Depiction of the lungs with molecules surrounding them

The immune system is your body’s primary line of defense against disease and infection. People who smoke cigarettes are at risk for several smoking-related health problems (including earlier deaths than non-smokers)1 , and this includes harming the immune system.2

How Smoking Affects the Immune System

Here are some of the ways we know that smoking affects the immune system:

  • Many of the chemical compounds found in cigarette smoke can interfere with the immune system, causing it to work less effectively in the body’s fight against disease and infection and giving both the opportunity to progress further than it may have in a body with a healthy immune system.3
  • Smoking can change the balance, or equilibrium, of the immune system, making smokers more susceptible to autoimmune conditions.4
  • Smoking can reduce the levels of antioxidants in the bloodstream, including vitamin C levels.5 Vitamin C is highly important for not only immune system function, but for supporting infection resistance and protecting the lungs as well.6

Smoking, the Immune System & COVID-19

Since it’s so clear that there is a link between smoking and the effectiveness of the immune system, it should come as no surprise that people who smoke are more likely to be vulnerable to the novel coronavirus COVID-19.7 There are several reasons for this:

  • Smokers may already have lung disease, which could put them at higher risk for contracting COVID-19 but could also make the illness a high-risk case that may lead to fatality.8
  • Smokers may already have reduced lung capacity, which means that they may be at higher risk of contracting the virus and of suffering through a more life-threatening case.9
  • Smokers are immunocompromised, which makes them part of the population that needs to take extra precaution around COVID-19.10

How Quitting Smoking Helps the Immune System

The good news is that quitting helps. Once the immune system is no longer exposed to tar, nicotine, and all of the other chemicals in cigarettes, the immune system will start to rebound.11 It always goes without saying, but the sooner you start your journey to quitting cigarettes, the better. Explore Nicorette products, the support hub and more.

  1. Smoking and Overall Health. CDC. Date accessed April 23, 2020.
  2. IBID
  3. IBID
  4. IBID
  5. Smoking – effects on your body. BetterHealth Channel. on-your-body. Date accessed April 23, 2020.
  6. Smoking and Vitamin C: Clarifying the concerns. Nutrition Information Centre. Date accessed April 23, 2020.
  7. A on smoking and COVID-19. World Health Organization. covid-19. Date accessed April 23, 2020.
  8. IBID
  9. IBID
  10. Groups at Higher Risk for Severe Illness. CDC. Date accessed April 23, 2020.
  11. Benefits of Quitting. you-should-quit/benefits-of-quitting. Date accessed April 24, 2020.

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