Vaping may improve respiration among smokers with asthma

Smokers with past history of asthma who switched to vaping have found significant improvement and fewer respiratory infections, according to a study led by Queen Mary University of London (QMUL). The study (, published in the Journal of Addiction Research & Therapy provided sufficient information to suggest that vaping does not increase infection rates and may in fact lead to a decrease in infections. For the study, data was collected through online survey of 941 respondents who switched to vaping for at least two months and assessed subjective changes in the respiratory symptoms. The results showed that 66 per cent of respondents reported an improvement in respiratory symptoms, 29 per cent reported no change in condition and five per cent reported worsening.

“There is no doubt that e-cigarettes are much safer than conventional cigarettes, but smokers are still led to believe that they are dangerous. This misinformation includes a misreported study on rats that claimed that vaping may increase vulnerability to infections,” said Peter Hajek, Senior Author and Professor at the Queen Mary University of London. He further added “The study needs to be interpreted with caution because it is based on self-reported data, and further studies using objective measures are needed. However, the present results provide sufficient information to suggest that vaping does not increase infection rates and may in fact lead to a decrease in infections.”

Some previous cell and animal studies have been interpreted as suggesting that vaping may increase vulnerability to infection, but these studies did not use realistic exposure levels.

Human trials have reported no significant adverse respiratory effects associated with e-cigarette use for up to 1.5 years.

The researchers said that it is not surprising that the survey respondents noticed improvements in their respiratory health. This is because smoking increases susceptibility to respiratory infections and stopping smoking can be expected to have a positive effect.

In addition to this, vaping may also provide some antimicrobial protection through the e-liquid ingredient propylene glycol, though further evidence is needed to confirm this.

More information

  • Research paper: ‘Changes in the Frequency of Airway Infections in Smokers who Switched to Vaping: Results of an Online Survey’. Joanna Astrid Miler, Bernhard-Michael Mayer and Peter Hajek. Journal of Addiction Research & Therapy 2016. DOI: 10.4172/2155-6105.1000290
  • Wolfson Institute of Preventive Medicine