Academic Research on Longevity and Its Link to Smoking

Smoking results in lower life expectancy and the magnitude may surprise you. The evidence about smoking and longevity is pretty definitive: those who don't smoke tend to live significantly longer. In our calculator, you'll often see life expectancy results that differ by 10 years or more between a non-smoker and a heavy smoker.

The numbers are striking. According to data from the The Center for Disease Control and Prevention, cigarettes cause one in five deaths in the U.S., making tobacco the leading preventable cause of death in the nation. The mortality rate among smokers is three times that of nonsmokers, mainly a result of smoking-related diseases, such as cancer, respiratory diseases, and vascular diseases. Though the heightened mortality goes for both males and females, there are gender differences in the way related medical consequences manifest. The data divides the health complications into three groups, and determines to what degree smoking increases the risk of these diseases for males versus females. Research tells us that, relative to nonsmokers, males are 17 times more likely to develop bronchitis and emphysema, and females are 12 times more likely to. For smoking-related cancers, that is cancers of the trachea, lungs, and bronchus, the increased likelihood of developing these diseases is 23 times for males, and 12 times for females. Lastly, smoking males have a 4 times greater likelihood for developing coronary heart disease, and women a 5 times greater likelihood.

In the late 1900s, women had lower smoking mortality rates than men, causing some to believe that perhaps women were not as affected by the harms of tobacco. However, a study in The New England Journal of Medicine provides evidence that that claim may be false. Instead, the study suggests the historically lower mortality rates were the result of gender differences in smoking habits, with female smokers smoking far less than their male counterparts. Today, the female smoking mortality rate has caught up to that of males. In fact, female death by lung cancer, alone, increased by 500% between 1960 and 1990, according to the CDC, surpassing breast cancer as the number one cancer death for women in the U.S.

The good news is, says Dr. Jules Mesnier in a European Society of Cardiology Press Release (2024), is that “it is never too soon or too late to stop smoking.” As mentioned above, the life expectancy of a smoker versus a nonsmoker can differ by about 10 years. The study showed that male smokers who make it to 70 years old still lose about four years off their life, with projections of 88, 86 and 84 for nonsmokers, former smokers, and current smokers, respectively. However, Clarke and his colleague, Dr. Jonathan Emberson, concluded that quitting at age 60, 50, 40, or 30 years old gives patients a chance to gain back up to 3, 6, 9, or even the full 10 years back, respectively. The CDC backs this claim as well, citing that people who quit before they are 40 years old reduce their risk of death by a smoking-related disease by 90%. The caveat, says a study in The American Journal of Epidemiology, is that cutting back on smoking won't help gain back lost years, only completely quitting will.

Though knowledge about the health risks of smoking has largely increased in recent years, smoking habits have not yet caught up to the extent needed. The numbers don't lie: tobacco takes years off your life, and chips away at your health, as well as that of those around you, and your appearance along the way.