likely to clot, which can lead to a stroke. Smoking can also increase levels of harmful cholesterol known as LDL, which can increase the risk of a stroke.

Nicotine and carbon monoxide in cigarette smoke can also lead to a stroke. Carbon monoxide can reduce the amount of oxygen in the blood while nicotine can speed up the heart rate. Both can lead to high blood pressure, which is one of the leading causes of a stroke.

A person who smokes 20 tobacco products per day may be 6 times more likely to have a stroke than a person who does not smoke.

According to a 2015 study, people who smoke are 30% more likely to develop dementia than people who do not.

Studies show that smoking can lead to a reduced volume of gray matter (GM) in the brain. When a person has less GM on the brain, they may be more likely to develop dementia.

Smoking tobacco is the greatest risk factor for developing lung cancer.

Approximately 40% of people with lung cancer may develop brain metastasis which is a form of cancerous brain tumor. Studies show that a person with lung cancer who smokes and inhales nicotine is more likely to develop brain metastasis than a person who does not smoke.

E-cigarettes are still a relatively new product, so there is a limited amount of research on their short-term and long-term health effects.

However, e-cigarettes contain nicotine and other harmful substances that may lead to a decline in cognitive functions. Exposure to nicotine can also raise the heart rate, which can lead to high blood pressure and a stroke.

A 2021 study on rats shows that using e-cigarettes can impact learning and memory functions. In young adults, using e-cigarettes may lead to poor performance in school, trouble concentrating, spontaneous behavior, difficulty sleeping, impaired cognitive functions, and depression.

The CDC suggests that quitting smoking can improve brain health. Over time it can also decrease the risk of having a stroke and developing brain conditions such as dementia.

Some tips for an action plan to quit smoking can include:

  • picking a date to quit that is not too far away and sticking to it
  • listing the reasons why a person is quitting smoking
  • telling family and friends that a person is quitting smoking so they can be supportive
  • using quit smoking support such as the Smokefree app, phoning a quitline such as the National Cancer Institute Quitline, or speaking with a quit smoking counselor such as LiveHelp
  • listing triggers and cravings and what a person can do to distract themselves

An individual can also speak with a healthcare professional for more ways to help them quit smoking.

Learn more tips on quitting smoking.

The following are some questions people frequently ask about the effects smoking has on the brain.

How does smoking affect you mentally?

Smoking can impact mental health in several ways, including:

  • difficulty sleeping
  • causing anxiety, stress, and depression
  • stopping medications for depression and anxiety from working
  • worsening symptoms of PTSD

How long does it take for smoking to affect your brain?

When a person inhales nicotine, it takes approximately 10 seconds for it to reach the brain and for the dopamine release to take effect.

Can your brain recover from smoking?

Research suggests that nicotine takes 24 hours to leave the bloodstream, therefore reducing the risk of any more damage to cognitive functions. After approximately 5–10 years, the risk of having a stroke decreases. It can take up to 25 years after a person quits smoking for parts of the brain to recover.

Smoking tobacco and inhaling nicotine is extremely addictive and can harm any part of the body, including the brain. Studies show that when a person smokes, their cognitive functions can decline.

Individuals who smoke may also be more at risk of conditions such as dementia and stroke.

Products such as E-cigarettes may be less harmful than smoking tobacco. However, they still contain nicotine which can lead to cognitive decline and other behavioral issues.

It is possible for the brain to recover from the effects of smoking once a person quits.

If an individual is interested in quitting smoking, they should speak with a healthcare professional for more information.