Research has long established a connection between smoking and lung disorders. Adding a deeper understanding to this link, a recent study investigated how starting the habit before 18 affects respiratory health in early adulthood.

Young adults who began smoking as teenagers are more likely to experience symptoms like wheezing and phlegm in their 20's according to the results of the study presented at the European Respiratory Society (ERS) Congress in Vienna, Austria. The more cigarettes they smoked overall, the greater their risk of developing these respiratory issues.

The findings were based on evaluating 3430 children in northern Sweden who were asked to fill in questionnaires annually from the age of eight until they turned 19 and again when they reached the age of 28.

The researchers noted that 22% of participants were daily smokers at some point during the study. Of those who smoked, 29% started at or before the age of 15, 35% began when they were 16 or 17, and 35% started at 18 or older.

After accounting for factors such as family history of asthma and exposure to smokers during childhood, the study found that smoking more cigarettes increased the risk of respiratory symptoms by the age of 28. Each increase in "packyear" was associated with about a 10% higher risk compared to non-smokers. A packyear is equivalent to smoking one pack of 20 cigarettes per day for one year.

"Starting smoking under the age of 18 increased the risk of respiratory symptoms by the age of 28 by around 80% compared to non-smokers. In people who took up smoking at 18 or later, the risk was around 50% higher than non-smokers," the news release stated.

"In our study, we found that smokers are very likely to have taken up the habit before they turned 18, and those who did start early were more likely to be suffering from breathing problems, especially wheezing and phlegm. These symptoms were also more common the more cigarettes people smoked," said Dr Linnea Hedman, associate professor of epidemiology and public health at Umeå University, Sweden.

Dr. Hedman explains that it may be because the young population who start smoking early may continue the habit for a longer time and therefore experience more symptoms. It could also be because their lungs are still developing and more vulnerable to damage.

The findings of the study highlight how quickly the harmful effects of smoking impact young people's lives, emphasizing the urgent need to curb the habit.

"This study shows that it does not necessarily take decades to develop respiratory symptoms from smoking; we can already see a significant association in young adulthood," Dr Hedman said.

Read more