Key points from article :
A large international study led by Mikaela Bloomberg, PhD, from University College London and published in The Lancet Healthy Longevity shows that quitting smoking even in midlife or older age can significantly slow cognitive decline. While mild forgetfulness is expected with aging, rapid deterioration in memory or thinking is not normal and is often linked to conditions like Alzheimer’s disease, dementia, or stroke. Because smoking damages blood vessels and increases inflammation — both of which affect the brain — researchers wanted to understand whether stopping later in life still offers protection.
The team analysed 18 years of data from nearly 10,000 adults aged 40–89 across the UK, US, and Europe. Those who quit smoking were compared with similar individuals who continued. People who stopped smoking experienced much slower declines in thinking ability: memory decline dropped by about 20%, and verbal fluency — the ability to quickly find words — declined 50% more slowly than in those who kept smoking.
These findings suggest that it is never too late to benefit from quitting. Older adults, who often face the highest risks from smoking but are the least likely to stop, may gain significant cognitive protection. Researchers now want to uncover the biological pathways behind this effect and explore whether quitting might also influence dementia-related outcomes, although normal age-related decline and diseases like Alzheimer’s follow distinct processes.
Clinicians not involved in the study say the results add another compelling reason to quit, especially for people already worried about memory changes. While the study was observational and can’t prove cause and effect, it strengthens evidence that stopping smoking — at any age — is good for both body and brain.
