How Do Cigarettes Affect The Body?

How Do Cigarettes Affect The Body? Graphic © healthpowerboost.com. Images © Shutterstock 268321457 (under license); Pixabay 5648861 (PD)

According to the World Health Organization, tobacco is responsible for killing more than 8 million people each year. 7 million out of those 8 million are direct smokers while a shocking 1.2 million are non-smokers who are killed by second-hand smoke. ^[1] It’s a no-brainer that smoking is bad for your health and for the people around you. But what is it about smoking that makes it so dangerous?

1. Carcinogenic And Toxic Compounds

In a very popular TED-Ed video, Krishna Sudhir mentions that cigarettes contain more than 5000 chemical compounds. However, some researchers have actually estimated this number to be closer to 7000! ^[2] Out of these thousands of chemical compounds found in cigarette smoke, the FDA has listed 93 as harmful and potentially harmful constituents (HPHCs), meaning 93 are considered are carinogenic, addictive, and / or toxic to the respiratory, cardiovascular, and reproductive systems. ^[3] In fact, research published in 2011 by Talhout, et. al. brings this number of up to 98 chemicals in smoke that are likely to cause cancer, heart disease, and lung disease. ^[4]

2. Tar: Teeth Stains, Cancer and Lung Disease

As cigarette smoke enters your body, tar (the residue from cigarettes) begins to coat your teeth with black-brown sticky residue and turns them (and your fingers!) yellow. Various studies have all zeroed in on the dangers of tar exposure and they all conclude the same thing – the higher the tar content of the cigarette, the higher the risk for lung disease and cancer. ^[5] Shimatani, et. al. concluded that even low-tar cigarettes, which are gaining popularity as the “better” option, still increase your cancer risk compared to not smoking at all. ^[6]

3. Emphysema, Lung Infections, Bronchitis

Smoke in particular is very damaging to your lungs. It affects the airways, increasing your risk for lung infections like bronchitis and chronic diseases like emphysema (which is a kind of chronic obstructive pulmonary disease or COPD). In 2020, Strzelak, et. al. concluded that exposure to tobacco smoke triggers inflammation and damage to lung tissue, which contributes to the development of allergies, asthma, and chronic obstructive lung disease. ^[7]

Hou, et. al. discussed the way smoke damages the lungs through long-term exposure which leads to prolonged lung tissue inflammation. The inhaled smoke destroys the lung tissue matrix, which includes the cilia and alveoli. Cilia in the lungs are hair like fibers that help clear out mucus while alveoli are where gas exchange occurs. The damage to these tissues leads to chronic lung disease and eventually lung cancer. ^[8] This is why smokers experience shortness of breath, because the area of the lungs where gas exchange occurs (oxygen and carbon dioxide exchange) is irreversibly damaged.

4. Addiction

So why is cigarette smoking so addicting? We can blame this on the nicotine content. When nicotine hits your bloodstream, it causes the release of dopamine from the brain. Dopamine is often called the “happy hormone” because it gives us a temporary “high” when released by the brain. But this effect is only short lived, followed by a dip – which contributes to cigarettes’ addictive quality. ^[9]

A recent study on nicotine showed that the temporary high you experience when smoking eventually diminishes with chronic exposure, causing the opposite: anxiety and anxiety-driven behavior. ^[10] Smoking has also been linked to various mental health disorders, like schizophrenia, bipolar disorder, depression, and ADHD (attention-deficit hyperactivity disorder). ^[11]

Nicotine is also responsible for vasoconstriction, or the narrowing of our blood vessels. This causes raised blood pressure or hypertension and damages the lining of your arteries and veins, which leads to plaque formation. As the plaque grows larger, it eventually blocks the blood vessel and can cause a stroke or a heart attack. ^[12] Delayed wound healing can also be attributed to nicotine, with reduced blood flow to the skin because of vasoconstriction causing delayed tissue repair. ^[13]

5. It’s Not Just Lung Cancer; Other Cancers Too!

Cigarette smoking is not just a risk factor to lung cancer, it can also cause cancers in different parts of the body as well. Studies have shown how smoking is a risk factor for colorectal, gastric, and pancreatic cancer to name a few. ^[14][15][16] The chemicals found in cigarette smoke can trigger cancer development anywhere in the body, not just the lungs.

6. Compromised Immune System

Cigarettes alter the immune response in the lungs; however this effect is not confined to the lungs and the entire immune system is negatively affected. Qui, et. al in 2017 discussed the effect of smoking on immunity: It damages the way our immune cells respond to infection and disease, impacting both our innate and adaptive immunity. ^[17]

7. Infertility

A journal on endocrinology published a study in 2013 that highlighted smoking as one of the risk factors of infertility. Men and women are affected by this, with smoking causing decreased sperm motility in men and decreased ovarian reserves in women. Smoking can also damage uterine and ovarian tube tissue in women, which can also affect fertility and the viability of a pregnancy. ^[18]

While there may be studies that focus on the protective effects of nicotine and smoking on certain cancers (e.g. thyroid and estrogen-driven cancers), the risks definitely outweigh the benefits. The temporary high is not worth any of the risk – and the statistics prove it.