If you model a generation in which the smoking prevalence rate falls to near zero — not through gradual social change, but through a legal floor that prevents uptake entirely — the downstream effects on life insurance mortality, on health insurance claims frequency, on critical illness payouts for lung cancer, heart disease, and chronic obstructive pulmonary disease, are enormous. A cohort that does not smoke at all is a cohort that, on average, lives longer, spends less time in hospital, draws less on long-term care, and generates fewer large catastrophic claims in the middle decades of life.
