How Smoking Predicts Life Expectancy

Smoking has a significant impact on life expectancy. Smoking can reduce life expectancy by as much as 10 years and sadly, Smoking is responsible for approximately one in every five deaths in the United States. There is no safe level of smoking. Each cigarette increases ones risk of dying at a younger age. Namely, people who smoke heavily (20 cigarette per day or more) are 2 times more likely to die from cardiovascular diseases1, 7 times more likely to die from cancer2, 12 times more likely to die from Chronic lower respiratory diseases3, 4 times more likely to die from influenza and pneumonia4 and 2 times more likely to die from septicemia5. Across all-cause mortality, smoking is associated with a reduction in life expectancy of up to 10 years (

Why Do People Smoke?

Because of Nicotine. Tobacco smoke is filled with nicotine. Nicotine results in the release of a variety of neurotransmitters in the brain, most importantly, dopamine and serotonin. Dopamine is a neurotransmitter that is involved in many important functions, including reward, motivation and pleasure. Dopamine holds a central role in the brain’s reward pathway 6 Surges of dopamine like the ones occasioned by nicotine consumption, lead to feelings of pleasure and reward, which are reinforcing and lead to addiction. Nicotine also leads to a surge of Serotonin, a neurotransmitter that is involved in many important functions in the body, including mood regulation, appetite and sleep. It is often referred to as the “feel-good” neurotransmitter because of its role in regulating mood and emotions. The release of serotonin in response to nicotinght05$

e contributes to the pleasurable effects of smoking, such as feelings of relaxation or euphoria. While nicotine may initially lead to a surge of serotonin, chronic nicotine use also lead to habituation, changes in serotonin functions which underlie addiction.

How Smoking Affect Life Expectancy

Tobacco smoke contains numerous toxic substances that damages nearly every organ in the body, including:

  • Lungs: Tobacco smoke can cause inflammation and damage to the airways and lung tissue, leading to chronic bronchitis, emphysema and lung cancer. But not just lung cancer. The carcinogens contained in tobacco get access to all the other organs once they have entered systemic circulation through the lungs. They get to the brain, the heart, the liver, the bladder, the kidney, the gut, the skin, everywhere. Just everywhere. And they wreak havoc everywhere. Just everywhere.  
  • Cardiovascular system: Tobacco smoke damages blood vessels. Specifically, The chemicals contained in tobacco smoke damage the lining of blood vessels, making it easier for plaque to build up and narrow the arteries. Nicotine also increases blood pressure and heart rate, which can put additional strain on the cardiovascular system over time. Blood vessel damages and increased blood pressure represents a deadly combo that increases the risk of heart attack, stroke and peripheral vascular disease. It also increase the risk of dying from those causes at an earlier date.
  • Oral and digestive system: Smoking decreases blood flow to the digestive system, which can lead to digestive problems such as stomach ulcers and inflammation of the pancreas. Smoking has namely been linked to an increased risk of developing inflammatory bowel disease, including Crohn’s disease and ulcerative colitis. Smoking also reduces the absorption of important nutrients such as calcium, magnesium and vitamins C and D. For these reasons, smoking causes oral cancer, gum disease and tooth loss, as well as increase the risk of cancers of the esophagus, stomach and pancreas. 
  • Reproductive system: Smoking reduces fertility in both men and women, as well as increase the risk of pregnancy complications and birth defects.
  • Immune system: Smoking weakens the immune system, making it harder for the body to fight infections and heal from injuries. 

Closing Remarks

Quitting smoking has immediate and long-term health benefits. Even people who have smoked for many years can improve their health by quitting smoking. In fact, people who quit smoking by age 40 can reduce their risk of dying from smoking-related diseases by about 90%.

Predicting life expectancy is complex and needs to take many factors into consideration. Youlldie allows to visualize how smoking interacts with other factors like gender, race, world region, income, education, alcohol, physical activity, sleep, blood pressure, body mass index and family history to statistically predict life expectancy.


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  3. Health Effects of Cigarette Smoking:
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