Daijiworld Media Network – London

London, Oct 14: Stopping smoking in middle age can slow cognitive decline so effectively that within 10 years, former smokers may have the same risk of developing dementia as people who have never smoked, according to a new study.

Researchers from University College London analysed data from 9,436 adults aged 40 and above across England, the US, and 10 European countries. They found that quitting smoking halved the rate of decline in verbal fluency and reduced memory loss by 20% over six years.

“Our study suggests that quitting smoking may help maintain better cognitive health over the long term, even when people are in their 50s or older,” said Dr. Mikaela Bloomberg, lead researcher. She added that cognitive benefits, like improvements in physical health, can occur even when smoking cessation happens later in life.

The team compared cognitive function between adults who quit smoking and those who continued. While both groups performed similarly at the start, quitters showed significantly slower cognitive decline over time. The results, published in The Lancet Healthy Longevity, underscore the importance of smoking cessation for long-term brain health.

Although the study does not prove a direct cause-and-effect relationship, the findings could motivate older smokers—who are generally less likely to quit—to give up the habit. Smoking is one of 14 identified risk factors for dementia, along with depression, excessive alcohol consumption, hearing loss, and high cholesterol. Addressing these factors is increasingly recognised as a way to reduce dementia risk.

Dr. Richard Oakley, Alzheimer’s Society associate director of research, said, “Quitting smoking, staying physically active, eating a healthy diet, and drinking less alcohol can all help reduce the risk of dementia.” Smoking is thought to harm cognitive health by affecting cardiovascular function, causing chronic inflammation, and directly damaging brain cells through oxidative stress.

Dr. Julia Dudley of Alzheimer’s Research UK cautioned that greater cognitive decline in smokers does not guarantee dementia, noting that factors like socioeconomic status or alcohol intake could influence results. Caroline Cerny, deputy CEO of Action on Smoking and Health (ASH), emphasized the importance of quitting, particularly in middle age, to prevent early cognitive decline and highlighted the need for sustained investment in stop-smoking services.

Last month, 35% of smokers in England attempted to quit, with 29% succeeding—nearly double the success rate recorded when national data collection began in 2007.