From the Guidelines
Starting smoking at 40 rather than 20 does reduce some health risks, but smoking at any age is harmful and the best health outcome is achieved by not smoking at all. While beginning later in life means fewer total years of exposure to tobacco's harmful chemicals, which can reduce the cumulative damage to your lungs, heart, and blood vessels, the fundamental health risks remain significant. Research shows that people who start smoking later may have somewhat lower risks of lung cancer and cardiovascular disease compared to those who begin in their teens or early twenties, simply because of the shorter duration of smoking 1. However, the body begins to experience negative effects immediately upon smoking, including inflammation, oxidative stress, and DNA damage that can lead to cancer and other diseases. Even short-term smoking increases risks of respiratory infections, reduced lung function, and cardiovascular problems. Some studies have shown that quitting smoking provides substantial health benefits at any age, with many risks beginning to decrease within days or weeks of cessation 1. Key points to consider include:
- The likelihood of developing lung cancer decreases among those who quit smoking compared with those who continue to smoke 1
- The benefits derived from smoking cessation also depend on the duration of smoking; for a given period of abstinence, the decrease in risk increases as the duration of smoking decreases 1
- Tobacco dependence treatments can help individuals quit smoking and reduce their risk of lung cancer and other diseases 1. Overall, the health risks associated with smoking are significant, and the best health outcome is achieved by not smoking at all.
From the Research
Health Outcomes of Tobacco Use
The difference in health outcomes between initiating tobacco use at age 40 versus age 20 can be understood by examining the cumulative effects of tobacco use on the body.
- Tobacco use is a leading cause of preventable death worldwide, with respiratory diseases, including chronic obstructive pulmonary disease (COPD) and lung cancer, accounting for a large proportion of tobacco-related deaths 2.
- The disease consequences of smoking occur disproportionately among the elderly due to the long duration of cumulative injury or change that underlies the bulk of tobacco-caused disease 3.
- Excess absolute rates of disease incidence and mortality due to smoking increase steadily with increasing age and duration of smoking 3.
Benefits of Cessation
- Smoking cessation benefits almost all smokers, irrespective of the age at which they quit, making smoking cessation a core component of prevention and treatment of respiratory diseases 2.
- The benefits of cessation are proportionately somewhat less among the elderly and may manifest more slowly than among younger smokers, but cessation remains the most effective way of altering smoking-induced disease risks at all ages, including those over the age of 60 years 3.
- Although the greatest benefit accrues from ceasing smoking when young, even quitting in middle age avoids much of the excess healthcare risk associated with smoking 4.
Comparison of Health Outcomes
- Initiating tobacco use at age 20 versus age 40 can lead to different health outcomes due to the cumulative effects of tobacco use on the body.
- Those who start smoking at a younger age are more likely to experience severe health consequences, including respiratory diseases and lung cancer, due to the longer duration of exposure to tobacco smoke.
- In contrast, those who start smoking at an older age may experience fewer health consequences, but still face an increased risk of smoking-related diseases and mortality 3, 4.