Overview

• University College London researchers report that people who stopped smoking after age 40 had substantially slower losses in verbal fluency and memory over the next six years than those who continued.
• Quitters experienced about a 50% slower decline in verbal fluency and roughly 20% less memory loss, translating to around six months less fluency decline and three to four months less memory deterioration per year of aging.
• The findings draw on pooled data from three ongoing cohort studies in Europe, the United Kingdom, and the United States with repeated assessments from roughly 2002 to 2020.
• Authors stress the analysis is observational, yet note biological plausibility through smoking-related vascular injury, chronic inflammation, and oxidative stress, and they link slower decline with lower dementia risk.
• Reports acknowledge short-term nicotine withdrawal can cause temporary cognitive symptoms, while the results offer fresh motivation for cessation efforts and policy support, especially as quit attempts drop in middle age.