Smoking has long been linked to heart disease, lung cancer, and respiratory failure, but its toll on the brain is now coming into sharper focus. A large-scale scientific review, involving roughly 2.8 million participants, has found that the more cigarettes a person smokes per day, the higher their risk of developing dementia—including Alzheimer's disease and vascular dementia. The findings, published in eClinicalMedicine, add to a growing body of evidence that tobacco use is a modifiable risk factor for cognitive decline.
The research, led by scientists at Curtin University in Australia, shows that smokers overall face a 31% higher risk of dementia compared with people who have never smoked. That figure rises to 40% for Alzheimer's disease and to 52% for vascular dementia, a condition often linked to reduced blood flow to the brain. The study's authors stress that the relationship is dose-dependent: smoking 10 cigarettes a day is associated with a 16% increased risk, while 20 cigarettes a day raises the risk by 34%.
Why this matters for Europe
Europe has some of the highest smoking rates among developed regions, particularly in countries like Greece, Bulgaria, and France, where tobacco use remains a significant public health challenge. With dementia already affecting millions of Europeans—and numbers expected to rise as populations age—these findings carry particular weight for health systems across the continent. The study's lead researcher, Mario Serfo, emphasized that the results should prompt a broader conversation about brain health. “We need to pay attention to the impact of smoking on the brain, alongside its well-known risks to the heart and lungs and the likelihood of developing cancer,” he said.
The study also offers a hopeful message: people who had quit smoking did not show a higher risk of dementia compared with never-smokers, and their risk was lower than that of current smokers. This suggests that quitting—even later in life—can substantially reduce the threat. Co-author Blossom Stephan called for brain health to be included in discussions about the risks of smoking and the benefits of giving it up. “We should be talking about cognitive function as much as we talk about lung cancer,” she said.
The researchers are urging public health authorities to expand tobacco control campaigns to include warnings about dementia. They recommend adding messages about brain health to cigarette packaging and integrating them into smoking cessation programmes. Such measures could help raise awareness among the millions of Europeans who still smoke, many of whom may not realize the neurological risks.
While the study does not prove a direct causal link between smoking and dementia, it adds to a robust body of evidence. Previous research has shown that smoking can damage blood vessels, reduce oxygen supply to the brain, and accelerate the buildup of plaques associated with Alzheimer's disease. The new review, which pooled data from dozens of studies, strengthens the case that smoking is a major preventable risk factor.
For European policymakers, the implications are clear. As the continent grapples with an ageing population and rising dementia rates, reducing smoking could be one of the most effective strategies to protect brain health. The findings also align with broader efforts to curb tobacco use, such as the EU's tobacco control directives and national campaigns in countries like Ireland and Finland, which have set ambitious smoke-free targets.
In the meantime, the message for individuals is straightforward: the fewer cigarettes, the better. And for those who have already quit, the study offers reassurance that their risk of dementia has likely fallen back to the level of someone who never smoked. As the research community continues to explore the links between lifestyle and brain health, this review serves as a timely reminder that what we smoke today shapes our cognitive future.
