A new University of Chicago study is turning up the volume on a sobering message for local smokers: lighting up is linked to a higher risk of dementia, and scientists are tracing fresh lung-to-brain pathways that could help explain why. The research adds to a growing body of work that ties smoking not only to heart and lung damage but also to faster brain shrinkage and cognitive decline. For people in Chicago who are still smoking in midlife, the findings raise the stakes for both personal health decisions and local public health campaigns.
As reported by CBS News Chicago, University of Chicago investigators described new connections between the lungs and the brain and reported that smokers have higher odds of developing dementia. The brief Health Watch segment tailored the message to a Chicago audience, spelling out why this lab science matters for people living and working around the city.
A University of Chicago news release on EurekAlert walks through the molecular work behind those headlines. Researchers measured DNA methylation and gene expression changes across several human tissues and identified thousands of smoking-associated epigenetic marks in the lungs and beyond. According to the release, those molecular fingerprints suggest that the harm from cigarette smoke can spread outside the respiratory system and may involve pathways that matter for brain health.
How Smoking May Be Chipping Away At The Brain
Brain imaging studies back up the molecular story with hard structural evidence. A 2025 paper in npj Dementia analyzed MRI scans from more than 10,000 people and found that current smokers had lower normalized gray and white matter volumes, along with shrinkage in Alzheimer’s-related regions such as the hippocampus and precuneus. The authors also reported that higher "pack-years" of smoking, a measure that combines intensity and duration, predicted greater regional atrophy even after they adjusted for age, sex, and study site.
Public health organizations already treat smoking as a dementia risk factor that people can do something about. The Alzheimer's Association lists tobacco use among preventable risks for cognitive decline, and a pooled analysis summarized by Harvard Health noted that people who quit in midlife may, within roughly a decade, bring their dementia risk down to levels similar to those of people who never smoked.
For Chicagoans ready to quit, there is help close to home. University of Chicago researchers run the COMPASS smoking cessation projects and affiliated clinics that provide counseling and access to trials of medications that can support quitting. Federal guidance recommends pairing counseling with medication for the best odds of success, and the CDC lists free quitline numbers and digital tools, including the national 1-800-QUIT-NOW portal.
Scientists stress that no single study can prove cause and effect, yet the combination of molecular, imaging, and population data is building a consistent case that smoking speeds up brain aging. The practical takeaway for Chicago smokers is straightforward, even if it is not easy to act on: quitting tobacco is likely to protect not just the lungs and the heart, but the brain as well.
