Cigarettes and other tobacco products provide nicotine, which is a highly addictive substance that provides temporary stimulation and feelings of relaxation. Nicotine affects the brain and central nervous system, causing a rush of dopamine and adrenaline. This gives the smoker a boost of energy and focus. Over time, the body becomes dependent on nicotine and smokers need to keep smoking just to feel normal. So in essence, smokers “run” on nicotine – it provides the lift and rush that keeps them coming back.
The Nicotine Effect
When a smoker inhales tobacco smoke, nicotine is quickly absorbed into the bloodstream and travels to the brain. Nicotine attaches to acetylcholine receptors, which are normally activated by the neurotransmitter acetylcholine. This stimulates the release of other neurotransmitters like dopamine, serotonin, epinephrine, and norepinephrine. These chemicals are part of the “reward pathway” in the brain that controls feelings of pleasure and well-being. Nicotine essentially hijacks this pathway and leads to a pleasant euphoric feeling for the smoker.
In addition to the “feel good” chemicals, nicotine also raises alertness, concentration, and memory due to elevated epinephrine and norepinephrine levels. This provides a boost in energy, focus and performance. Smokers often report being able to think and work more efficiently after lighting up. However, these effects are only temporary and eventually wear off as the nicotine level in the blood drops. This leads to withdrawal symptoms like irritability, anxiousness, and difficulty focusing. The smoker then lights up another cigarette to get rid of these feelings, continuing the cycle of stimulation and withdrawal.
Developing an Addiction
Nicotine stimulates the same reward pathways in the brain that other addictive drugs like cocaine and heroin activate. But unlike those illicit drugs, nicotine in cigarettes is perfectly legal and relatively easy to obtain. Over time, the brain starts to associate smoking with pleasurable effects. Neural pathways become sensitized to nicotine and the smoker starts craving it when not smoking. Smokers become dependent on the drug to function normally throughout the day.
When first trying cigarettes, teenagers report feeling dizzy and nauseated. But over time they build tolerance and need to smoke more frequently to get the same “buzz”. The highly addictive nature of nicotine makes it very difficult to quit smoking once a person is hooked. Even though smokers are aware of the health risks, the cravings and withdrawal symptoms often prevent them from being able to stop.
The Addictive Properties of Nicotine
- Nicotine triggers dopamine release in the brain’s reward pathway
- Pleasant feelings reinforce the smoking habit
- Over time, greater amounts of nicotine are needed to get the same effect
- Neuronal pathways become dependent on nicotine stimulation
- Withdrawal occurs when nicotine levels drop in the body
- Smokers light up again to relieve withdrawal symptoms
Short-Term Physical Effects
Within seconds of inhaling tobacco smoke, the nicotine is absorbed into the bloodstream and transported to the brain. This sets off a cascading series of effects on the body:
- Dopamine release – Nicotine stimulates dopamine release in the brain’s pleasure centers
- Adrenaline surge – Epinephrine (adrenaline) levels rise, which increases blood pressure, heartbeat, and respiration
- Improved focus – Due to the dopamine and adrenaline rush, smokers report feeling more alert and able to concentrate after smoking
- Suppressed appetite – Nicotine reduces appetite and dulls taste buds
- GI motility – Nicotine increases acid production and stimulates bowel movements
- Relaxation – Muscle tension is reduced due to the calming effect of dopamine release
These changes happen rapidly but are short-lived. Within 30-60 minutes the stimulatory effects wear off as nicotine is metabolized and removed from the system. Blood pressure, pulse rate, and respiration return to normal. This withdrawal leads to cravings for another cigarette to get back that temporary stimulation.
Long-Term Health Consequences
While smoking provides an immediate little rush, over the long-term it is extremely damaging to nearly every organ in the body:
| System | Effects of Smoking |
|---|---|
| Respiratory | Chronic obstructive pulmonary disease (COPD), chronic bronchitis, emphysema, lung cancer |
| Cardiovascular | Atherosclerosis, coronary heart disease, stroke, aneurysm |
| Reproductive | Infertility, genetic mutations, impotence, pregnancy complications |
| Endocrine | Insulin resistance, type 2 diabetes |
| Digestive | Stomach ulcers, acid reflux, pancreatic cancer |
| Urinary | Bladder and kidney cancer |
There are over 7,000 toxic chemicals found in tobacco smoke, 69 of which are known to cause cancer. Some of the most dangerous ones include:
- Arsenic
- Benzene
- Cadmium
- Formaldehyde
- Lead
- Toluene
These toxins damage cell DNA and cause genetic mutations that lead to cancer. They also impair immune function, making smokers more susceptible to infections.
Health Risks of Secondhand Smoke
Secondhand smoke also exposes non-smokers to the same cancer-causing agents. There is no safe level of exposure. According to the CDC, secondhand smoke causes over 41,000 deaths per year in the U.S. among nonsmoking adults and over 400 infant deaths from SIDS.
Quitting Smoking
Kicking the nicotine addiction is extremely challenging due to the withdrawal symptoms that occur. But quitting smoking is absolutely critical to improve long-term health outcomes. Some tips to quit smoking include:
- Set a quit date and stick to it
- Throw away all cigarettes and ashtrays
- Tell family and friends you are quitting for support
- Get rid of smoking triggers like alcohol
- Try nicotine replacement like gum or patches
- Join a smoking cessation program or counseling
- Take up exercise or hobbies to manage stress
- Consider smoking cessation medications like Chantix
Withdrawal symptoms peak within the first 1-3 days and subside within a few weeks. Cravings may persist for months. But the health benefits start accruing immediately – blood pressure and pulse normalize within 20 minutes of quitting. The risk for heart disease is cut in half within 1 year. So smokers who manage to quit can rapidly reduce their risk for smoking-related diseases.
Conclusion
While smoking provides a temporary nicotine high, the long-term consequences are devastating and eventually fatal. The harmful toxins in tobacco smoke damage nearly every organ in the body and lead to numerous cancers and chronic diseases. Smokers become dependent on cigarettes to function throughout the day as nicotine addiction sets in. Quitting smoking is extremely difficult but necessary to avoid the long-term health effects. Within days to weeks of quitting, vital signs improve and the risk of heart disease and stroke starts decreasing. So while smokers may “run on” nicotine in the short term, quitting cigarettes is critical to extend and improve their lives in the long run.