Smoking Causes Cancer
Mounting epidemiological and experimental evidence shows that smoking is a direct, major cause of lung cancer and other serious diseases, despite historical attempts by prominent statisticians and industry-linked figures to cast doubt on causality. Commenters explore how modern causal inference (e.g., Judea Pearl’s work), genetics, and Mendelian randomization have settled most remaining debates, while also noting other significant carcinogens such as alcohol, radon, and ultra-processed foods. Personal anecdotes about cancer, long‑term smokers, and regulation-driven behavior change underscore how risk is probabilistic, strongly elevated by smoking, and heavily shaped by policy and environment.
Historical debate on causality & statistics
- Commenters discuss how an influential early statistician resisted claiming “smoking causes cancer,” arguing observational data couldn’t rule out reverse causation or hidden common causes (e.g., genotype, personality).
- Later causal-inference work (e.g., Bayesian networks, Mendelian randomization) is cited as showing smoking is indeed the main causal factor, though a genetic variant affecting nicotine addiction also independently alters lung-cancer risk.
- Some criticize oversimplified “correlation ≠ causation” skepticism and note that modern causal tools were partly developed to address exactly these questions.
Personal experiences, risk, and genetics
- Many share anecdotes: one parent dying young from lung or throat cancer, another smoking heavily into old age, often with severe non-cancer health decline.
- Several emphasize cancer and other harms as probabilistic: smoking increases lung-cancer risk ~5–10×, but most smokers still don’t get lung cancer, which explains conflicting anecdotes.
- Genetics and immune-system differences are repeatedly cited as major modifiers of risk.
Other carcinogens and risk factors
- Alcohol is highlighted as a Group 1 carcinogen linked to multiple cancers; some are surprised that alcohol-attributable cancer deaths seem numerically modest, others note newer genetic evidence suggests a larger true impact.
- Ultra‑processed foods, hot beverages, betel/areca, khat, chewing tobacco, and environmental toxins are mentioned as additional cancer risks.
- Radon in homes is discussed as the second leading cause of lung cancer in some regions; several describe high readings and effective mitigation.
Policy, restriction, and legalization
- Strong consensus that smoking restrictions (high taxes, public bans, plain packaging) reduce consumption; some recount relapsing in countries with lax rules.
- Debate over criminalizing versus regulating harmful drugs: regulated markets (like tobacco) are argued to reduce overdoses and adulterants, while others insist some drugs should remain illegal to limit availability.
Vaping and remaining unknowns
- Several ask whether vaping causes cancer; one study on DNA damage is cited.
- General expectation: likely harmful and carcinogenic, but probably less so than smoking; long-term risk remains unclear.