A group of British doctors has discovered that quitting smoking slows down age-related cognitive decline. According to the researchers, giving up this harmful habit may increase the chances of avoiding dementia.

The Positive Impact of Quitting Smoking

Quitting smoking has a beneficial effect on health and quality of life, even if a person stops smoking later in life. Previous studies by South Korean researchers also concluded that the risk of developing cancer in former smokers decreases regardless of the age at which they quit. However, the most pronounced effect was observed in those who gave up smoking before the age of 50.

New Research on the Benefits of Quitting Tobacco

The journal The Lancet Healthy Longevity has published new data on the benefits of quitting smoking, even in old age. Doctors from University College London found that people who stopped smoking experienced a slower age-related decline in mental abilities. According to the scientists, this may reduce the likelihood of developing dementia in old age.

Study Design

The authors analyzed data from many years of observations involving 9,436 people aged 40 and older from various countries. Half of the participants had quit smoking, while the rest continued. The groups were comparable in terms of initial cognitive scores, age, gender, education level, and country of birth. During the study, participants completed surveys and took memory and verbal fluency tests.

In the first six years before quitting, the decline in test results with age was about the same in both groups. However, in the six years after quitting, the trajectories began to diverge.

Results

Among former smokers, age-related decline in memory and verbal fluency slowed by approximately 20% and 50%, respectively. This means cognitive functions were preserved for a longer period.

Study Limitations

Since the study was observational, it does not prove a direct cause-and-effect relationship. Nevertheless, the results are consistent with other research suggesting that quitting smoking can be considered a preventive measure against cognitive decline and dementia.

Earlier scientific literature noted that 10 or more years after quitting, former smokers have the same risk of dementia as those who never smoked. This could be a strong argument for older smokers, who are less likely than younger people to decide to quit.

Expert Opinions

“We already knew that quitting smoking, even in later life, often leads to improvements in physical health and well-being. It now appears that, from a mental health perspective, it’s never too late to stop smoking,” the article’s authors concluded.

At the same time, Julia Dudley, a specialist at the UK Alzheimer’s Research Centre, commented in The Guardian on the limitations of the new study. She noted that a greater decline in cognitive function among smokers does not necessarily mean they will develop dementia. Additionally, differences between groups in socioeconomic status or alcohol consumption could have influenced the results, she cautioned.