Smoking sparks world’s leading cause of cancer deaths

Lung cancer is the world’s deadliest cancer and cigarette smoking is its main trigger. 

Scientists have long been puzzled by a surprising fact: most smokers never develop lung cancer. Toxic chemicals in tobacco, including polycyclic aromatic hydrocarbons (PAHs), damage DNA and trigger mutations that can lead to tumor development, Caliber.Az reports, citing The Brighter Side.

These substances are among the most extensively studied carcinogens, making the link between smoking and lung cancer well established.

Recent research suggests some individuals may possess natural protective mechanisms that reduce or slow DNA damage. “Some smokers appear to possess protective mechanisms,” researchers say, opening new possibilities for cancer prevention and early detection.

By using advanced single-cell whole-genome sequencing (WGS), scientists can now precisely analyze mutations in lung cells from both smokers and non-smokers. A recent study involving 33 participants revealed that lung cells accumulate mutations with age, but smokers show a significantly higher mutation rate. Interestingly, mutation accumulation plateaus after about 23 pack-years of smoking, suggesting a biological limit potentially linked to enhanced DNA repair or detoxification in some individuals.

Simon Spivack, M.D., co-senior author of the study, explained, “The individuals who smoked the most didn’t have the highest mutation burden. This indicates that their systems may effectively counteract further DNA damage.” These findings could lead to targeted interventions for those most at risk.

Experts emphasize that quitting smoking remains the best way to reduce lung cancer risk. Yet, understanding genetic resilience may help identify vulnerable individuals early, improving prevention and treatment. As genomic technologies advance, this research lays the foundation for personalized cancer prevention strategies.

Beyond cancer, smoking harms nearly every organ. According to the Cleveland Clinic, tobacco smoke introduces over 5,000 chemicals—many carcinogenic—into the body, shortening lifespans and causing chronic illnesses like heart disease, erectile dysfunction, diabetes, respiratory conditions, and more. 

By Naila Huseynova