Smoking tobacco and vaping electronic cigarettes may increase the risk of developing severe COVID illness among healthy young people, a new study has revealed.

According to a study published in the Journal of Molecular Medicine, smoking as well as vaping, may predispose people to increased inflammation and the development of severe COVID-19, as well as the lingering cardiovascular complications that can occur after a virus infection.

"The key message is that smoking is the worst, but vaping is not innocent," said Dr. Theodoros Kelesidis, the study's lead author and Associate Professor of medicine at the US-based University of California.

"This has been shown for many lung diseases but not for COVID. It was quite an interesting and novel finding that vaping changed the levels of key proteins that the virus uses to replicate," he added.

Using plasma collected prior to the pandemic from 45 non-smokers, 30 electronic cigarette vapers and 29 tobacco smokers, the researchers measured the levels of proteins needed to replicate the virus SARS-CoV-2, which was at the centre of the pandemic.

These proteins are ACE2, furin, Ang II, Ang 1-7, IL-6R, sCD163, and L-selectin. The three latter proteins are collectively regulated in cells by a protein known as ADAM17, the study mentioned.

Researchers found that plasma from healthy young people who smoke tobacco or vape had higher levels of furin, sCD163, and L-selectin than plasma from non-smokers.

The data suggests that in young smokers and vapers, furin and ADAM17 may be more active in immune cells and surface cells, such as those lining the lungs.

"E-cigarette vapers may be at higher risk than non-smokers of developing infections and inflammatory disorders of the lungs," Kelesidis said.

He further added: "Electronic cigarettes are not harmless and should be used for only the shortest time possible in smoking cessation, and not at all by non-smokers."