Quitting smoking in later life is tied to a 16% lower risk of dementia, but only if you don't pack on the pounds, according to a new analysis of US health data.
Researchers from Zhejiang University followed more than 32,000 dementia-free retirees for 25 years. Those who quit smoking and gained less than 5 kg saw the brain benefits. Those who gained more than 10 kg saw no significant dementia risk reduction.
Participants who never smoked had a 25% lower dementia risk compared to current smokers. Cognitive decline was 20% slower in quitters who kept weight stable.
Study author Hui Chen says the findings suggest weight management is key after quitting. Obesity and diabetes are already known dementia risk factors. The research is published in Neurology.