Smoking Daily Shrinks Brain, Study Finds.

A new study of more than 28,000 people suggests that daily cigarette smoking reduces the size of the brain's gray and white matter. The research provides strong evidence that smoking causally shrinks the brain. The scientists analyzed brain imaging data from the U.K. Biobank and found that participants who smoked on a daily basis at some point prior to having their brains imaged had brain volumes that were 0.4 cubic inches smaller, on average. Brain shrinkage has been associated with neurological diseases, such as Alzheimer’s disease, establishing a causal link between smoking and brain volume decline furthers our understanding of whether smoking directly drives these diseases through this mechanism.