Smoking & Your Brain: Behavioral Effects

According to the CDC (Center For Disease Control and Prevention), tobacco consumption is the leading cause of preventable death in the United States, with half a million Americans dying prematurely each year as a result. 

While commonly understood consequences of heavy smoking are various forms of cancer, heart disease, lung disease and a high risk of stroke, there are also many different effects that smoking has on the brain, not to mention associated behavioral effects. 


Despite its long term popularity, anti-smoking movements have been around almost as long as the drug’s availability. 

The 1700s

Dr Benjamin Rush, an early American physician, the surgeon general under George Washington, and a prominent signer of the Declaration of Independence was a vocal opponent of habitual smoking. 

As early as 1798, he stated his beliefs that prolonged, habitual smoking led to rises in alcohol consumption and addiction, caused health problems, moral ineptitude, and disrespectful to those non-smokers who chose to abstain from smoking. 

The Early 1900s

As commercial production of cigarettes became industrialized in the 1920s, the negative health consequences of tobacco consumption were starting to be realized. 

Due to the people leading better, generally cleaner lives, the lifespan began to increase, leading to more people reaching old age, where the effects of a lifetime of smoking could be seen as clear as day. 

Along with anti-liquor groups, who had helped achieve American prohibition between 1919 and 1933, anti-smoking groups became more prevalent during this period of extremes. 

Whilst publicly, society seemed to be morally decent, sober, and clean, behind closed doors and in the speakeasies around the US, people were drunker and wilder than ever before. 

Whilst opponents of smoking and drinking were chiefly concerned with religious and moral reasons for the abandonment of such substances, health was also a concern amongst temperance groups, who claimed distinct links between smoking and illness. 

After Fritz Lickint of Dresden, Germany, published a paper in 1929, which drew statistical links between smoking and cancer, anti-smoking movements did begin to regain traction in Europe. 

Even during the Nazi regime, Adolf Hitler publicly condemned smoking, initially putting his own former habit down as a waste of money, and an unhealthy pursuit, before going one step further during the height of power, where he stated that smoking (especially amongst women) was not only immoral, but made women unsuitable to be wives and mothers. 

This fed into his Nazi procreation policies, seeing births rise during this period, and the prevalence of civilian smoking fade somewhat during the war years. 

The Mid-Late 1900s

By 1964, widely published evidence was released in a US surgeon general’s report which drew a clear relationship between smoking and cancer. 

By 1986 further research had also confirmed that passive (or second-hand) smoking was also harmful, and whilst not as dangerous, could still lead to cancer over long periods of time. 

The 2000s & Beyond

In modern times, the negative health effects are widely understood, and whilst still legal, many measures have been brought into place to try to counteract it. 

This includes heavy taxes on tobacco products in an attempt to outprice consumers and purveyors, the ban on indoor smoking (in bars and restaurants), and the banning of vibrant packaging and TV ads in the United Kingdom. 

Despite this however, many people are still ignorant of the underlying impact of prolonged smoking on the body and brain, and many people continue to smoke to this day. 

Impact On The Brain

Whilst the heart and lungs are the organs most commonly associated with smoking related illnesses, the brain is also greatly affected by prolonged habitual smoking. 


Smoking has been proven to rapidly age the brain over long periods of use, with two symptoms being memory impairment and diminished cognitive function. 

Memory can be affected by prolonged reduction of oxygen to the brain. When we smoke, our lungs receive less oxygen due to the smoke and burning embers ingested, and as such our brain receives less oxygen through the blood cells. 

Studies have even shown that people who smoke heavily find it harder to put faces to people’s names, and even struggle to recall memories in some extreme cases. 


As you probably know, adrenaline is a chemical naturally produced in the human body, which acts as an effective danger alarm, playing an important part in our ingrained fight or flight response, and providing us with the added strength, speed, and pain relief to avoid harmful situations as best we can. 

The presence of nicotine in the body from smoking can trigger a rise in the levels of adrenaline, causing false danger warnings in our body and facilitates a heightened emotional state and a feeling of defensiveness and being on edge. 


There is a common misconception that smoking reduces stress, or that it is relaxing, and whilst that might be true within the first 30 minutes of smoking a cigarette, the amount of stress we feel is heightened substantially after that point. 

This is why we feel irritable when we haven’t had a cigarette, and why smoking can actually increase anxiety over time. 


Prolonged smoking means that the brain adapts to operating under the influence of nicotine. This means that once the brain has rewritten itself in this way, it becomes a dependence, making it harder to stop smoking. 

When stopping smoking, the body and brain find it difficult to respond to a natural state in a positive way, altering mood balances, and making normally occurring stimuli intolerable or unpleasant. 

This can lead to social, medical, or psychological problems over time, especially if unmanaged or untreated. 

Fat Burning

Whilst many may think burning fat is a good thing, this is not a healthy way to live, nor is it a healthy alternative to exercise or a good diet. 

Smoking increases the metabolic rate of the body, leading to the burning of fats, and eventually weight loss. It also increases caffeine tolerance, meaning you will need to drink more to feel the effects.  


Smoking causes frequent releases of the feel-good hormone called dopamine, meaning that not only do we feel good when we have a cigarette, but it makes it harder for our brains to give up smoking when the time comes. 

The Effects Of Withdrawal

The withdrawal effects of smoking can cause similar behavioral issues, albeit at a more sporadic and unpredictable rate. 

Causing anxiety, nausea, and mood swings, nicotine withdrawal has been known to also cause irritability and heightened stress. 

Final Thoughts

And there we have it, our breakdown of the relationship between smoking and the human brain, as well as the subsequent behavioral and physical side effects of long term use and withdrawal. 

If you have quit smoking, or are in the process, be rest assured that there are plenty of options out there to ease your transition, and plenty of groups and therapy sources to give you a helping hand if you need it. 

Why not give it a try? Your body and brain will definitely thank you for it later!

Jonie Dean
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